02 2013 Twentyfour7. WÄRTSILÄ TECHNICAL JOURNAL ENERGY A mega size power plant project Constructing two 215 MW dual-fuel plants on the same site 4 48 25 A new service agreement solution Preventing the unexpected for peaking power plants Assessing competence A new insight into professional skills management MARINE Introducing the Wärtsilä X82 Better fuel efficiency for VLCCs 30 COVER STORY page 42 INCREASING FLEXIBILITY in LNG fuel handling
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WÄRTSILÄ TECHNICAL JOURNAL
ENERGY
A mega size power plant project Constructing two 215 MW dual-fuel plants on the same site
4
48
25 A new service agreement solution Preventing the unexpected for peaking power plants
Assessing competence A new insight into professional skills management
MARINE
Introducing the Wärtsilä X82 Better fuel efficiency for VLCCs
Emphasising flexible power generationWärtsilä’s gas fired combustion technology is capable of solving power system stability problems (see page 9).
THIS ISSUE OF IN DETAIL is also available on iPad as a Wärtsilä iPublication app from Apple's Appstore, as well as in a browsable web version at http://indetailmagazine.com/.
WE AT WÄRTSILÄ take great pride in the fact that our company is
an acknowledged innovator and technology leader, and that our
strong in-house know-how is used to constantly improve the value
proposition we offer our customers.
PRIME EXAMPLES of our pioneering technology achievements
can be seen in Wärtsilä’s Smart Power Generation concept for
land-based power plants, and the development of solutions that
have helped facilitate the use of gas as a marine fuel. In both these
areas, and more, Wärtsilä continues to lead the way to a more
economically and environmentally sustainable world.
IN THIS EDITION OF IN DETAIL magazine, further evidence of our
technology accomplishments can be found. Each of these articles
points to a path that offers a shorter and faster way to customer
profits, and it is for this that we strive day after day. For it is by
optimising the lifecycle efficiency of Wärtsilä installations around
the world, be they on land or at sea, that we build trust and
reputation and become the preferred partner of all our customers.
WE ARE UNIQUELY POSITIONED to combine this technology
leadership with our global experience, our world class service
support network, and the operational data that has been gained to
reduce and control operational costs. Our work towards implementing
an effective Ship Energy Efficiency Management Plan (SEEMP) is
just one good example of this, and you can read more about it in
this magazine. In fact, each of the articles illustrates, in one way or
another, how Wärtsilä helps its marine and power plant customers
to achieve fuel cost reductions and important efficiency gains.
I wish you good reading.
Roger Holm
Senior Vice President
4-Stroke
Contributing editor
to this issue of In Detail
iPad
Web
WÄRTSILÄ TECHNICAL JOURNAL | WWW.WARTSILA.COM
in detail 3
INCREASING FLEXIBILITY IN LNG FUEL HANDLING
The LNGPac™ ISO fuel gas handling system offers a new and flexible approach
that expands the possibilities for LNG as a marine fuel. PAGE 42
Effective implementation of SEEMP
Wärtsilä’s new offering combines SEEMP with service agreements for greater customer benefits.
Wastewater treatment in the marine industry
Wärtsilä continues to develop state-of-the-art wastewater treatment systems for ships while awaiting regulatory enforcement.
A future market design for reliable electricity systems in Europe The changed market environment requires a new approach to electricity market design.
MORE ON PAGE 54RE
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MORE ON PAGE 61MORE ON PAGE 12
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Power demand in the Caribbean island of
the Dominican Republic has been growing
at around 5 per cent per annum. At the
same time, the transmission system is weak
and overloaded. Despite its best efforts, the
government has therefore long struggled to
bring uninterrupted power to the island’s
industry and 10 million inhabitants.
To help ease the situation, the
government has allowed independent power
producers to set up projects that will help
meet this growing demand. Meanwhile,
some industries have taken control of the
situation by opting to install their own
power plants in order to secure supply.
Against this background, Wärtsilä is close
to completing one of it’s largest installations
at a site in San Pedro De Macoris, 70 km
east of the capital Santo Domingo.
Under two separate engineering,
procurement, and construction (EPC)
contracts, Wärtsilä is supplying and
installing two almost identical power plants,
known as Quisqueya I and II, with a total
capacity of 430 MW for two separate clients.
The first project is a captive power plant that
will power the Pueblo Viejo gold mine
operated by Barrick Gold, while the second
will be an important generating asset for
local independent power producer EGE Haina.
Constructing a mega size multi-fuel power plantAUTHOR: Seppo Tiensuu, S enior project manager, Power Plants
Wärtsilä is close to completing two 215 MW combined cycle power plants on a single site in the Dominican Republic. Although a huge undertaking, projects of this size are fast becoming “business as usual” for the company.
Fig. 1 – Aerial view of the Quisqueya site in March 2012 when site works had been started.
WÄRTSILÄ TECHNICAL JOURNAL 02.2013
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Power from this plant will be sold to the
national grid.
Neither company is a stranger to Wärtsilä,
as both have purchased Wärtsilä plants in
the past. This time, each plant will consist
of twelve Wärtsilä 50DF engines and a steam
turbine in combined cycle configuration.
Almost identical
Quisqueya I is located some 100 km from
where its output will be consumed at
the Pueblo Viejo gold mine, northwest of
Santo Domingo.
Barrick Gold holds a 60 per cent interest
in the mine and is the operator, with
Goldcorp owning the remaining interest.
The mine achieved commercial production
in January 2013 and is expected to ramp up
to full capacity in the second half of the year.
Having invested some USD 5 billion
in the gold mine, being self-sufficient in
power supply is a smart move for Barrick
Gold – both practically and economically.
Currently, Barrick Gold is buying
electricity from the grid, but by building
this new plant it will both ensure an
adequate supply and achieve considerable
cost savings.
The fact that these two projects are almost
identical and located next to each other is
no coincidence, despite the fact that they
have different owners and functions. EGE
Haina had an existing relationship with
Barrick Gold, and initial discussions between
Wärtsilä and Barrick ultimately led to the
same configuration being selected for
the EGE Haina plant. EGE Haina will also
operate the Quisqueya I plant on behalf of
Barrick Gold.
Flexibility is key
EGE Haina is an important operator in the
country and its new power plant will play a
key role in the island’s network. Considering
the size of the total Dominican grid,
the project’s size is significant – big enough
to provide frequency support.
Operational and fuel flexibility were big
considerations in the selection of Wärtsilä
technology for the project. In addition to
offering frequency control with its fast start-
up, the plant offers high electrical efficiency
and can run on gas and liquid fuel.
Fig. 3 – The Quisqueya site management crew.
Santo Domingo
Caribbean Sea
DOMINICAN REPUBLIC
Atlantic Ocean
San Pedro De Macoris
Fig. 2 – Quisqueya I and II are located in San Pedro De Macoris, 70 km east of the capital Santo Domingo.
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Introduced in 2007, the new Wärtsilä
50DF with its multi-fuel capability is the first
large engine to offer such flexibility.
The Wärtsilä 50DF allows for fuels to be
switched whilst the engine is in operation.
This is a huge benefit in terms of giving
plant owners options as fuel prices fluctuate.
Initially, Quisqueya I and II will burn
HFO until natural gas is available. Although
some gas is available on the island, currently
there is not enough gas for a facility of
this size. There is an import terminal but
no pipeline. An installation of this size
requires a separate import terminal and
its own pipeline from the port to the site.
As this could require an investment in the
region of USD 1 billion, it may be some
time before the projects run on gas.
In addition to fuel flexibility, a big plus
compared to gas turbine plants is that
overall plant efficiency can be maintained
across a much wider load range by simply
shutting down engines according to power
needs. Since the engine’s introduction, it
has been selected for several projects ahead
of gas turbine-based solutions, and the
Quisqueya plants further verify Wärtsilä’s
strategy for the large power plant sector.
Plant configuration
Apart from some minor differences on
the fuel treatment systems, the scope of
supply for both plants is almost the same.
In addition to the power generated by
the Wärtsilä 50DF engines, waste heat will
be recovered in a heat recovery steam
generator (HRSG) to generate steam that
is used to drive a single pressure steam
turbine for additional electricity.
Wärtsilä’s scope of supply covers the
engines, auxiliaries and combined cycle
equipment. The steam turbines were sourced
from Shin Nippon Machinery (SNM) Co.
Ltd, of Japan, while the boilers were
sourced from Aalborg Boilers. Wärtsilä has
responsibility for installing the steam
turbines and boilers as well as the engines
and auxiliaries.
Each Wärtsilä 50DF engine has a power
output of 17 MW, while the contractual
output of each steam turbine is 16.5 MW,
i.e. almost 10 per cent of plant output.
The steam turbine, however, is designed
so that it is capable of producing 20 MW
if more steam is available. Steam is fed
into the steam turbine at a pressure of
15 bar and a temperature of 335°C.
Cooling is provided by means of
radiators for the engines, and a cooling
tower for the steam turbine.
For each plant, there are two engine halls
each housing six engines. The steam turbines
are located in a separate building and the
HRSGs are located outdoors. Office buildings
are located in a row on one side of the plant
and the tank yard is on another side.
Each project has two fuel storage tanks,
each with a capacity of 14,300 m3. This is
sufficient storage to allow each plant to run
at full load for around 700-800 hours.
Adapting the schedule
The site for the two plants occupies an area
of 480,000 m2. With such ample space,
achieving the optimum plant layout was
rather straightforward.
One of the major challenges in executing
the project, however, has been the sheer
size of the power plants and the pressure it
placed on the scheduling and contractors.
The contract for Quisqueya I was signed
in August 2011, while the contract for
Quisqueya II was signed in December.
The initial plan was that there would be a
4-month gap between the two projects, but
Fig. 4 – The Wärtsilä 50DF offers excellent operational and fuel flexibility.
WÄRTSILÄ TECHNICAL JOURNAL 02.2013
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delays caused by factors such as
environmental permitting, meant that both
plants had to be constructed on a very
similar time schedule.
Under normal circumstances, a typical
sequence would be to carry out the
engineering, followed by procurement and
shipment. Foundations are then constructed,
mechanical and electrical equipment is
installed, and then the plant is commissioned.
The shift in schedule, however, meant that
a large number of tasks had to be carried out
in parallel. For example, two or three engine
halls were worked on simultaneously during
installation works. This created a more
crowded site, which put a lot of pressure
on site supervision and the constructors.
Building such a large project on an island
the size of the Dominican Republic was also
a challenge for local contractors, but it did
have its benefits.
During the peak of construction in
the spring of this year, there were around
1400 workers on site. With the total number
of man-hours expected to reach 3.5 million
by completion of the project, the construction
has provided local jobs and boosted
the economy.
Logistical challenge
In addition to supplying and installing the
engines, Wärtsilä’s contract also covered
soil improvement and foundation work.
Although no piling was needed, soil
preparation required the excavation of as
much as 300,000 m3 of soil, which then had
to be filled with caliche, a type of sedimentary
rock that was brought in from a nearby
quarry.
As both plants are designed to withstand
category 4 hurricanes, building adequate
foundations was another major challenge.
Due to the potentially huge wind loads,
foundations and steel structures had to be
much bigger than usual. The foundations
required 18,000 m3 of concrete to be
poured, while the installation of 1700 tons
of reinforced steel, and 3000 tons of steel
superstructures were also necessary.
With site preparation and foundations
complete, the task of delivering equipment
to the site could begin.
The engines were shipped to Boca Chica
Port in Santo Domingo and then transported
by road to the site. Roads between the port
and site are relatively good, so equipment
delivery went smoothly without any hiccups.
As all materials had to be available on site
when needed, the entire project has been
a huge logistical challenge. Total shipment
volume consisted of more than 1200
containers and 33,500 m3 of various break
bulk. Getting all the equipment in the right
place at the right time required careful
planning and good coordination of transport
activities.
Responsibility for transportation was
assigned to one main contractor who was in
charge of the collection and ocean transport.
Local transport and coordination was then
subcontracted to a local company.
A storage yard was also rented at the port
so vessels could be unloaded immediately on
arrival prior to the goods being transported
to the site.
Business as usual
In spite of the challenges, construction has
proceeded extremely well thanks to
successful site management, excellent
cooperation with the clients, and flexible
subcontractors.
Despite the challenging schedule, extremely
good health and safety conditions were
maintained, with the LTI < 0,06 (loss time
Fig. 5 – View of the plants showing the four combined cycle units on the left and storage tanks on the right. One of the six-cell steam turbine cooling towers can be seen in the foreground.
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injury) rate being clearly better than
the target value.
The fact that such a large project has
progressed smoothly is evidence that
constructing these big combined cycle plants
is no longer a daunting task. Years ago,
reciprocating engine-based plants were
significantly smaller. Today, building 200+
MW power plants is in many ways now just
‘business as usual’ for Wärtsilä.
Processes have been put in place and
working methods have been established that
allow power plants of this size to be built
quickly and on schedule.
