Group Assignment[1]

School of Control Systems and Electrical Engineering

Department of Electrical Services Engineering

Higher Certificate in Electrical Services Engineering

Programme Code DT083/5

2010-2011

Student Names: Rory Conlon; Aidan Conroy; Paul Derwin; Mark Stewart

Student No.: D-07114364; D-07114348; D-07114349; D-05110728

Class Group: DT083/5

Date: 23.11.2010

DECLARATION We declare that all material contained in this project is our own work, and has not

been submitted for any academic assessment other than part fulfillment of the

assessment procedures for the programme “DT083 – Ordinary Degree in

Electrical Services Engineering”. Supporting additional material is fully and

specifically acknowledged wherever adapted from other sources.

Name Signed Date

Rory Conlon

Aidan Conroy

Paul Derwin

Mark Stewart

Student Names: Rory Conlon; Aidan Conroy; Paul Derwin; Mark Stewart

Student Nos.: D-07114364; D-07114348; D-07114349; D-05110728

Course Code: DT083

Year: 5

III

Table of Contents

INTRODUCTION ........................................................................................................................................ 1

AIM................................................................................................................................................................ 1

METHODOLOGY....................................................................................................................................... 1

POOL HEATING CRITERIA.................................................................................................................... 3

SOLAR HEATING ........................................................................................................................................... 3

SOLAR POWER ............................................................................................................................................. 3

SOLAR DATA ................................................................................................................................................ 4

WIND POWER ............................................................................................................................................... 4

BEST PRACTICE IN RELATION TO SITING ........................................................................................................... 5

LOCAL REQUIREMENTS .................................................................................................................................. 5

WIND SPEED ................................................................................................................................................ 5

ELEVATION INFLUENCES ................................................................................................................................ 6

ENERGY OUTPUT .......................................................................................................................................... 6

WIND DATA .................................................................................................................................................. 7

TURBINE COSTS ........................................................................................................................................... 7

HEAT INPUT CALCULATIONS .............................................................................................................. 8

HEAT STORAGE ............................................................................................................................................ 9

HEAT LOSSES............................................................................................................................................. 10

CALCULATIONS ........................................................................................................................................... 11

TURBINE SELECTION............................................................................................................................ 15

COSTS......................................................................................................................................................... 16

SCALE OF PROJECT............................................................................................................................... 17

REFERENCES & ACKNOWLEDGEMENTS ....................................................................................... 19

Student Names: Rory Conlon, Aidan Conroy, Paul Derwin, Mark Stewart

Student Nos: D-07114364; D-07114348; D-07114349; D-05110728

Page - 1 -

Introduction This assignment investigates a design for maintaining the temperature of a

swimming pool incorporating the collection and storage of sustainable energy

with a view to reducing the dependency on fossil fuels. Comparisons will be

drawn between the proposed design, and the projected cost of operating a

traditionally designed swimming pool.

Aim To assess the possibility of extracting the maximum benefits of both solar and

wind energy in an application where there is a requirement for almost constant

heat input, and to compare the proposed design against traditional designs.

Methodology The data assessed in this assignment includes;

1. Energy required to maintain or increase the temperature of the swimming

pool water.

2. Typical energy available from solar radiation and wind power and the

projected consistency of availability.

The compilation of the above data will provide the basis for calculating the

energy input requirement and the most effective energy harvesting combination

to provide this energy in a consistent manner. Contingency for periods of excess

or shortage will be catered for by the inclusion of a thermal store as part of the

structure.


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Pool Design Criteria

In the majority of cases, and for practical reasons such as access, structural

engineering and common sense, swimming pools are situated on or close to the

ground level of a building. In effect, the pool itself is almost always below ground

level, which also reduces thermal losses to some extent because fabric losses

through the floor of a building are generally lower than through the external walls.

Fabric loss calculations are directly proportional to the differential temperature

across the building element, i.e. the difference in temperature between inside

and outside the building. When calculating the potential heat loss through an

external wall of a residential building for example, Building Services Engineers

generally base their calculations on maintaining a target internal air temperature

of 21oC with a worst case outside air temperature of -2oC, resulting in a

differential temperature of 23oC or more correctly 23 Kelvin. Heat losses through

the floor slab are never as significant because the soil temperature rarely

fluctuates to the same extent as the air temperature. In general, the soil

temperature in Ireland fluctuates between 10oC and 16oC for a depth of up to 3

metres, making below ground level an ideal location for the pool and also for a

thermal store. In addition to the pool structure itself, the large volume of water

involved will also act as a thermal store. The criteria for construction will feature

the following;

1. Method of utilising harnessed energy directly for increasing and

maintaining the pool water temperature.

2. Method of storing excess harnessed energy.

3. Method of releasing harnessed energy.

4. Method of re-directing excess energy to supply ancillary services.


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Pool Heating Criteria The successful design for a swimming pool which will relies on solar and wind

power as primary sources of energy will depend largely on the accuracy of the

data used to determine the quantity and type of collectors used for the purpose.

The levels of solar radiation in Ireland are relatively constant regardless of

location, but the wind speed can vary significantly even with minor alterations in

altitude or position in relation to obstructions. For the purposes of this proposal,

the solar radiation and wind speed data is the average values recorded by the

MET Eireann weather station at Dublin Airport.

Solar Heating

Because of the relatively low temperature and high volume of water required in a

swimming pool, the flat panel solar collector has been selected as the most

appropriate for this application. The efficiency of solar collectors vary slightly from

one manufacturer to the next, the most efficient being approximately 19%.

The basis for calculating the quantity of Solar Panels required for the purpose, is

based on various manufacturers data coupled with the recorded data at Dublin

Airport.

Solar Power

The solar radiation data recorded by MET Eireann at Dublin Airport is provided in

the format of Global Radiation in units of Joules/cm2. The typical output for a 2m2

solar panel at an angle of 30 degrees elevation provides 1200kWh of energy per

annum. To calculate the anticipated output of a panel for each month of the year,

we divided the total output by the total radiation to provide the output per quantity

of radiation, as follows;

Total annual average Solar Radiation = 332kJ/cm2

Total annual output of 2m2 Solar Panel = 1200kWh

Panel Output = 1200/332 = 3.62kWh for each kJ/cm2 of solar radiation


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Solar Data

Using the average monthly global radiation value provided by MET Eireann, we

can calculate the panel output on a monthly basis as demonstrated on the table

below.

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Solar Radiation J/cm

2

7229 11848 24282 36901 46566 50216 52826 40798 29855 17554 8467 5137

kWh per panel

26.15 42.87 87.85 133.50 168.47 181.68 191.12 147.60 108.01 63.51 30.63 18.59

The output values will provide a guideline for the number of panels required to

heat the swimming pool for each month of the year. It is obvious from the above

that the output during the winter months will be much less than during the

summer. To maximise the efficiency of the system, the expectation is that the

quantity of panels required for the summer months will be sufficient, with the

shortfall of energy made up by the wind turbines during the winter months.

Wind Power

In most wind power applications, it is necessary to provide a working system with

complex and expensive controls to allow connection to the grid. In this

application, no such controls will be necessary as all of the power harvested will

be used directly at source. A simple direct connection from the generator to the

load will be sufficient. Unfortunately, the data provided by most manufacturers

and suppliers of this equipment is aimed at the micro generation or wind farm

market and includes for all controls and equipment for grid connection, and as

such, no correction factor has been made to address this issue.

The most important factor when attempting to harness wind power is consistent

availability of useful wind energy. The best sites for turbines rarely coincide with

the best sites for swimming pools, however, there is a relatively consistent supply

of wind power in almost all parts of the country, with increased benefits in most

coastal regions. The focus of attention is on the adequacy of output from the

Wind Turbine under average conditions rather than the possibility of planning

restrictions or any other practicalities.