Quisqueya I and II are further evidence
of this. Site works began in February 2012
and performance tests started in September
2013. With the plants scheduled to be ready
for handover for simple cycle operation this
autumn, this means that from the start of
excavation to simple cycle operation, just 18
months will have passed. Combined cycle
handover is planned for November/
December 2014 , i.e. just 22 months from
the start of site works.
This is quite an achievement for a project
of this size, especially when considering
the shortage of resources on the island.
Clearly, Barrick Gold and EGE Haina have
overall been happy with Wärtsilä’s handling
of the projects. In spite of the demands of
the project, communication and cooperation
with both companies has been excellent.
These are old clients of Wärtsilä, which
may have been one of the reasons why
Wärtsilä was contracted for the projects, but
their smooth execution reaffirms that
Wärtsilä is a good contractor for large or
small projects and provides an excellent
foundation for future cooperation.
Fig. 6 – Impressive Quisqueya site in September 2013, just 18 months from the start of site works.
WÄRTSILÄ TECHNICAL JOURNAL 02.2013
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The share of wind and solar power in many
grids has increased rapidly during the last
few years, especially in Europe and the USA.
This trend is sometimes causing severe
problems in stabilising the power systems.
As a result, it can be foreseen that in the
future all electricity generation, with the
exception of nuclear power and power from
renewable energy sources, will need to be
run on a completely flexible basis, responding
rapidly to the prevailing needs of the grid.
Undoubtedly, the business of power production
is profoundly changing.
Wärtsilä's gas fired combustion technology
has the flexibility to enable maximum use of
fluctuating wind and solar energy, while
ensuring optimal power production with
the highest total efficiency. While other
thermal power generating systems typically
need to be started an hour or more
beforehand to reach full load, advanced
power plant solutions can reach full load
for power generation in just a few minutes.
For several years already, Wärtsilä's R&D
activities have focused heavily on developing
means to achieve superior flexibility in power
generation. As a result, the company is
currently the global leader in this technology
field. Highly competitive cost efficiency is
another major target of Wärtsilä's
development work.
The aim is to continue to improve and to
find the most cost effective solutions for
power generation. The company’s Research
& Development team, consisting of hundreds
of experts in different disciplines, is working
Emphasising flexible power generation AUTHORS: Tuula Franck, S enior Manager, Media and S takeholder Relat ions
Thomas Hägglund, Vice President , Power Plants Technology
Developing superior flexibility in power generation and highly competitive cost efficiency have long been major focus areas in Wärtsilä's technology development work.
Fig. 1 – Wärtsilä's gas fired combustion technology is capable of solving power system stability problems.
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to constantly improve the technology and
to develop Wärtsilä’s offering as a total
solutions provider. Furthermore, an important
area of research and development is the use
of new fuels. This work has resulted in
power solutions with market leading fuel
flexibility, making them extremely competitive.
When rapid up and down ramps of power
generation are necessary to stabilize the
system load, Wärtsilä's gas fired combustion
technology offers the highest total efficiency
on the market. The essence of this fast-access
efficiency is that the power generation can
be started and stopped so rapidly that one
could speak in terms of generating power
in pulses. The length of such a ”pulse”,
containing one cycle of power generation,
could typically be from half an hour to
a few hours.
The Wärtsilä system reaches full load
for power generation in just a few minutes,
while other thermal power generating
systems typically need to be started an hour
or more beforehand to reach full load.
Wärtsilä’s technology makes it possible to
achieve fast ramps up and down that take just
one minute, while providing very high total
efficiency for the cycle of power generation.
The shorter a single cycle of power
generation is, the greater the importance
of a quick starting time to reach full load
and total efficiency during the cycle. For
example, when running a 60 minute cycle, a
Wärtsilä gas power plant can operate well
at full load for more than 50 minutes.
With a net electrical efficiency of over
45 per cent at full load, the efficiency for
the whole cycle thus exceeds 44 per cent.
A short ramp up time, together with high
total efficiency, further implies that the
exhaust emissions are minimized. Emissions
from power generation are generally
measured at full load, since they vary and
are difficult to measure during the start-up
phase. With short up and down ramps you
save in fuel costs and reduce emissions.
Speed and flexibility needed in future
Coal combustion is not suitable for use as
fast regulating power, while to get the full
effect from combined cycle gas turbines
(CCGT), the system has to be started at least
one hour before power is needed. As a
consequence, when used as back-up, turbines
in these power plants are continuously
spinning and thus lose a lot in total efficiency.
Furthermore, conventional plants have to
run for many hours at a time to make power
generation profitable. In order to generate
a positive cash flow, today’s high efficiency
gas fuelled power plants need to be run for
more than a couple of hours at a time.
On the spot market electricity is
normally traded by the hour, but in fact
the fluctuations in both demand and
price are a lot faster than that - and are
accelerating. Clearly, the business of
power production has changed radically
and is becoming ever harsher. For a
power plant that is not fast enough, yet is
working as back-up to the growing load
from renewables like wind and solar, the
situation is getting more and more difficult.
It is not just a question of levelling out the
peaks and valleys in the fluctuating power
output from renewables. The real challenge
is that at any point in time the decision
must be made as to when is the right time
to start up or shut down different power
units. At the same time, one has to take
into account the fact that the power plant
is slow in starting, and once having started
it, one must be able to sell the electricity
over a period of several hours, and not to
produce it at a loss. Forecasting the daily
load pattern is no longer sufficient, since
the production of wind and solar power
needs also to be taken into consideration.
It is, therefore, predictable that in the
40,000
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20,000
15,000
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Fig. 2 – Variable wind.
Wind Power output major wind energy countries Europe,
January 2012
WÄRTSILÄ TECHNICAL JOURNAL 02.2013
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future all power generation, with the
exception of nuclear power and power
from renewables, must be run completely
flexibly, according to the prevailing grid
needs. Such a power generating system
has to be extremely fast and flexible.
Problems in stabilizing power systems predicted
International energy policies are changing,
and the European Union, for instance,
continues to persuade its member countries
to increase their share of energy production
from renewable energy sources. This trend
implies severe problems in stabilizing
these power systems.
For example, within a very short period of
time Germany has installed a large amount
of photovoltaic systems feeding solar power
into the grid. Additionally, Germany had
previously invested in extensive wind power
installations, which now produce some eight
per cent of the country's electricity. As a
result, there are indications of increasing
instability in the German grid and, as
a consequence, a need for fast regulating
power generation.
Production of electricity with wind
turbines is not stable since it fluctuates all
the time with occasional rapid changes.
Adding electricity produced with solar
panels makes the generation of electricity
even more unstable – even though the daily
and annual rhythm of solar conditions
should be easier to forecast than wind
conditions. To this should be added the fact
that the storage of enough electricity to
level out these fluctuations is very difficult,
if not impossible, to achieve.
When peaks and lows in energy
production from renewable energy sources
are local, a grid covering an extensive
geographical area can level out the largest
fluctuations. However, occasionally not
even an all-European grid is large enough to
balance the fluctuations. The study of some
historical data shows that the fluctuations
in the combined wind power output
from three leading European wind power
countries – Spain, Germany and Denmark
– are not necessarily levelled out, but are in
fact somewhat reinforced. (see Figure 2)
Fast and flexible balancing power is
needed, not only to enable more renewable
energy, but also to enable adequate use of
today's fossil fuel power plants. Without
flexibility, the benefits from renewable
energy are lost in lower efficiencies and
higher emissions from the existing plants.
There are several features that contribute towards achieving a fast start-up, and
the technical solutions are continuously being further fine-tuned. An example of
what can be accomplished is the two power stations that Wärtsilä has supplied
to Elering AS, the Estonian transmission system operator. The plants are under
construction at Kiisa, near Tallinn, and will have a combined output of 250 MW.
The Kiisa installations are intended to secure the availability of Estonia's
electricity supply in case of sudden drops, and are capable of compensating
for a system failure within 10 minutes. The 27 Wärtsilä 34DF engines
involved will operate individually on average for 200 hours per year.
Heat pumps and efficient insulation are used to keep the temperature
inside the engine hall relatively high during stand-by. In that way the loss
of heat in the engines during stand-by can be reduced and, consequently,
the need for pre-heating prior to starting can also be lessened.
Pressure air speed up the engine (starting air), and when defined speed reach
the fuel supply start and followed by ignitions. Using compressed air makes the
procedure fast, and no electricity is needed to start the system. When the engine
is warm at start, it reaches full speed in 30 seconds, after which it is individually
synchronised and connected to the grid. Adding load and ramping up the
engine to full load takes approximately two minutes with a warm engine.
Also ramping down is a fast procedure, normally taking about one minute. While
compressed air is used to get a rapid start, letting off the pressure from an engine
by opening a valve is an efficient way to instantly stop the engine, if needed.
During the ramp down, preparations are made at the same time for the next
cycle of power generation with, for instance, residual gas being vented out.
Within five minutes the engine is ready to start again and the heat remains in
the engine for quite a while. The number of starts and cycles of operation is not
relevant since the engines are not affected by how often they are started.
FULL SPEED IN 30 SECONDS WITH A WARM WÄRTSILÄ ENGINE
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Market situation in the EU
Reliable operations in electric power
systems having increasing amounts of
Renewable Energy Sources (RES) require
increasing balancing capabilities. This
is because the output from variable RES
generation is never fully predictable
(forecast errors), and has variability that
adds to the normal variations in electricity
demand. Since RES production generally
has feed-in priority, the remaining power
generation capacity has to adjust its
output in order to balance total electricity
production and demand. Electricity
demand, as well as the output from RES,
can change rapidly and not necessarily
in the same direction. System operators
therefore need to have capacity available
that can respond quickly to these changes.
The impact of RES deployment on
electricity markets is severe. Variable RES
generates electricity at very low marginal
costs and thermal capacity is, therefore,
pushed higher up in, or completely out
of, the merit order. This means reduced
operating hours and less revenue for
thermal capacity. In addition, subsidized
RES output depresses electricity prices,
which makes the feasibility of thermal
plants even more challenging. Thermal
Future market design for reliable electricity systems in EuropeAUTHORS: Matti Rautkivi, General Manager, L iasion Off ice, Power Plants
Melle Kruisdijk, Market Development Director Europe, Power Plants
De-carbonising the energy sector is one of the main objectives of the EU. To meet this objective, significant amounts of variable renewable capacity have been installed already and a lot more will be deployed by 2020. This development raises the need for more flexible generation in power systems, and a new kind of electricity market design to reward flexible generation.
This article is based on a paper that won the best paper award in Power Gen Europe 2013.
WÄRTSILÄ TECHNICAL JOURNAL 02.2013
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capacity is still needed in systems with high
levels of RES to balance the system, but the
profitability of these assets is jeopardized.
Several EU member states have raised
a concern that, as a result of plant closures
and the lack of investment in new
capacity, there may become insufficient
capacity available under current market
arrangements. There is a potential market
failure that is associated with the perceived
political risk of allowing prices to reach
high levels at peak times. Such high
prices would be required to remunerate
plants running at lower load factors, so
that they are able to recover fixed costs
whilst operating for only a small number
of hours per year. This issue has been
termed the “missing money” problem.
However, there is another issue that
must be addressed since it is not simply
“capacity” that is required in high RES
systems. Consideration must also be given
to delivering the “right types” of capacity,
and in particular, that a sufficiently flexible
mix is available. Without appropriate
price signals, there is an equally important
concern around “missing flexibility”.
The value of flexibility
If more intermittent renewable power
sources are to be implemented into
power systems, more flexible generation
capacity has to be added to the mix as
well. Though this has been recognised
among transmission system operators
(TSOs) and market players, the value
of flexibility has not been quantified or
identified in the market arrangements.
To identify and quantify the market value
of flexibility, Wärtsilä has developed
several studies around this topic with
the approach summarised in Figure 1.
The savings that flexibility in power
systems can provide has clearly been
demonstrated by two recent studies
commissioned by Wärtsilä. The first
study, carried out by Redpoint Energy and
London Imperial College concerning the
UK market, is covered in another article in
this magazine (See article "Flexible energy
allows efficient and cost effective integration
of renewables into power systems"). The
analysis demonstrated that, depending on
the wind scenario, flexible gas generation
could save UK consumers
Fig. 1 – An approach for defining the value of flexibility.
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NS Optimize
the operation of capacity mix to minimise costs and emissions
Required inputs available
Capabilities and features of technologies
Weather and load data
System requirements
Cost optimized system operations for each hour
STEP 2
PO
WE
R S
YS
TE
M A
RC
HIT
ECT
UR
E Objectives of future energy system?
CO2 reduction
Reliability
Cost
Available technologies
Capacity scenarios
Physical system layout
STEP 1
Smart Power System
Affordable
Reliable Sustainable
VA
LUE
OF
FLE
XIB
LIT
Y Results of scenarios
System operating costs
CO2 emissions
Reasons behind results
How much savings and CO2 reduction can be achieved through more flexible generation?