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Best practice in relation to Siting

Optimal siting has to take account of:

• Annual average wind speeds, (generally between 3 and 8m/s)

• Ground conditions necessary for structural stability of turbines and

associated infrastructure

• Proximity to dwellings and settlements

• Soil Stability - Sites located on deep peat are unsuited because of their

instability

• Location and Prevailing Winds

Wind direction may vary significantly, but there are prevailing directions that you

should study. The turbine should face the prevailing winds, and should catch the

turbine without obstruction. Wind speeds across the country can be modeled

using the Weibull Distribution. This statistical tool will tell us how often winds of

different speeds will be seen at a location with a certain average (mean) wind

speed. Knowing this will help us choose a wind turbine with optimal cut-in-speed

(the wind at which the turbine starts to generate usable power), and the cut-out-

speed (the speed at which the turbine hits the limit of its alternator and can no

longer put out increased power output with further increases in wind speed).

Local Requirements

Take into account local requirements when planning a wind system location.

They vary and may include environmental assessments, studies on the impact

on the wildlife or communications (local air traffic, for instance).

The height of a wind turbine tower is an important element to consider and

should take into account the height of the surrounding obstructions. The height of

the tower should place the bottom of the turbine blades at least 10 meters/30 feet

above the top of any obstacle within 100 meters of the tower.

Wind Speed

Electricity output is proportional to the wind speed cubed. Thus a small difference

in the average wind speed has a big effect on electrical output. A 2 MW wind

turbine located on a site, which has an annual wind speed of 6m/s (metres per


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second) will produce less than half as much energy as the same machine on a

site where the annual wind speed is 8m/s. Sites with a mean wind speed above

7.5m/s are favoured.

Elevation Influences

Wind speed is not the sole influence. An allowance has to be made for potential

higher costs required to create and manage wind turbines at higher altitudes. At

low wind speeds, a turbine does not supply any electricity. From 3-4m/s, the

turbine starts producing power and from about 12m/s, the maximum capacity is

supplied. At wind speeds above 25m/s, the turbine is stopped to avoid

overloading. At a good location, an average turbine annually supplies an

electricity output of at least 850 kilowatt hours per square meter of rotor surface.

The wind at a particular location can be influenced by a number of factors such

as obstruction by buildings or trees, the nature of the terrain and deflection by

nearby mountains or hills. For example, the rather low frequency of southerly

winds at Dublin Airport is due to the sheltering effect of the mountains to the

south. The prevailing wind direction is between south and west. Annual wind

speeds range from 7 M.P.H. in parts of south Leinster to over 18 M.P.H. in the

extreme north. But the north and west coasts of Ireland are two of the windiest

areas in Europe and have considerable potential for the generation of wind

energy.

Energy Output

To Calculate kWh generated by Wind Turbine, the average annual output of

850kWh per m2 rotor surface at an average wind speed of 8m/s is used as a

guideline. From wind speed data provided by MET Eireann, we can calculate the

monthly output per m2 of rotor surface and identify a suitable turbine, or array of

turbines to provide the energy required. In order to calculate the surface area of

the wind turbines required, it is necessary to calculate the output in Watts per m2

of rotor surface area for each month of the year. The average wind speeds

provided by MET Eireann will be used to evaluate the anticipated output per

month.


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Optimal Wind Speed = 8 m/s

Total annual output per m2 of rotor surface at 8m/s = 850kWh per annum

Where Wind Speed = Vw the ouput is proportional to Vw3

Total kWh Output per m2 at 8m/s = 850

Output is proportional to Wind Speed3 therefore;

Output per m2 rotor area = kWh/ Vw3 = 850/83 = 1.66kWh/m/s

Average Daily Output per m/s = 1.66kWh/365 = 45.48 Wh per m2 per m/s

Wind Data


Mean Monthly Wind Speed m/s

6.28 6.02 5.97 4.99 4.48 4.12 4.17 4.58 5.09 5.56 6.07 5.09

kWh per Day

1.12 0.99 0.97 0.57 0.41 0.32 0.33 0.32 0.44 0.60 0.78 1.02

Total kWh per m

2

34.86 27.77 29.96 16.95 12.64 9.51 10.20 9.83 13.53 18.63 23.40 31.54

From the above calculations, it can be demonstrated that the sum total of all

monthly output per m2 rotor area = 257.5 kWh per annum, which is considerably

less than the ideal return of 850kWh.