STEP 3
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ENERGY MARKET FLEXIBILITY MARKET CAPACITY MARKET
PurposeOptimal utilization of assets
to generate electricity
PurposeEfficient provision of flexibility
to meet system requirements
PurposeEnsure capacity adequacy
Objectives• Low cost of electricity
• Low CO2 emissions
Objectives• Reliable system in all
situations
• Low cost of system balancing
• Maximum utilization of low
cost generation assets
Objectives• Adequate capacity
• Bankability of new
investments
• Keep competitive generation
assets in the system
Market setup• Liquid short term markets
• Efficient competition
• Balancing responsibility
for all market participants
• Transparent price formation
Market setup• Transparent price for
flexibility
• Flexibility traded in short term
• Efficient competition on
electricity and flexibility
market
Market setup• Central capacity market
• Competitive auctions
• Competition on equal basis
• Efficient market entry
and exit
Investment signals• Electricity price
• Electricity demand
• Merit order
Investment signals• Need for flexibility
• Flexibility price
• Flexibility capabilities
Investment signals• Required capacity payment
to support investments
Approach to market design for high RES system
Fig. 2 – Market design for high RES power systems.
WÄRTSILÄ TECHNICAL JOURNAL 02.2013
15in detail
between GBP 380 million and GBP 550
million per year by 2020 through reduced
balancing costs. The modeled savings
are estimated to be significantly higher
in 2030 (GBP 580 million to GBP 1,540
million) since the system’s volume of wind
generation is anticipated to increase further.
In another paper, KEMA DNV analyzed
the Californian system for 2020 with
a 33 renewables penetration [http://
www.smartpowergeneration.com/spg/
downloads]. In this context two alternative
scenarios were modeled. The first
scenario covered the additional capacity
requirement of 5.5 GW with traditional
gas turbines, and the second with Smart
Power Generation (SPG). The study shows
that by introducing 5.5 GW of SPG instead
of 5.5 GW of gas turbines in the system,
Californian consumers could save around
900 MUSD per year, representing some 11
savings in system level operating costs.
Based on the studies, it is evident that by
including SPG into the generation portfolio,
total system operating costs in systems
with high penetrations of RES are reduced.
This is due to the specific characteristics of
SPG, such as ultra quick start-up, that allow
this technology to provide flexibility to
the system at much lower costs compared
to other thermal generating technologies
that have to run part-loaded. In addition,
by adding SPG to the capacity mix of a
power system, other thermal plants no
longer need to run part-loaded and can
produce electricity at higher efficiency,
which reduces the overall generating costs.
A system without SPG can provide flexibility
by running plants at part load, but such
actions significantly increase the cost to
consumers, as is shown in the studies.
The value of flexibility in the examined
60 GW (UK and California) peak load systems
having high RES penetration is analysed as
being more than EUR 500 million per year.
Translating this to a European size system,
the value of flexibility is approximated to
be more than EUR 5 billion per year, already
in 2020. Consequently, flexibility should
be one of the key parameters of future
power system and energy market designs.
Current market challenges
Lately, there has been an active debate
regarding capacity mechanisms in many
European Union member states. In
February 2013, the European Commission
asked for input from stakeholders on
potential ways to secure capacity adequacy
and system reliability in a future system
with high amounts of RES. However, such
a power system also calls for flexibility,
not just capacity. As clearly indicated in
the studies mentioned above, in high RES
power systems flexibility is no longer an
invisible and low cost side product of
power generation, but is a key factor in
power system design and optimization.
Though the studies presented earlier
clearly show the benefit of having
flexibility in the capacity mix, current
market arrangements do not reflect the
value of flexibility, nor do they incentivize
investments in flexibility. There are several
issues within current market setups
that “hide” the cost of inflexibility into
consumer bills, and consequently prevent
investments in new flexible capacity.
Simultaneously, energy-only market setups
are struggling to keep capacity adequacy
at healthy levels in this new reality.
The electricity market vision
Wärtsilä studied several electricity market
models with the aim of developing an
electricity market model that will incentivize
flexibility and ensure capacity adequacy for
systems having high levels of variable RES.
The market model should secure capacity
adequacy, incentivize the right type of
capacity, and lead to lower costs to the
consumer. The overall market model design
that will deliver this is shown in Figure 2,
and is based on two markets existing next to
each other. The Energy Market, consisting
of the wholesale electricity markets (day-
ahead, intra-day, and the balancing
market), together with a Flexibility
Market establishes a competitive market
environment where all market players can
compete on an equal basis. A competitive
Capacity Market would be introduced only
if needed, to secure capacity adequacy.
A competitive Energy Market forms the
basis of the market model. The objectives
of energy markets are to provide low cost
electricity and low CO2 emissions in all
situations through competitive short term
markets. Cost reflecting imbalance prices
will increase the imbalance exposure of all
market participants (where all participants
are responsible for balancing), which creates
the incentive to be in balance at gate closure
(when the market trading is closed and TSO
takes control of the system). Supply and
demand for energy closer to gate closure is,
therefore, expected to increase because each
market player, in order to reduce
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out-of-balance penalty risk, will take
efforts to be in a balanced position at gate
closure. This will be done either through
changed positions within its own portfolio
of options (changing outputs from their
own power plants, DSR, etc.), or through
trading. This development enhances the
liquidity in intra-day markets, and provides
additional income for flexible assets
through balancing and intra-day markets,
because these units will be in a position to
supply energy shortly before gate closure.
However, it would be hard, or even
impossible, for providers of flexibility to
capture the total value of flexibility through
energy prices only. Therefore, in addition
to the Energy Market, we propose the
introduction of a market place for flexibility.
A competitive Flexibility market would be
a day-ahead option market for having the
flexibility to increase/decrease energy the
following day. The flexibility market would
replace the existing procurement strategies
of TSOs, and would make the procurement
of system services more transparent to
market players. TSOs would procure the
required flexibility (reserves) to satisfy the
system needs for the following day from
the flexibility market, when the volumes
are not locked away under long-term
contracts. The flexibility market would also
be open for market participants to procure
flexibility to hedge against intra-day prices
and imbalance exposure. The key features
of the flexibility market are as follows:
Buyer of flexibility: Voluntary
procurement of market participants. The
TSO would always procure flexibility for
the system needs, but the procurement
of market participants could reduce
the amount procured by the TSO.
Volume: Market participants determine
their own volume requirements, depending
on their willingness to hedge against price
risk, and the TSO provides the backstop in
the Day Ahead (DAH) auctions to ensure
that the system has the flexibility needed.
The total volume requirement of flexibility
is known through the TSO procurement
strategy, which provides stable volumes
and liquidity in the flexibility market.
Products: Multiple products (e.g. 5 min
ramping, 30 min ramping etc.) defined
by the TSO in consultation with industry
players, to ensure the needs of the system
are met. All products require an option to
deliver, and increase or decrease in physical
energy within a future settlement period.
Timeframes: The DAH timeframe
aligns (or allows co-optimisation) with
the energy market, and provides a daily
reference price for different flexibility
products. A secondary within-day market
for market participants and the TSO to
trade their options as more information
emerges. Clear DAH reference prices can
allow long-term financial contracts to
be struck between flexibility providers
and market players or the TSO.
Delivery: The option holder (market
participant or the TSO) may exercise the
option by calling for energy to be delivered
prior to gate closure. Self-provided
flexibility must provide information to
the TSO during the day as to whether or
not it will be exercised. After gate closure
any unused options would be exercisable
by the TSO in the balancing market.
Cash flows: Flexibility cleared through
the DAH auctions (other than self-provided
reserve) is paid a market clearing availability
fee (per MW) for the contract period (next
24 hours or hourly products). A utilisation
fee (per MWh) is paid upon exercise.
Unused flexibility must be offered to the
balancing market at the fixed utilisation
fee, for dispatch and payment by the TSO.
Cost recovery: The option holder
pays the availability fee to the flexibility
providers. Availability fees incurred
by the TSO could be recovered via an
information imbalance charge levied on
out-of-balance market participants.
Monitoring: The TSO would certify the
physical capability of capacity providers
seeking to offer at DAH auctions. Any
options exercised would be notified to the
TSO in the same way as physical energy.
A central Capacity market would be
established if the Energy + Flexibility
markets are not delivering investments, or
are not able to keep existing plants in the
system. The purpose of the capacity market
is to ensure capacity adequacy by providing
so-called administrative capacity payments,
which compensate for the “missing money”
from market operations. The future markets
(Energy and Flexibility) are volatile by
their nature, while investors may require
stable cash flows to be able to finance
their new projects. In this case, a capacity
market could enhance the bankability of
new projects. A capacity market (like any
capacity mechanism) should concentrate
on securing adequate capacity, rather
than specifying what type of capacity is
WÄRTSILÄ TECHNICAL JOURNAL 02.2013
17in detail
Criteria Description Evaluation
Impact on capacity adequacy
Delivers adequate peak capacity to mini-mise risks to security of supply
If required, the introduction of market wide capacity mechanism ensures capacity adequacy
Transparent and competitive market provides market based investment incentives
Impact onflexibility
Enables the value of flexibility to be trans-parently revealed, supporting the required volume of new investment
Transparent market for flexibility at the DAH stage can create a liquid reference price to support investment
Reduced imbalance exposure provides strong incentives for market to procure flexibility
SO provides a backstop to ensure that the system needs are met, and to aid liquidity
Facilitates competition, entry and exit
Encourages efficient competition and new entry, as well as retirements where this is economic
DAH flexibility market with clear reference price could encourage new entry from flexibility providers
Capacity mechanism may encourage older less flexible plant to remain on the system. Therefore essential to implement flexibility market before capacity market.
Impact on financing
Long-term bankability for investors, and ability to attract diverse range of investors and sources of finance
Flexibility market revenues allows flexible capacity to be more competitive in the Capacity Market, enhancing bankability
Investment on project finance basis may not be viable Strong cost targeting could encourage joint venture
opportunities, for example between wind developers and flexible capacity providers
Impact on affordability
Consumers pay no more than necessary to deliver decarbonisation and security of supply
All costs visible for market players Competition in all stages SO may be more risk averse than the market with respect
to both capacity and flexibility, increasing overall costs to consumers
Reliance on well-functioning wholesale market
Importance of a liquid and well-function-ing wholesale market to the success of the model
Within-day liquidity likely to be important to facilitate secondary trade in flexibility
Reliance on central decision making
Extent to which investment decisions are made by a central body
Central determination of adequacy requirement Cost of flexibility visible to market players and flexibility
market providing market based tools to hedge against imbalance risk
Complexity Complexity of the market arrangements and the subsequent investment decision
Complexity in central determination of adequacy requirement
Definition of SO role as backstop flexibility provider may be difficult to design, monitor and enforce
Need clear mechanism to reduce imbalance exposure for hedged market participants if flexibility option hold after gate closure
Table 1 – Market model evaluation.
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needed. It should be technology neutral
and treat all forms of capacity (demand
and supply) on an equal basis. A well
functioning energy market, together
with the flexibility market, would reward
capabilities when the capacity market
only provides the “all-in price” required
by investors to make the investment.
Evaluation of the proposed market design
An optimal power system provides
affordable, reliable, and sustainable
electricity to consumers. The electricity
market structure should provide incentives
to investors to invest in new power
generation that meet the set system
objectives. It is relatively easy to design
a market model meeting one or two of
the set cornerstones of an optimal power
system, or that favours some technologies
over others. To assess the feasibility and
compatibility of the proposed market
model, evaluation criteria have been
developed for this purpose. These criteria
assess the market model from different
perspectives, taking into account the most
relevant stakeholders. The developed
evaluation criteria and the high level
impact assessment are shown in Table 1.
How to make the market work
Today, the capacity mechanism is at the
center of the EU electricity debate due
to the risk of capacity shortfalls. While
continuously trying to ensure capacity
adequacy, adding flexibility to the system
should be higher on the agenda. There
are potential market based approaches
to incentivize investments in flexibility,
which do not require administrative
cash flows, but call for a reallocation
of system costs from the TSO to the
market, making the cost of flexibility
visible for market players. To develop a
reliable, affordable, and sustainable power
system, several actions are needed:
Firstly, understand that the energy
market environment has dramatically
changed due to increasing amounts
of variable RES generation, and
that this new environment requires
increased services (flexibility).
Next, recognize the value of flexibility
and make it visible for market
players through cost reflective
imbalance prices and by developing
short term energy markets.
Then create a transparent market place
explicitly for flexibility so as to enable
the efficient procurement of system
services, and to provide clear market
signals for investors in flexibility.
Finally, ensure market entry for
new players and the bankability
of new projects by introducing
a Capacity market, if the Energy
and Flexibility markets are not
delivering the investments.
To avoid the risk of “locking-in” a wrong
type of capacity, it is important to note
that the above steps are implemented
prior to this latter step can be considered.