Turbine Costs

The total costs for installing a commercial scale wind turbine will depend on the

size of the turbine, when the turbine purchase agreement is executed,

construction contracts, the type of machine, the location of the project, and other

factors. Cost components for the project include wind resource assessment and

site analysis expenses, the price and freight of the turbine and tower, protection,

metering equipment, insurance, operations, warranty, maintenance and repair,

legal and consultation fees. For example, the cost in 2007 for a commercial scale

2MW wind turbine was approximately €2 million.


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Heat Input Calculations The heat required to maintain the temperature of a swimming pool is made up

from a combination of fabric losses and infiltration losses. In addition, the pool

temperature will occasionally drop to below the recommended minimum

temperature and will need to be re-heated. The heat input required to address

the normal running losses can be approximated by calculating the fabric and

infiltration losses at a specific outside air temperature and providing a sufficient

source of heat to counteract the losses. The energy required to increase the

temperature of the water is determined in a similar fashion but because of the

large volume of water involved, there is a compromise to be reached between

energy input and reheat time. The intention of this proposal is to address normal

running losses only and to provide design calculations to maintain the pool water

temperature during average conditions. During periods of over supply, the heat

generated will be applied to the thermal store up to a pre-determined maximum

temperature. The maximum temperature can be adjusted to minimise or

maximise the buffer capacity of the thermal store for varying weather conditions,

for example, as the outside air temperature decreases, the thermal store

maximum temperature can be increased to compensate for the possibility of

additional losses. Any energy produced over and above the maximum value can

be re-directed to heat exchangers which can be used to heat the showers or

warm the ambient air in the pool area.


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Heat Storage

As mentioned above, due to the volume of water involved, the pool itself will

retain a large quantity of heat. However, water also loses heat relatively quickly

and so an alternative form of heat storage has been incorporated into the design.

The pool construction itself consists of a sizeable volume of concrete, which has

the ability to conduct and retain heat. The principle of operation of the proposed

system is similar to that of the electric storage heater in that the heat from both

the solar panels and the wind turbines is applied to the concrete form

surrounding the pool. The concrete pool structure is insulated from the external

structure of the building to eliminate or minimise any heat losses through thermal

bridging and reduce fabric losses to a minimum. The absorbed heat flows from

the concrete to the water by conduction, thereby raising the temperature of the

water. There are a number of advantages to this form of heating as follows;

1. Most pool heating systems use natural gas or oil fired heating via heat

exchangers requiring a high primary temperature and large volume

secondary flow rate. Both conventional and condensing gas boilers

operate less efficiently at higher temperatures. In the proposed system,

the pool water is heated directly over a large surface area (i.e. the internal

surface area of the pool), therefore, even using conventional heating

systems, the primary temperature does not need to be much greater than

the secondary temperature, which and would therefore increase efficiency,

regardless of heat source.

2. Traditional systems allow the pool water to stratify when the circulation

pumps are switched off. It is then necessary to run the pumps for a

number of hours before occupation to allow the pool to reach a uniform

temperature. The proposed system heats the pool water from the

surrounding surface area causing convection currents to naturally circulate

the water thereby preventing stratification and eliminating cold spots. The

circulation pumps need only be operated for filtration purposes.


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Heat Losses

Maintaining the temperature of the pool water is critical for both user comfort and

the economical operation of the pool. The desired pool temperature is a matter of

choice but generally falls in the range of 27oC to 30oC. The lower end is generally

recommended for competitive swimming and the upper end for the leisure

market, but in any case, the heat losses incurred will be similar and must be

minimised.