Many market players are calling for a market
based approach regarding the EU electricity
market structure. It is possible to design an
electricity market that provides investment
signals for the right type of capacity, while
also ensuring capacity adequacy at the
same time. However, this requires a new
approach to electricity market design,
since old tools are no longer suitable in
the changed market environment.
WÄRTSILÄ TECHNICAL JOURNAL 02.2013
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Flexible energy allows efficient and cost effective integration of renewables into power systemsAUTHORS: Matti Rautkivi, General Manager, L iasion Off ice, Power Plants
Melle Kruisdijk, Market Development Director Europe, Power Plants
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A recent Wärtsilä study in UK study provides strong evidence that by introducing flexibility into power systems that have increasing levels of solar and wind sourced generation, system efficiency can be increased and consumer costs can be lowered.
The changing energy market environment
The generation mix in electricity markets
around the world is changing. Governments
are putting policies in place that address
the energy ‘trilemma’ facing their countries,
often in response to national or regional
targets that mandate a change in one or more
areas. This trilemma is widely accepted
to consist of:
Environmental sustainability:
countries need environmentally
sustainable ways of generating electricity,
without long term dependence
on burning fossil fuels that have
associated carbon emissions.
Security of supply: countries are seeking
ways to ensure that ‘the lights stay on’
in the midst of either growing demand
or old generating capacity shutting
down, which can be exacerbated by the
intermittency of renewable generation.
Affordability: increasing electricity
prices are a concern for all consumers,
and have the potential to disrupt economic
growth and throw households into fuel
poverty.
Efforts to de-carbonise and improve security
of supply often need to be balanced with
affordability. Policies for supporting
domestic industries, especially in times of
economic downturn and recession, are often
necessary. Renewable and low carbon forms
of generation have a vital role to play in the
sustainability effort, and, often, in security
of supply. The key focus for the deployment
of renewables in a 2020 timeframe is wind
and solar generation. In 2010, wind and
solar’s contribution to the world’s gross
electricity production stood at just under
3, and the IEA estimates that wind and
solar would have to grow by 16 and 21
respectively by 2020 in order to follow the
pathway required under its 450 scenario1.
The increasing need for flexibility
Wind and solar forms of renewable energy
are intermittent by nature since their
output fluctuates as a result of weather
conditions. The output from wind turbines
fluctuates with changes in wind speed,
while solar PV output fluctuates as varying
cloud cover impacts light intensity.
Without flexible forms of energy to balance
increasing intermittency, the system
could become unstable and insecure. It
could lead to the system operator taking
actions to curtail power from wind, solar
or other inflexible generation in order to
maintain system security, and in extreme
cases could also lead to black-outs.
Flexibility can be defined as the ability to change the level of
electricity output (or consumption) in response to an instruction
or another signal. All forms of electricity production or
consumption are flexible over certain timeframes. For example
a combined cycle gas turbine (CCGT) can flex from producing
no electricity at standstill to full output over the course
of a couple of hours. Similarly some industrial processes take
hours or even days to entirely shut down to bring their
electricity consumption to zero. Response time is the critical
differentiator for evaluating flexible forms of energy in
the context of balancing intermittent renewables. Flexible
forms of energy must be able to ramp their output at the
same rate that wind and solar output fluctuates, so that a
balance can be maintained. Systems need to respond across
different timeframes, from seconds to minutes to hours.
This presents an increased challenge
for parties responsible for managing flows
across the electricity networks, especially
where the output of many wind and solar
farms are correlated within an area as a
result of regional weather patterns. In
most countries this is a role carried out by
the transmission system operator (TSO).
However, it is also a challenge for energy
companies looking to ensure that the
energy that they buy or generate is sufficient
for the electricity that their consumers
need. Electricity storage technologies are
either not yet commercially developed,
or are not available in all areas (such as
forms of hydropower), so levels of thermal
generation output need to be made to
balance with levels of consumption on a
second-by-second basis. At present this
is mostly achieved by flexing the output
of controllable sources of electricity
generation, such as gas, coal, oil and hydro.
System operators hold flexibility in
reserve already to cover disturbances in
the balance of supply and demand, such as
surges in demand, or for back-up in case of
the failure of a large plant. The impact of
large amounts of intermittent renewables
on systems will need to be handled in a
similar way, though it is widely accepted
that in future the task of balancing wind and
solar generation will be far more significant.
This will mean that system operators may
have to hold significantly larger volumes of
flexible reserves than they do at present.
How can flexible energy be provided?
Flexibility in electricity markets is not a
new concept. There is already a range
of existing technologies that can provide
flexibility within the short timescales that
will be required. Some of the common
forms of flexible energy technologies are:
QUESTION: WHAT IS FLEXIBILITY?
Storage: Includes hydropower, batteries,
flywheels, pressurised gas, and other
developing technologies. Apart from
hydropower, the other technologies
are still struggling to be viably
demonstrated on a commercial scale.
Interconnection: Networks linking
adjacent electricity systems to enable
WÄRTSILÄ TECHNICAL JOURNAL 02.2013
21in detail
cross border trading of electricity –
flowing to where prices are highest.
Thermal generation: Includes
conventional turbines and reciprocating
engines, with either simple or combined
cycles. Thermal generation provides
flexibility either by running at part load
(CCGT and coal) or from stand-by mode
(gas engines, open cycle gas turbine)
Demand side response: Energy
consumers reducing their consumption
in response to an instruction or signal
(causing demand to fall to match
the available supply of electricity).
Hydropower and interconnection offer
flexibility where they are available, and
Demand Side Response (DSR) could
have significant potential in the medium
to long term. However, it is widely
accepted that thermal generation will
still be required in most systems for
providing flexible energy in the future.
The traditional way of providing flexibility from thermal sources
Many systems rely on CCGTs, or existing
coal plants, to provide flexibility. As these
plants cannot typically provide flexibility
from standstill, they often need to be
part-loaded. Part-loading is the practice of
turning down generating units that would
otherwise be running at full load, so that
they can be turned up again to provide
flexible energy if needed. Similarly,
generating units that are not running can be
turned on to produce low levels of output
as a form of standby. It is a way of creating
reserves of flexible energy, as demonstrated
in Figure 1.
However, while this may have been
practical in the past for providing small
amounts of flexibility from existing generating
resources, it is questionable whether such
practices will have the efficiency needed for
integrating renewable generation in the future.
The practice of part-loading conventional
power plants to ensure that they can provide
flexibility is a cause for concern where the
associated costs are inefficient, as these
costs will be passed on to consumers.
These costs arise for a number of reasons:
part-loading a generating unit that is
already supplying energy to customers
means paying another (probably one
with a higher cost of generation)
unit to replace the energy;
part-loading a conventional power plant
from standstill incurs large start-up costs
owing to the time and fuel required to
Fig. 1. – A way of creating reserves with plants in the spinning mode.
Normal running scheduleE
lec
tric
ity
pro
du
cti
on
After part-loading
GeneratorA
GeneratorA
GeneratorB
Generator Aat full output
Potential energy held in reserve for flexibility
Generator B paid to turn on and part-load to replace energy from Generator A
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get the unit running at a stable level, and;
part-loading of conventional power
plants, which also reduces fuel efficiency
since such plants tend to be most
fuel efficient at maximum output.
It can be shown that these costs may be
significant in some systems, and that they
could constitute an increasing proportion
of consumer bills as the level of intermittent
generation grows in electricity systems.
Countries, especially those with a high
share of renewable capacity, will need to
enable more efficient generation solutions
for providing flexible energy to reduce
these unnecessary operating costs.
A new way?
Instead of focusing on part-loaded
conventional generation to provide
the increased flexibility requirement in
the future, we believe that electricity
markets need to embrace new forms
of flexible generation, such as forms
of Smart Power Generation (SPG).
SPG fulfills a set of requirements that
Wärtsilä believes the future generators
must be able to deliver to enable the
transition to a modern, sustainable
power system. These requirements are:
very high energy efficiency,
outstanding operational flexibility, and
multi-fuel operation.
As SPG has an outstanding operational
flexibility characteristic, it can provide
the required flexibility in a new way.
Instead of running thermal plants at part
load to provide the required flexibility,
SPG could provide flexibility from
stand-by mode, due to its fast response
time and superior ramping capabilities.
Where SPG is providing the required
flexibility instead of part loaded thermal
generation, the costs listed in the previous
chapter can be avoided, and consumers
are not paying extra for flexibility.
Value of Flexibility - Great Britain case study
Wärtsilä commissioned Redpoint Energy
to undertake an analysis of the potential
savings to be derived from using SPG for
flexibility in the GB electricity system in
2020 and 2030, by which time the GB
electricity system will contain a significant
share of wind generation capacity. The
analysis looked into the cost difference for
providing flexibility from a version of Smart
Power Generation technology compared to
the current practice of using part-loading
in the Great Britain electricity market.
The GB electricity market is using
increased levels of wind sourced generation,
and the UK Government is aiming for 31 of
electricity to be generated from renewables
to meet its 2020 renewable energy targets.
Modelling of the GB market in 2020 and
2030 considered two scenarios for the
trajectory of wind generation deployment
- ‘base wind’ and ‘high wind’. In each of
these scenarios, 4.8 GW of new build CCGT
generating capacity was replaced with
4.8 GW of SPG. The modelled capacity
mixes with SPG are shown in Figure 2.
PLEXOS, a power market simulation
tool, was used to determine the least cost
dispatch of generators in the GB market,
and also to simulate the actions that
the system operator would have to take
to create the flexible reserves of energy
needed to integrate wind (known as reserve
creation). Constraints caused by the GB
network configuration were also taken
into consideration. This allowed the costs
of these actions using SPG compared to
the costs of using CCGT to be compared.
The results of the study
Taking a typical business day in 2020
from the base scenario as an example, the
chart on the left of Figure 3 shows how
the GB system operator would need to
take actions throughout the day to turn
down coal powered generation (the red
area), while simultaneously replacing this
energy with gas CCGT (the blue area) in
order to provide flexibility2. The chart to
the right of Figure 3 illustrates the system
Fig. 2 – Capacity mixes of modelled scenarios.
SPG
Other
Offshore Wind
Onshore Wind
Pump Storage
Hydro
Peaking
Gas
Biomass
Coal
Nuclear
160
140
120
100
80
60
40
20
0
GW
Base BaseHigh
2020 2030
High
WÄRTSILÄ TECHNICAL JOURNAL 02.2013
23in detail
operator’s actions in part-loading terms.
By comparison, Figure 3 and 4 shows how
the volume of part-loading is reduced when
SPG replaces CCGT in the market. The need
for flexibility has not disappeared, but rather,
because SPG can be quickly dispatched from
standstill in response to fluctuations in wind,
there is a reduced need to take actions to
prepare flexible sources of energy through
the part-loading of conventional generators.
In a conventional plant, high volumes of
part-loading are still required across peak
periods of the day (07:00-11:00, and 15:00-
21:00), partly because market prices at these
times are driven to levels where it is
economic to sell SPG output on the market,
which means it is unavailable to provide
flexible energy. This is shown in the dispatch
of different generating technologies on the
market across the typical day in Figure 4.
The proportion of flexible reserves
provided by SPG across all the modelled
years and scenarios is shown in Figure 5.
Where SPG is included in the system, it is
the single biggest provider of flexibility, and
the most economical option in all the years
and scenarios modelled, thus mainly having
the impact of displacing the use of gas
CCGT and coal for providing flexibility.
Fig. 3 – Actions taken for flexible reserve creation without and with SPG.
Normal running schedule
Ele
ctr
icit
y p
rod
uc
tio
n
After partloading
Coal generation
Coal generation
Gas generation
Gas generation
Coal generation
running at full
output
Coal generation
part-loadedto create flexibility
Gas generation turned on
to part-load to replace
energy from coal
Flexibility made
available
4
3
2
1
0
-1
-2
-3
-4
GW
Gas
Coal
00:00
08:00
12:0
016
:00
20:00
04:00
Normal running schedule
Ele
ctr
icit
y p
rod
uc
tio
n
After partloading
Coal generation
Coal generation
Gas generation
Gas generation
Coal generation
running at full
output
Coal generation
part-loadedto create flexibility
Gas generation turned on
to part-load to replace
energy from coal
Flexibility made
available
4
3
2
1
0
-1
-2
-3
-4
GW
Gas
Coal
00:00
08:00
12:0
016
:00
20:00
04:00
Actions taken for flexible reserve creation (no SPG)
Actions taken for flexible reserve creation (with SPG)
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Savings in the provision of flexibility
In GB, the costs of reserve creation are
recovered as a charge collected from
market participants, which are passed
on to consumers. AS SPG reduces the
need to create reserves by part loading
thermal plants, it produces considerable
savings, which are set out in Table 1.
This modelling indicated that significant
savings in managing the costs of
intermittent wind output could be possible.
Compared to using current practices,
we estimate savings of between GBP 381
million to GBP 545 million per annum in
2020 under different scenarios, and the
modelled savings are estimated to be as
high as GBP 1537 million per annum in
2030 by when the GB system will contain
more intermittent renewable capacity.
As consumers are the ones to ultimately
carry the costs of power system balancing,
using SPG results in significant savings
for consumers. Also, the study shows
clearly that the amount of savings
increases rapidly with increasing wind
penetration. As the share of intermittent
renewables is bound to grow according to
the current policies in several countries,
the value of flexible generation must be
understood when forming future energy
policies and market design principles.
[1] The IEA’s 450 scenario outlines an energy pathway that would limit the concentration of greenhouse gases in the atmosphere to a level of 450 parts CO2 per million.IEA 2011 , “Deploying Renewables: Market development for RE technologies”. IEA 2012, “IEA statistics: Electricity Information 2012”.
[2] The modelling assumptions were such that electricity produced from coal was calculated to be lower in cost than electricity produced from gas, meaning that coal was already on the market and available for being turned down to part-load.
Table 1 – Costs of creating flexible energy (reserve) with and without SPG.
Fig. 4 – System generation with SPG.
Fig. 5 – Proportion of system flexibility provided by different technologies.
GW
Interconnertors
SPG
Other
Offshore Wind
Onshore Wind
Pump Storage
Hydro
Peaking
Gas
Biomass
Coal
Nuclear
Demand
60
50
40
30
20
10
0
10/03/202004:00
10/03/202012:00
10/03/202020:00
10/03/202008:00
10/03/202016:00
10/03/2020
Pro
po
rtio
n o
f Sys
tem
Fle
xib
ility
No SPG
No SPG
No SPG
No SPG
Base BaseHigh High
2020 2030
With SPG
With SPG
With SPG
With SPG
100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%
SPG
Pump Storage
Hydro
Peaking
Gas
Biomass
Coal
Balancing costs – flexibility provision
(£ mn per annum, real 2011 )
2020 2030
Base Wind High Wind Base Wind High Wind
Cost – No SPG 692 1008 834 2781
Cost – With 4.8 GW SPG 311 464 256 1244
Cost Saving due to SPG 381 545 578 1537
WÄRTSILÄ TECHNICAL JOURNAL 02.2013
25in detail
A new service agreement solution for peaking power plantsAUTHOR: Kim Lindqvist , Suppor t & Development , S ervice Agreements, Wär tsi lä S ervices
Stefan Malm , Product S olut ions & Engineering , Wär tsi lä Power Plants
Fig. 1 – Condition monitoring and maintenance planning enable optimisation of lifecycle costs.
A service agreement is more than merely an effective way for ensuring the certainty of operations. It signifies the long-term co-operation of both parties in working towards a shared goal. Wärtsilä works hard to develop service agreements that meet the specific needs of customers.
A service agreement enhances business
With a tailor-made agreement, the
customer signs up for not only a long-
term partnership with Wärtsilä, but
also to achieve improved reliability and
availability. It also means maximised
lifetime for the installation and reduced
operational costs in a safe, reliable, and
environmentally sustainable way.
Technical expertise – locally and globally around the clock
Only a company with a global service
network has the capability to employ local
people to execute the agreement wherever
required. In terms of customer relations
it is important that the personnel speak
the local language, understand the culture
and build trust among customers.
An agreement also minimises the points
of contact for maintenance calls. Individual
equipment suppliers need not be contacted,
since Wärtsilä co-ordinates all maintenance
requests and provides easy access to
Wärtsilä’s local and global knowledge base.
A service agreement ensures certainty of operations for peaking power plants
Owners of peaking power plants expect
trouble-free operations from the facility.
During the first three years of operation, the
new Wärtsilä service agreement solution
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Fig. 2 – With a Wärtsilä customer support engineer on site, operational support is immediately available.
WÄRTSILÄ TECHNICAL JOURNAL 02.2013
27in detail
Please check Wärtsilä
Services Solution Studio,
Condition Monitoring:
www.wartsila.com/en/
solution-studio
provides onsite customer-support personnel,
scheduled and unscheduled maintenance,
as well as condition monitoring to
optimise the performance, availability, and
reliability of the asset. In short, the added
value means that the operator can focus
on his core business. A partnership with
Wärtsilä provides that peace of mind.
An investment in a peaking power
plant is mostly derived from the need
to occasionally compensate for a lack of
available electricity. A Wärtsilä service
agreement solution backed up with a
prolonged warranty, valid from the first day
of commercial operation, provides reduced
risk for the customer’s investment and
operations. Ensuring certainty of operations
also provides several other benefits, such as
increased efficiency and cost predictability.
An agreement is a sound investment
There are often significant seasonal, weekly
and daily variations in power demand. In a
multi-unit power plant the units can be
started and stopped as per power demand.
This means that the annual average unit
running hours, depending on the actual
load profile, can be considerably lower than
the annual plant running hours.
Especially in case the load profile varies
significantly, the influence on the maintenance
costs is considerable. In a multi-engine plant
the units can be dispatched, so that the
running hours are unequally spread on each
unit. This concept allows for scheduling the
maintenance one unit at a time, thereby
maximising the available power generation
capacity at any given time. Ideally, the
maintenance is scheduled at periods of
lower power demand. A Wärtsilä service
agreement is a sound investment since it
can directly impact the overall operational
efficiency of the plant. Moreover, this type of
agreement brings several other considerable
benefits. These include optimised and fixed
operational costs; improved operational
reliability; maximised uptime; dedicated
technical expertise and support from a
global network of skilled service experts;
minimised downtime through proper
maintenance and co-ordinated schedules;
online condition monitoring; and the
availability of OEM parts and consumables.
The right solution for peaking plants
This new solution is designed with the needs
of the customer in mind. Not all peaking
power plant customers are familiar with
Wärtsilä technology, nor do they all have
experience of working with the company.
This new service agreement solution is,
therefore, aimed at ensuring that the
customer's investment is secure and
predictable. By building a strong and
trusting partnership with the customer,
operational costs can be accurately estimated
and additional costs avoided. The service
agreement extends the warranty period of
the equipment and ensures that the
customer receives the highest level of support.
In short, the availability and reliability
of the plant will be maximised. All technical
support, maintenance planning, and safety
spare parts management planning is
customised according to the customer's
specific requirements.
On site operational support
A peaking power plant may operate for
many hours a day or for only a few hours
per year. Whatever the case, it is vital that
the plant has the ability to quickly reach
full capacity under all conditions. With
a Wärtsilä customer-support engineer
on site, the operator can be assured of a
reliable plant start-up. It also means that
fast and efficient communication with
Wärtsilä’s technical expertise is maintained.
The onsite customer-support engineer
also serves to minimise the number of
contact points for maintenance calls.
Maintenance planning to support the operating profile
Wärtsilä specialises in customised
maintenance agreements designed
specifically to meet the operational
requirements of individual power plants.
The company’s new agreement for peak-
load plants features prolonged warranty
coverage and a multi-portfolio services mix.
The improved forecasting of maintenance
needs, and the overall function of the
system, are achieved through the remote
monitoring, measuring, and analysis of
engine parameters. Wärtsilä’s technical
support and maintenance planning teams
offer unrivalled resources and know-how
for keeping equipment online and reducing
downtime. Data is analysed and trends
and changes in operating parameters can
be identified well before they might
compromise the performance of
the installation.
A cost-predictable future
Although savings are always important, it is
cost predictability that becomes even more
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vital when dealing with long-term business
performance. With OPEX predictability over
a longer period of time, lifecycle costs can
be forecasted accurately, and maintenance
expenses for the coming years can be
accurately budgeted. Part of this is achieved
through the inventory management of the
customer-owned onsite safety stock, which
is there to support the operating profile.
Preventing the unexpected
This service agreement is available for
new gas-fired peaking power plants in,
among other places, the USA, Europe, and
Australia. The service agreement is valid
from the first day of commercial operation.
A Wärtsilä service agreement is a proven
way of preventing the unexpected, and
keeping the installation productive and
profitable – throughout the entire lifecycle.
A peak-load maintenance agreement
provides optimised performance, and
includes a long-term warranty, an onsite
customer-support engineer with OEM
expertise; OEM services, inventory
management and remote monitoring to
improve reliability; OPEX predictability;
maintenance planning; and optimised
maintenance and logistics.
The basic idea behind a maintenance
agreement for peaking power plants with
Wärtsilä is long-term cooperation, where
both parties work towards a shared goal,
namely the company’s continued
productivity – and profitability.
What are the specific needs?
With more than 17,600 MW under service
agreements, and more than 500 installations
covering a wide variety of land-based,
marine and offshore installations being
operated and maintained by Wärtsilä, the
company is widely recognized as being
the preferred service supplier by customers.
These agreements ensure the availability and
cost-efficient operations of their installations.
Wärtsilä offers four types of standardised
agreements, ranging from supply agreements
to technical management, as well as
maintenance agreements and complete
asset management support. However, all
agreements are customised to fulfil each
customer’s specific needs.
Highlights of a maintenance agreement for peaking power plants
Long-term warranty coverage.
Available for new gas-fired peaking
power plants
Dedicated technical support. Customer-
support engineer with OEM expertise
ensuring fast and efficient communications
Condition monitoring to enable trending
and optimization of equipment
performance
Maintenance management. Maintenance
planning to support the operating
profile. Management of customer-
owned onsite safety stock.
Fig. 3 – Wärtsilä offers four types of standardised agreements.
WÄRTSILÄ TECHNICAL JOURNAL 02.2013
29in detail
EXAMPLE
– A FLEXIBLE POWER PLANT WITH A MAINTENANCE AGREEMENT: THE STEC RED GATE POWER PLANT, SOUTH TEXAS ELECTRIC COOPERATIVE
Powered by 12 Wärtsilä 50SG engines running on natural gas having a total output of 225 MW
Flexibility, quick start-up capability, superior load following, and favourable lifecycle costs
High efficiency engines result in fewer emissions of CO2 than simple cycle gas turbine solutions
High simple cycle efficiency achieved with minimal water consumption
Maintenance Agreement
The agreement provides a number of benefits:
Optimised maintenance for long-term plant availability, reliability, and efficiency
Technical and operational assistance with maintenance planning, technical advisors, spare parts, and an on-site inventory
Technical, parts and risk sharing support
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The tanker M/T Samurai.
Improving VLCC propulsion fuel efficiency with the Wärtsilä X82 engine
AUTHOR: Heinrich Schmid, General Manager Appl icat ion Development , Ship Power
WÄRTSILÄ TECHNICAL JOURNAL 02.2013
31in detail
With fuel costs currently responsible for
70 to 85 percent of the total costs of operating
vessels, it is hardly surprising that owners and
operators are demanding greater fuel
efficiency. From an average HFO price of
some USD 150 per ton in 2001, prices steadily
rose to an average close to USD 700 per ton
in 2012. Clearly, in order to keep running
costs at a justifiable level, greater fuel
efficiency is needed.
In addition to having to meet the
challenge of high operating costs, owners and
operators are also increasingly confronted
with environmental compliance requirements.
Despite the maritime industry’s claim that
shipping is the most environmentally
friendly mode of transportation it is,
nevertheless, under considerable pressure
from policy makers, regulatory bodies, and
even the general public to reduce emissions.
Since the level of emissions is directly related
to fuel consumption, it is essential that
today’s marine engines achieve the greatest
possible fuel efficiency.
The Wärtsilä X82 engine offers parameters
that meet this need.
The Wärtsilä X82 engine
The Wärtsilä X82 engine is the upgraded
version of the RT-flex82T engine. The
X82 engine was previously also known as
the RT-flex82T-B. The RT-flex82 engine
series was introduced in 2006; the short
stroke version as the RT-flex82C, and the
long stroke version as the RT-flex82T.
Following the accumulation of positive
service experience with the 82T version,
the X82 (RT-flex82T-B) engine was
introduced in 2011 as the upgraded version
with the following adaptations:
Mep increased from 20.0 bar to 21.0 bar
R1 + speed increased from
80 rpm to 84 rpm
R2/R4 speed reduced from 68 to 65 rpm
R4 power reduced to the same mep as R2
The physical shape of the engine is
characterised by its slim appearance, with
the fuel supply pumps arranged with
convenient accessibility close to the engine.
The electronic fuel injection and exhaust
valve control system is based on Table 1 – Parameters of the Wärtsilä RT-flex82T and Wärtsilä X82 engines.
Fig . 1 – The Wärtsilä two-stroke engine portfolio.
In order to reduce operating costs, fuel efficiency is essential. The new Wärtsilä X82 engine with its 65 to 84 rpm speed range is perfectly suited for optimal VLCC (Very Large Crude Carrier) operations.
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Fig. 3 – The rating fields of the Wärtsilä RT-flex82T and Wärtsilä X82 engines.
5000
RT-flex82T
4800
4600
4400
4200
4000
3800
3600
3400
3200
3000
280060 65 70 75
Speed (rpm)
Po
we
r p
er
cyl
ind
er
(kW
)
80 85 90
X82
R1 4750kW
4520kW
R1+
R1
R1+
Fig. 2 – The Wärtsilä RT-flex82T engine.
WÄRTSILÄ TECHNICAL JOURNAL 02.2013
33in detail
the highly efficient, simple and reliable
common rail technology. The common
rail platform, with its fuel injection and
exhaust valve actuation elements, is
arranged to provide good accessibility
at the engine’s upper platform level.
The rating field is characterised by the
R1+ / R2+ rating points, which offer the same
power as at R1 & R2 but at a higher speed.
The R1+ rating point features a 2 g/kWh
lower specific fuel consumption than the R1.
This R1+ rating field allows shipyards greater
freedom for propeller tuning (see Figure 3).
The Wärtsilä X82 offers an engine speed
as low as 65 rpm at R3 / R4 with a moderate
stroke to bore ratio of 4:12.
Wärtsilä’s common rail engine operating system
Electronically controlled fuel injection and
exhaust valve timing enables optimum
combustion under all circumstances.
The common rail system allows the fuel
nozzles to be individually activated. They
can be either sequentially operated so as to
influence NOX emissions or, alternatively,
one or two nozzles per cylinder can be
switched off to achieve an efficient and clean
combustion for low load operation. In single
nozzle mode, a stable engine speed of about
10 – 12 percent of the nominal engine speed
is possible.
To date, approximately 1000 Wärtsilä
RT-flex common rail engines have been
ordered, of which some 600 are already in
operation (Figure 4). For Very Large Crude
Carrier (VLCC) ships, the RT-flex82T engine
is reputedly the most popular choice of
engine.
Fig. 4 – The common rail engine operating system.
Fig. 5 – The VLCC "Crudmed" is powered by the first Wärtsilä RT-Flex82T engine.
Crankanglesensor
Controlsystem
Exhaust valveactuator
Fuelinjectors
Volmetric fuel injection control unit
Exhaust valveactuating unit
up to 1000 bar fuel HFO / MDO
200 bar servo oil and control oil
30 bar starting air
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Fig. 8 – Definition of the propeller design point.
Fig. 6 – Impact of propeller speed on the propellers optimal diameter and propulsion efficiency.
Fig. 7 – Selection of the optimum propeller speed.
60
65
70
75
80
85
90
95
100
105
110
115
120
88 90 92 94 96 98 100 102 104 106
Engine/Propeller speed (%)
99.0% 100.9%
Po
we
r (%
)
Nominal propeller curve
CMCR power
CSR = 90% CMCR power
CSR = 85% CMCR power
Propeller curve with 4.5% LR margin
Propeller design points
4.5% LR margin
WÄRTSILÄ TECHNICAL JOURNAL 02.2013
35in detail
Fig. 9 – Typical open water propeller efficiencies for different propeller diameters.
Fig. 10 – The wake fraction and thrust deduction correction as a function of vessel length and propeller diameter, as proposed by S.A. Harvald.
Propulsion aspects
The efficiency of the daily fuel consumption
is defined as a result of the efficiency of
the propulsion system, and the specific
fuel consumption of the propulsion
machinery, i.e. the engine’s efficiency.
Propulsion efficiency is defined by
the following propulsion factors:
Open water propeller efficiency (η0)
Relative rotative efficiency (ηR)
Hull efficiency (ηH = (1-t)/(1-w)
Mechanical efficiency (ηM)
Propulsion efficiency ηP = η0* ηR* ηH* ηM
Propulsion efficiency is influenced by
the propeller speed and diameter
(Figures 6 & 7).
It is assumed that the relative rotative
and shaft efficiencies are not influenced
by variations in the propeller speed and
are, therefore, neglected for this study.
The engine’s fuel efficiency (specific fuel
consumption) is influenced by the ratio
between the maximum and mean effective
pressures. The higher the ratio, the higher
the fuel efficiency, i.e. increasing the pmax/
mep ratio results in lower specific fuel
consumption. Reducing the engine speed for
a defined power increases the mean effective
pressure and, therefore, also increases
the engine’s specific fuel consumption.
The following must be considered when
calculating the best propulsion efficiency:
Any variation in propeller diameter
(and speed) affects the open water
efficiency of the propeller.
Variations in the diameter of the
propeller affect the wake fraction
w and the thrust deduction t and,
therefore, the efficiency of the hull.
Variations in the engine / propeller
speed affect the engine’s specific fuel
consumption.
As mentioned earlier, the combination of
propulsion efficiency and engine efficiency
decides the daily fuel consumption. In
order, therefore, to achieve the best fuel
efficiency, it is important to take into
consideration changes in the propulsion
parameters (η0, ηH, BSFC) resulting
from variations in the propeller speed.
Propeller design point
It is assumed that the propeller is
optimised for light running conditions at
CSR power (see Figure 8). With that, the
propeller design point becomes roughly
the CMCR speed of the main engine.
Open water propeller efficiency
The open water efficiency of the propeller
is basically affected by its speed and
diameter. As a general rule, the larger the
propeller diameter, the higher the propeller
efficiency and the lower the propeller
speed. Since there is usually a limitation
in the diameter of the propeller due to
the draught of the vessel, the optimum
propeller speed is defined by the maximum
possible propeller diameter (Figure 7).
The difference in the open water efficiency
of the propeller can become as much as
5.3 for a VLCC, such as when comparing
a 10.9 m propeller running at 60 rpm and
a 9.4 m propeller running at 76 rpm.
The alpha-factor expresses the relative
power at a constant ship speed to
variations in the propeller’s speed and
diameter. For the reference case below,
the alpha-factor has a value of 0.23 within
a relevant propeller speed range of 60 –
76 rpm for VLCC propulsion. (Figure 9)
The open water propeller efficiency
calculation is based on the following:
CMCR power = 24,000 kW, CSR = 85,
w = 0.316, t = 0.265, 4 blades,
BAR = 0.45, 15.5 knots service speed,
5.5 LR margin.
Hull efficiency
Hull efficiency (ηH) is defined by the wake
fraction w and the thrust deduction t.
ηH = (1- t)/(1-w)
Wake fraction and thrust deduction can be
influenced by the diameter of the propeller,
as proposed by S.A.Harvald (Figure 10).
0.10
0.10
0W3 t3
tW
0
+ +
0.10
0.10
VLLC Range
0.02 0.03 0.04 0.05 0.06
D/L
0.07
Propeller diameter correction
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Due to the larger propeller, the wake fraction
becomes slightly lower and the thrust
deduction slightly larger. Thus, the larger
the propeller diameter, the lower the
hull efficiency becomes (Figure 11).
The Hamburg Ship Research Institute
(HSVA) has also studied the impact of
variations in propeller diameter on the
propulsion parameters. Contrary to
Harvald’s suggestion, HSVA proposes that
the thrust deduction is not affected by
changes in the diameter of the propeller, but
only by the wake fraction (see Figure 12).
For further study, the mean values from
both Harvald’s and HSVA’s proposals shall be
taken into consideration. The impact on the
change of propulsion parameters relative to
the propeller diameter is shown in Figure 13.
To ascertain the total propulsion
efficiency one should, therefore, not only
Fig. 11 – The impact of the propeller diameter on the propulsion coefficients according to Harvald´s proposal.
Fig. 12 – Impact of the propeller diameter on the propulsion coefficients according HSVA´s proposal.
consider the effect of the propeller diameter
on its open water efficiency, but the product
of the open water and hull efficiencies η0*
ηH, should also be taken into account.
With the propeller diameter adapted wake
fraction and thrust deduction, the alpha
factor becomes only 0.13, (Figure 14). This is
considerably less than the 0.23 alpha factor
found for the open water propeller efficiency
alone. This shows that the negative effect of
a smaller propeller at higher rotation speed
is not as large as one would conclude when
considering only the open water efficiency.
Engine specific fuel consumption
The engine has a defined specific fuel
consumption at its maximum power R1.
When the engine is derated within the
rating field, the BSFC can be reduced. The
cylinder pressure remains constant within
-3.50-3.00-2.50-2.00-1.50-1.00
-0.500.000.501.001.50
2.002.503.003.504.00
Propeller diameter (mm)
Comparison of wake fraction 1/(1-w), thrust deduction (1-t) and etaH(as proposed by S.A.Harvald)
Increasing flexibility in LNG fuel handling – the LNGPacTM ISO
AUTHORS: Jonatan Byggmästar, Development engineer, Fuel Gas Handl ing , Ship Power
Sören Karlsson, General Manager, Fuel Gas Handl ing , Ship Power
The option of having LNG as fuel for a variety of different ship types is already available. Emission reduction requirements and cost competitive gas prices are the main driving forces behind this increasing trend towards LNG. The LNGPac™ ISO, a fuel gas handling system based on removable LNG fuel tank containers, is a new way of making LNG fuel available when a stationary tank solution is not possible.
Fig. 1 – LNGPacTM
ISO layout arrangement from LNG fuel tank containers to the GVU-EDTM
.
WÄRTSILÄ TECHNICAL JOURNAL 02.2013
43in detail
Wärtsilä LNG fuel tank container Standard ISO tank container
Standard ISO frame
Compliance with transportation regulations (IMDG, TPED, ADR, RID, CSC among others)
Compliance with rules for use as LNG fuel tank on board ships:
IMO Type-C tank
Water spraying system
Tank safety relief valves designed for fire case
Connection to external vent mast
LNG leakage detection and protection
Class approved equipment & design
Stainless steel outer shell
Dry disconnect quick couplings
Connections at end for connecting to ship
Connection to automation system on the ship
Connection to safety systems on the ship
for stationary applications. The frame
standard size dimensions and the
modularised skid-based fuel gas handling
system make installation fast and cost
competitive.
LNGPac™ ISO
The LNGPac™ ISO is a fuel gas handling
system based on mobile LNG fuel tank
containers. Besides the LNG fuel tank
container, the system consists of a docking
station and an evaporator skid installed
permanently on the ship. The LNGPac™
ISO is intended to be installed on an
open and naturally ventilated deck.
Tank containers intended for the
transportation of cryogenic liquids, e.g.
LNG, are an alternative for use as fuel
storage tanks onboard LNG fuelled ships.
However, a normal tank container intended
for transporting LNG cannot be used since
it does not fulfil all the requirements for
marine LNG fuel tanks. Modifications
relating to remote monitoring and safety
systems, IMO type C tank requirements,
and leakage & spill protection are a
few items that need to be specifically
considered for marine fuel tanks.
LNG fuel tank containers
Removable and transportable LNG fuel
tank containers are used as fuel tanks in
Table 1 – A standard ISO tank container used for transport of cryogenig fluids does not fulfil the requirement of a LNG fuel tank on a ship.
the LNGPac™ ISO fuel gas handling system.
The containers, which are designed to fulfil
all marine LNG tank requirements, are of
standard ISO frame dimensions (20 ft, 40
ft and 45 ft) and can be transported by
road, rail and sea, although the maximum
gross weight may vary in different
countries for land transportation.
The fuel tank is an IMO type C pressure
vessel enclosed within an outer tank. Both
the inner and the outer tanks are made
of stainless steel, which means that the
outer enclosure will act as a secondary
containment. The LNG fuel tank container
is fitted with process equipment, namely
the valves and instruments required
for operational and safety purposes.
The LNG fuel tank container is also
fitted with a pressure build-up evaporator
(PBE) for building up and maintaining an
operational pressure of approximately 5
bar in the tank. The pressurized tank is
used instead of having rotating equipment,
such as pumps and/or compressors to
feed the gas to the engines. Having a
PBE on the container makes the LNG fuel
tank containers completely redundant.
If, for some reason, a container is
out of service another container can
be easily taken into operation.
The connection points are located at
the end of the LNG fuel tank container
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unloading the LNG fuel tank containers.
The containers are located on cassettes
and secured by twistlocks. On board the
ship the cassette is secured to the deck,
for example with twistlocks and lashing
as a secondary fastening arrangement.
Another possible fastening and securing
option is to directly secure the LNG fuel tank
container with twistlocks and lashing to the
deck. This would be a suitable solution for
container feeders and other vessels where
the containers can be lifted on and off. It
is also possible to utilize these containers
as stationary LNG tanks, which are not
removed frequently for filling. In this
case, a bunkering station can be installed
to allow the LNG fuel tank container to
be bunkered directly on the vessel.
for easy and smooth hook-up of the LNG
fuel tank container to the onboard fuel
gas handling system. These connections
consist of the LNG discharge, the vent mast
connection, heating media connections,
and a connection to the water spraying
system built onto the LNG fuel tank
container. For fuel tanks located above
deck, a water spray system is required
to cool the LNG tank in case of fire.
Fastening and securing
The LNG fuel tank containers have to be
rigidly fastened and secured to the deck.
The fastening and securing system has to
be designed for the maximum dynamic and
static inclinations, as well as the maximum
accelerations, of the vessel. A number
of feasible solutions exist. On RoRo and
RoPax vessels it is possible to use terminal
tractors with trailers for loading and
Docking station
The docking station is the module
whereby the LNG fuel tank containers
are connected to the fuel gas handling
system onboard the ship. The number
of LNG fuel tank container slots in the
docking station is defined according to
the required LNG capacity for the specific
vessel. The engine gas consumption, sea
voyage length, and the interval between
changing the containers defines the required
number of LNG fuel tank containers.
All the necessary connections between
the LNG fuel tank container and the fuel
gas handling system are located in the
docking station for easy and practical
connecting operations. Flexible hoses
fitted with quick couplings are used to
WÄRTSILÄ TECHNICAL JOURNAL 02.2013
45in detail
Fig. 2 – Terminal tractor loading LNG fuel tank containers onboard a RoRo ship.
attach the process connections. The quick
couplings have a closing valve in both
coupling units to prevent any leakage when
connecting and disconnecting the hoses.
The instrument readings and control
signals for the remote controlled valves on
the LNG fuel tank container are connected
to a junction box in the docking station.
There is a data connection and a hard wired
cable connection for increased safety.
Preparation of the gas
The LNG is discharged from the fuel tank
containers via the docking station to the
evaporator skid. The evaporator skid is the
module where the LNG is vaporized and
heated to the conditions required by the
engine (i.e. 0 – 60 °C). The master gas fuel
valve, which is the last safety related stop
valve in the gas supply system outside the
machinery spaces, is installed after the main
gas evaporator on the evaporator skid.
The LNGPac™ ISO is controlled and
monitored by a control and safety
system. All modules, including the LNG
fuel tank containers, are monitored
and controlled by a single dedicated
PLC-based automation system.
Ship arrangement
The LNGPac™ ISO is intended to be located
on an open deck where natural ventilation
is ensured at all times. Drip trays must be
installed under the skids, and also under
the hose connections between the LNG fuel
tank containers and the docking station.
This is to prevent possible LNG leaks from
damaging the deck beneath the skids.
Design and feasibility study
A design and feasibility study has been
conducted together with Germanischer
Lloyd (GL) for the conversion of a RoRo
vessel to gas using the LNGPac™ ISO as the
fuel gas handling system. Four LNG fuel
tank containers, the docking station, and
the evaporator skid were located on the
naturally ventilated aft deck. The LNG fuel
tank containers were located on cassettes,
and secured with twistlocks and lashing.
A second set of LNG fuel tank containers
would be refilled in advance so as to be
ready for switching with the empty LNG fuel
tank containers when the ship is in port.
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LNG fuel tank container 20 ft 40 ft
Frame dimensions (external)
Length m 6058 12,192
Width m 2438 2438
Height m 2591 2591
Tank
Geometrical volume (approx, room temp.) m3
20 40
LNG volume (80 % effective volume) m3
16 32
Other sizes on request.
Fig. 3 – LNG fuel containers loaded and connected to the onboard fuel gas handling system.
Table 2 – Typical characteristics of LNG fuel tank containers of different sizes.
WÄRTSILÄ TECHNICAL JOURNAL 02.2013
47in detail
In the area where the fuel gas handling
system was located, potential existing
ventilation inlets and outlets, as well as
the electrical equipment, would have to
be modified due to the hazardous zones
around the fuel gas handling system.
For protection of the surrounding ship
structures, and for weather protection
of the equipment, the docking station
and evaporator skid would be located on
drip trays in naturally ventilated shelters.
Escape routes were planned from all
areas, especially from the docking station
where the flexible hose connections to the
LNG fuel tank containers were located.
As part of the study, a comprehensive
risk analysis was performed of the fuel gas
handling system. A risk analysis is required
for a gas fuelled ship where operational
risks and risks associated with physical
arrangements are indentified and eliminated
or mitigated. The major hazard for a fuel
gas handling system on a ship is LNG
leakage, and the subsequent damage to the
vessel. Where LNG leakages can occur, two
important things have to be incorporated
into the design. Firstly, no damage that
can harm the integrity of the ship can be
allowed to happen. Secondly, there has to
be a way to detect and identify the leakage
in order to stop and limit the leakage
and the consequences. Potential leakage
sources were identified for the LNGPac™ ISO
modules and corrective actions were taken.
CONCLUSIONS
Wärtsilä is today recognized as a leader
in propulsion solutions for gas fuelled
vessels. The company's strong and early
commitment to this goal has created in
depth knowledge of the use of natural gas
and LNG. The Wärtsilä LNGPac™ ISO is an
addition to Wärtsilä’s portfolio of solutions
for the LNG fuelled ship market. It represents
further proof of Wärtsilä’s expertise and
knowledge of LNG applications, as well
as its dedication to make LNG available
for all ship operators and owners.
Fig. 4 – Environmentally friendly RoRo vessel sailing on gas.
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Sustainable Business is the current business
model that most larger global organisations
are following. But what is a sustainable
business model? Sustainable business is
how an organisation creates, delivers, and
captures value in a truly sustainable way. It
is a means of delivering commercial success
while also being aware of the environment,
and of delivering products and services
that improve people’s quality of life.
Integral parts of this concept include
energy savings, risk management, and
sustainable development. New technologies
and operational requirements bring
ever increasing importance on knowing
exactly the competence level of the people
employed, and their ability to perform
effectively and efficiently. The Wärtsilä
Instructor assessment of auxiliary systems simulator operation exercise.
How do we know what you know? A perspective on professional skills managementAUTHORS: Peter Lancaster, Manager, Training S ales Suppor t
Matti Olli , General Manager, Training S ervices
A regulated competence assessment programme can result in operational cost savings for ship owners or power plant operators. Wärtsilä has in place solutions to the question of how to assess the technical knowledge and skills needed to achieve company goals.
WÄRTSILÄ TECHNICAL JOURNAL 02.2013
49in detail
Land & Sea Academy (WLSA) has been
instrumental since 2002 in establishing and
developing internet based processes and
tools that aid Wärtsilä’s global technical
training infrastructure. The increasing use of
Human Capital Development Management
Systems (HCDMS) and Competence &
Career Development Management Systems
(C&CDMS) by larger global organisations is
well known. However, an essential element
that is not usually included in the supply of
the software platform is an application for
assessment and, most importantly, the
content and methodology for carrying
out this assessment.
Assessment is an essential part of the competence loop
Effective implementation of SEEMP and integration with maintenance managementAUTHORS: Andreas Wiesmann , General Manager, Innovation & Business Development , 2-stroke
Tage Klockars , Director, Suppor t and development , Marine Agreements
There has already been tremendous interest in Wärtsilä’s recently introduced solutions and services supporting ship owners in the implementation of an effective Ship Energy Efficiency Management Plan (SEEMP). The next steps will focus on developing the package further and integrating it into the service agreements offered.
WÄRTSILÄ TECHNICAL JOURNAL 02.2013
55in detail
Fig. 1 – Ballast water management and reporting.
By continuously calculating a “combinator
curve”, the engine revolutions and propeller
pitch (in case of a controllable pitch
propeller) can be adjusted to meet changing
load conditions. Vessel speed and voyage
planning also play a very important part.
A Wärtsilä survey showed that some 40
per cent of ship operators were not aware
of the fuel savings that an SEEMP could
create. Wärtsilä has identified savings
from operational improvements of up
to 9 per cent, depending on vessel type,
machinery configuration and condition
and the current operations. Its SEEMP
package is a data gathering, optimisation
advisory and management tool that helps
ship owners achieve these potential savings
and at the same time manage the ongoing
environmental performance of their vessels.
In response to the new requirement
coming in force earlier this year and
to the findings of its investigations,
Wärtsilä set out its capabilities in helping
shippers to both meet and implement
the requirements. It introduced an
SEEMP package aimed at improving
fuel efficiency, reducing environmental
impact, and optimising ship handling. The
offering will also be integrated into the
company’s marine service agreements.
Combining SEEMP implementation, efficiency optimization and maintenance strategies
The mentioned tool is designed to obtain
data from ships and feed it into Wärtsilä’s
Optimiser platform, where it can be
analysed. The company has developed
the system for the last two years, which
included ways of communicating with
ships and retrieving data in order to
enable data analysis for various needs,
particularly for two main directions:
continuous performance and efficiency
optimization on one side and continuous
lifecycle maintenance cost optimization
through implementation of condition based
maintenance (CBM) on the other side.
The aim of combining efficiency
measurements with condition monitoring
and the maintenance systems is an
optimized overall asset management.
This integrated approach makes sense in
many ways. For example, monitoring fuel
consumption and making adjustments not
only allows savings in fuel costs, but also
provides an indicator of things such as
engine health, propeller or hull efficiency.
Such indications in turn help to predict
when and what type of maintenance
will be needed.
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Fig. 2 – Weather routing application on dashboard.
Taking SEEMP to additional efficiency improvements
The so far highlighted solutions focused on
the continuous improvements through
operational measures and smart maintenance
management.
Changes in the vessel speed and operating
profile and the availability of improved or
innovative technologies can offer additional
opportunities to incrementally improve a
vessel’s efficiency by retrofitting solutions.
Particularly the merchant fleet, and as a
forerunner the container shipping industry,
have substantially reduced the average
speeds. Although reduction of speed already
achieves by itself a huge saving on the
annual fuel bill, the vessels’ efficiency is not
optimized in these lower speed ranges.
Two thirds of the world’s container,
tanker and bulker fleet are younger than
10 years. Majority of these ships were
designed to operate at much higher
speeds than what is today the “new
operational reality”. Compared to optimized
vessel designs matching the new speed
requirements and having installed latest
technology equipment, so called “eco”
vessels, there is an efficiency gap of 10-25
per cent on the existing fleet. Wärtsilä
has identified measures and solution
packages that could achieve 10-20 per cent
of additional fuel savings by retrofitting.
One of the focus areas has, therefore, been
to put together a programme of “more
radical” fuel cost reduction upgrades.
There are a lot of specific solutions
where smaller percentages can be gained,
but by combining several solutions
and tailoring such packages to the
specific vessel and its new operational
requirements, far more can be gained.
Ship owners often approach Wärtsilä
for an individual solution, for example
an upgrade solution on the main engine,
or separately for a proposal of a modified
propeller design. Wärtsilä’s combined
capabilities from engines and propulsion
solutions to system integration and
automation up to its ship design offering
provide a unique opportunity for ship
owners to utilize the company as a
total, integrated solutions partner for
vessel efficiency upgrading projects.
The identification of the savings potential
and initiation of upgrading projects could
be an offspring from the measurements
and evaluations through the Optimisers
platform or from the close collaboration
between ship owner and Wärtsilä under a
services agreement. However, it can also
be initiated separately by initial onboard
audits or desk studies and elaborated in
a joint project that evaluates different
options, selects the optimal package
scope depending on saving targets, actual
situation and available budget, and finally
plans, delivers and implements the selected
scope. Wärtsilä’s professionals from various
functions and competence areas are
brought together into the different phases
of such end-to-end efficiency upgrading
projects, in order to ensure successful
implementation and achievement of the
agreed targets and expected savings.
CONCLUSION
The new offering for SEEMP implementation,
for integrated performance and condition
monitoring and advisory services through
the Optimiser platform, the modular and
flexible scope of agreements that integrate
the advantages of the tools and SEEMP
implementation, and the wide capabilities
to take on end-to-end upgrading project
responsibilities for achieving substantial fuel
savings, makes Wärtsilä a very important
sparring and implementation partner for
ship owners and operators in achieving fuel
cost reductions and efficiency gains.
WÄRTSILÄ TECHNICAL JOURNAL 02.2013
61in detail
Just about 100 years ago, the wastewater
treatment process was invented when our
aqua environment began to deteriorate.
The science, engineering, and regulations
relating to water and wastewater have
evolved slowly but steadily ever since. As
a result, the efforts of municipalities and
land-based industries have led to significant
improvements in water quality, and the
way that it is treated. The marine industry,
meanwhile, continues to explore means
of developing its methods in this area.
So-called ‘grey’ water is the effluent from
living areas, laundries, and galley areas,
while ‘black’ water is the output from toilets.
On land, these waters are collected from our
households and professionally treated in
wastewater treatment works (WWTW). On
a ship, black and grey waters are collected
separately, but often become mingled
during transport, storage and discharge.
Annex IV of IMO's MARPOL Convention,
adopted 40 years ago, set ambitious
standards for ship discharges in MEPC.2(VI).
But there are two shortfalls: 1) grey water
is not regulated, and 2) discharges from
ships have not been monitored.
Grey water pollutes.
On land, nobody expects the grey water
from a restaurant or laundry to be dumped
into a natural water body without treatment.
There are numerous wastewater engineering
text books that explain the scientific basis
Wastewater treatment in the marine industry AUTHOR: Wei Chen , Head of R&D, Wär tsi lä Water Systems Ltd
Over the past 100 years or so, wastewater treatment on land has been successfully developed. However, the marine industry is still working to develop its means of treating wastewater, and Wärtsilä is actively developing the needed technologies for ships.
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for such treatment. Grey water on ships
is just as polluted (Table 1), and Faecal
Coliform concentrations in grey water
exceed the discharge limits of black water
by 100,000 times. Grey water also accounts
for 80 of a ship’s wastewater organic (or
Biochemical Oxygen Demand – BOD5)
loading. Annex IV only covered 20 of
a ship’s wastewater pollution impact.
The technologies are available.
After The U.S. state of Alaska established
that cruise ship discharges were of poor
quality, federal legislation expanding
Alaska’s authority over cruise ship
discharges was swiftly passed in 2000.
Strict rules regarding both grey and black
water were then introduced. This led to
the development of a new generation
of Advanced Wastewater Treatment
(AWT) systems, which have subsequently
exceeded all expectations (Figure 1). This
success has led the USEPA to extend the
stringent grey water requirements to
other US waters (Vessel General Permit,
2008). Most importantly, Alaska has
established the Commercial Passenger
Vessel Environmental Compliance
Program (CPVECP), the one and only
independent monitoring and sampling
regime in the entire global marine
industry. AWTs that were fit for purpose
survived, and those not were weeded out.
Despite being endorsed by the USEPA
as being the Best Available Technology,
and while out-performing WWTWs ashore,
AWT has no clear definition, nor can it
be Type Approved as such. It must do
what it says on the label, year on year,
under the watchful eyes of CPVECP. It
was not easy, but Alaska has provided a
show case of stakeholder commitment
to protect its pristine marine waters.
Wärtsilä has worked with cruise operators
to develop its Membrane Bio Reactors(MBR)
system. MBR works by segregating – or
‘splitting’ – the treatment of black and grey
water on the basis that the latter is less
contaminated and should be treated
separately. The solution has proven to be
extremely successful in meeting all
the Alaska criteria.
The marine industry needs universal regulations.
In addition to Alaska’s clean-up efforts, the
Great Lakes, US waters (EPA Vessel General
Permit, 2013), and inland waterways in
Europe (2012/49/EU) have also regulated
Table 1 – Characteristics of grey waters on ships (USEPA report, 2008)
Faecal Coliform (MPN/100 ml) BOD5 (mg/l)
MEPC.2 (VI) black water discharge limits 200 50
Acoommodation Grey Water 37,000,000 260
Galley Grey Water 29,000,000 1,490
Domestic Wastewater 1,000,000 to 100,000,000 110 to 400
Coliform – Geometric Mean (count/100 ml)
10,000,000
1,000,000
100,000
10,000
100
100
10
1
20
00
20
01
20
02
20
03
20
04
20
05
20
06
20
07
20
08
20
09
20
10
20
11
20
12
20
13
20
14
20
15
20
16
Average BODS (mg/l 02)
600
500
400
300
200
100
0
20
00
20
01
20
02
20
03
20
04
20
05
20
06
20
07
20
08
20
09
20
10
20
11
20
12
20
13
20
14
20
15
20
16
Fig. 1 – Average performance of wastewater treatment plants on ships (Blue bars – cruise ships with AWTS in Alaska; red bar – 32-ship survey in a European port).
WÄRTSILÄ TECHNICAL JOURNAL 02.2013
63in detail
grey water treatment in various shapes
and forms (Table 2), each affecting certain
shipping sectors. There are already four sets
of different type approval specifications, and
more than five different compliant regimes.
This assortment of legislation is a source
of confusion for both vendors and ship
operators. The challenge is further
emphasised by the fact that some ports and
coastal waters ban all discharges, regardless
of the existence or type of AWTS onboard.
Ships often have to hold wastewater in
double bottom tanks, for discharge outside
the restricted waters, at the expense
of extra fuel costs and emissions.
Classification Societies also promote
grey water treatment by offering greener
Class Notations. Almost all type approved
sewage treatment plants claim the capability
to treat grey water, while more and more
ship owners and yards are signing up to
these initiatives. For example, the cruise
industry some years ago voluntarily stopped
discharges of untreated grey water into the
Baltic Sea. The industry saw what’s coming,
and is ready to meet new legislation.
However, the variations in requirements
in different parts of the world can create
confusion regarding equipment selection,
system design, and operations. For instance,
grey water is sometimes ‘treated’ only during
the very last stage of a type approved sewage
treatment system, which results in non-
compliant performance.
At the international level, the lack of grey
water regulations has started to affect other
IMO policies as well. One example of this
is that the positive efforts to accommodate
ballast water tanks for holding grey water
under certain operational conditions, has
been stalled. Attempts to address grey water
pollution along the Northern Sea Route
under the Polar Code have also faltered.
While the needs to control grey water in
the marine industry are just as great as they
are on land, Annex IV unfortunately provides
no provisions for monitoring discharges
from ships. The discharge limits are only
applicable to a type approval test at a testing
facility.
Compared to the detailed specifications
of the CPVECP, i.e. the overboard discharge
sampling point, logbooks, flow measurements,
sampling frequencies and procedures, etc.,
Annex IV lacks such monitoring requirements
totally.
This weakness has been exploited. Type
approved sewage treatment plants that
‘utilise the rich oxygen in the sea water to
Fig. 2 – MBR installations on a new built cruise ship.
Fig. 3 – MBR construction on a new built cruise ship in the ship yard.
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remove pollutants’ by drawing sea water
through them, at as much as more than 40
times the sewage flow, are installed on
hundreds of ships. Dilution is, alas, a poor
means of controlling pollution, and in 2016
constraints will be imposed via MEPC.227(64),
albeit with a lack of enforcement measures.
Even then, the practice will continue to
entertain the notion of marine water
protection without enforcement.
In 2012, one member state surveyed the
performance of sewage treatment plants
onboard 32 ships. It was found that ‘the vast
majority of the equipment did not meet
the existing sewage treatment standards
due to improper use of detergent, a lack
of maintenance, or not following the
operational instructions’ (MEPC 64/23).
Actually, none of the ships satisfied even
the most relaxed MEPC.2(VI) rules adopted
in 1973, and the average results missed the
targets by a long way (Figure 1). This
despite the fact that during the past five
years MEPC.2(VI) has been tightened twice
(MEPC.159(55) and MEPC.227(64)).
The fact that grey water is often
intermingled with black water in the tanks
and pumps makes it difficult to create
effective monitoring. Alaska's CPVECP, on
the other hand, deals with this problem
very well.
The industry welcomes science based regulations
It is not always the case that laws become
more effective when made increasingly
stringent. An Alaskan State Law passed
in 2006, for example, demanded that
cruise ships meet the state’s water quality
standards at the point of discharge. This
made drinking water appear to be toxic
to the ocean. It took an independent
Science Advisory Panel to conclude that
this law should be rolled back since such a
requirement is not relevant, and is anyway
not applied to shore-based discharges.
The process lasted three years, but at
least it reached a science-based closure.
Wärtsilä has achieved world leading status
as a technology provider of future-proofing
black and grey water management systems
for ships. The situation is not, therefore,
that effective treatment is not yet available.
It is the will to ensure that this treatment is
carried out that appears to be lacking, and
the fact that 32 ships exceeded the IMO's
discharge limits by a factor of 1000 gives
cause for concern. Regarding the removal
of nutrients from ship sewage discharges,
the Baltic Sea has been designated by the
International Maritime Organisation (IMO)
as being a Particularly Sensitive Sea Area
under its MARPOL Annex IV. However,
passenger ships have contributed just 0.035
of the Baltic Sea’s nitrogen load,and even this
minute contribution hasbeen diverted to
port reception facilities, thanks to the cruise
industry’s proactive stance since 2009.
Nevertheless, this effort has failed to win
the hearts and minds of the Baltic rim
countries. In 2012, a proposal was adopted
to make the discharge levels of nutrients
from passenger ships more stringent than
equivalent standards ashore. This was branded
by industry groups as being ‘a sad day’
but there were, nevertheless, a number of
member states wanting to implement these
standards also for the Mediterranean, and
other sea areas. By the way, the Mediterranean
Sea is defined as nutrient-poor water by
the European Environmental Agency.
Had there been an independent Science
Advisory Panel or a monitoring regime,
this confusion could have been avoided.
Fortunately, more regulators, at least those
ashore, have recognised that environmental
initiatives can have an adverse impact by
consuming natural resources, and incurring
emissions that need to be justified by the
tangible benefits they may bring. Having
science based rules is no longer a question
of the more stringent the better. Since it takes
more than aspirations to find a balance, the
rules can and should be science based,
practicable, and sustainable.
When it comes to black and grey water
pollution from ships, maybe it is time for
the marine community to do something
simple, and to do it right, such as regulating
both black and grey water - and having such
regulations enforced.
Fig. 4 – MBR retrofitted in-situ while the ship was trading.
WÄRTSILÄ TECHNICAL JOURNAL 02.2013
65in detail
Table 2 – Key regulations on black and grey water discharges from the ships.
Standards
IMO MARPL Annex IV EU USA Alaska
MEPC. 2 (VI)
MEPC. 159 (55)
MEPC. 227 (64)
2012 (Inland Water ways)
USC G33CFR 159
Type II MSD
EPAVessel
General Permit
USC G33CFR159Subpart E
GP No. 2009DB0026
Continuous(Underway)
Water Quality
Standards (AWQS)
Enter into force 2003 2010 2016 2013 1975 2013 2000 2009–15 2006–13
Applicable streams
Black Black Black Black & GreyBlack
(Grey in Great Lakes)
Grey Black & Grey
Type Approval IMO IMO IMO EU USCG N/A N/A
Applicable ships AII AII AII AII AII100–499
>500Passenger
> 500Passenger
> 250
F. Coliform (/100 ml)
200 100 100 200 20 20 14 14
TSS (mg/l) 100 35 35Qi/Qe 150 30 30 150 150
BOD (mg/l) 50 25 25Qi/Qe 25 30 30 30 30
COD (mg/l) 125 125Qi/Qe 125
TOC (mg/l) 45
pH 6~8.5 6~8.5 6.5~9 6.5~9 6.5~8.5 6.5~8.5
Chlorine (mg/l) 0.5 0.5 0.01 0.01 0.01 0.01
TN (mgN/l), Spe-cial Area, passenger > 12
20 Qi/Qe or 70%
TP (mgP/l), Special Area, passenger > 12
1 Qi/Qe or 80%
Ammonia (mgN/l) 28 (130) 1
Dis. Copper ( g/l) 87 (130) 3.1
Dis. Nickel ( g/l) 43 (43) 8.2
Dis. Zinc ( g/l) 360 (360) 81
Wärtsilä Water Systems Ltd is an innovative, market
leading company providing conventional and advanced wastewater
treatment systems in response to environmental needs and
marine legislations. During the past 40 years, the company
has provided over 8000 installations across all ship sectors.
Building on the success of its advanced Membrane BioReactor
technology, the company has developed a unique wastewater
management system that allows future proofing compliant
operation at low operational costs and with minimum skill
requirements. This system has been successfully implemented
on multiple cruise ships, many of them sailing in Alaska waters.
IMPROVING LIFECYCLE EFFICIENCY BY LOOKING AT THE BIG PICTURE
In the current market situation, companies are focusing on improving efficiency and reducing
costs. Wärtsilä improves the lifecycle of ship and power plant installations by looking into three
areas. Preventing the unexpected helps guarantee performance and manage risk. Environmental
efficiency optimises environmental performance. And performance optimisation helps improve
business efficiency and reduce operational expenses. Please read more about improving lifecycle
efficiency at wartsila.com/services.
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The information in this magazine contains, or may be deemed to contain “forward-looking statements”. These statements might relate to future events or our future financial performance, including, but not limited to, strategic plans, potential growth, planned operational changes, expected capital expenditures, future cash sources and requirements, liquidity and cost savings that involve known and unknown risks, uncertainties and other factors that may cause Wärtsilä Corporation’s or its businesses’ actual results, levels of activity, performance or achievements to be materially different from those expressed or implied by any forward-looking statements. In some cases, such forward-looking statements can be identified by terminology such as “may,” “will,” “could,” “would,” “should,” “expect,” “plan,” “anticipate,” “intend,” “believe,” “estimate,” “predict,” “potential,” or “continue,” or the negative of those terms or other comparable terminology. By their nature, forward-looking statements involve risks and uncertainties because they relate to events and depend on circumstances that may or may not occur in the future. Future results may vary from the results expressed in, or implied by, the following forward-looking statements, possibly to a material degree. All forward-looking statements made in this publication are based only on information presently available in relation to the articles contained in this magazine and may not be current any longer and Wärtsilä Corporation assumes no obligation to update any forward-looking statements. Nothing in this publication constitutes investment advice and this publication shall not constitute an offer to sell or the solicitation of an offer to buy any securities or otherwise to engage in any investment activity.