In order to maintain the desired temperature of any occupied space, it is

necessary to take actions to prevent or minimise heat losses. In addition to fabric

and infiltration losses, swimming pools also have specific issues which need to

be addressed. The fabric losses can be addressed by insulating the external

structure of the pool using high density foam insulation. When the pool has

reached operating temperature, there is a tendency for the warm water to

evaporate. When the pool is dormant, these losses can be minimised by applying

a proprietary pool cover, but during occupation, the effects are magnified due to

the constant agitation of the water. A method of reducing this loss during periods

of occupation is to increase the room air temperature to a few degrees above the

pool temperature. Heat energy tends to travel from warm to cold, so if the air

temperature is higher than the pool temperature, the losses due to evaporation

will be minimised.


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Calculations

Using an Olympic size pool as a template, the following calculations estimate the

heat input required based on the volume of the pool;

Pool Dimensions = 50m x 20m x 2m = 2000m3 = 2,000,000 litres.

Energy Required to raise temperature of water = Q

Q = MC∆T where;

M = Mass of Water in kg (1 litre = 1kg)

C = Specific Heat Capacity of Water = 4.2kJ/kg

∆T = Differential Temperature

To raise the temperature of the water by one degree in one second, the heat

input required is;

Q = 2,000,000 x 4.2 x 1 = 8,400,000kW

If the increase in temperature takes place over a period of 24 hours, the energy

input required = 8,400,000/(3600x24) = 97.22kW.

In other words, if the swimming pool heat loss equates to one degree per day,

the constant energy input required to compensate for this loss equates to

97.22kW.

Assuming that the maximum pool temperature is 30oC, and that the heat is

applied to the thermal store, it will be necessary to increase the temperature of

the thermal store to above the pool temperature. The greater the differential

temperature, the greater the flow of heat from one mass to the other. Assuming

that all heat applied to the concrete thermal store will travel to the pool, if the

same energy input calculated above is applied to the concrete, the pool

temperature will be maintained.

For a concrete structure of the following dimensions;

50m x 20m x 1.2m = 1200m3

The density of concrete = 2300kg/m3

The Mass of the concrete = 1200 x 2300 = 2,760,000kg


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The increase in temperature of the concrete can be calculated as follows;

Q = MC∆T where;

Q = 8,400,000kW

M = Mass of Concrete in kg = 2,760,000 kg

C = Specific Heat Capacity of Concrete = 0.84kJ/kg

∆T = Differential Temperature

Therefore ∆T = Q/MC = 8,400,000/(2,760,000 x 0.84) = 3.62oC

Assuming that the fabric losses around the thermal store are negligible, for each

degree lost by the swimming pool, the concrete temperature requires a

temperature increase of 3.62 oC to restore the pool temperature to the target

level. Because the target temperature of the thermal store is in excess of the

target pool temperature, the differential temperature between the surfaces will

allow the heat to flow from the store to the pool, thereby maintaining the pool

water temperature as required.

The heat applied to the thermal store is approximately 0.5 metre below the

bottom surface of the pool.

Thermal Conductivity of Concrete = 2.2 W/mK

The Thermal Resistance of Concrete Thermal Store = 0.5/2.2 = 0.23 m2K/W

The U-value of the concrete is therefore = 1/0.23 = 4.45W/m2

The total instantaneous transfer of heat energy from the pool floor to the water

per degree of differential temperature;

Ф = U x A x (T2 – T1) = 4.4 x 20 x 50 = 4.45 kW

If the heat input to the thermal store = 97.22kW, the required temperature at a

distance of 0.5 metres below the pool can be calculated as follows;

Target Pool Temperature + (97.22/4.45) oC = (30 + 22) = 52oC

This differential temperature will allow adequate heat flow from thermal store to

pool and is also within the normal operating range of the solar panels.


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By combining the monthly data, the output data for solar panels and wind

turbines, and the energy data calculated to raise the temperature of the pool, we

can quantify the number of solar panels or the surface rotor area of wind turbine

required to provide this energy. The following table demonstrates these

calculations effectively.

L W D Vol (m3) kg/m3 C

(kJ/kg)

Heat Input

Required Totals

Pool Water Data 50.00 20.00 2.00 2000.00 1000.00 4.20 8400000 kW

Per Hour 2333.33 kW

Per 24 Hrs 97.22 kW

Concrete Data 50.00 20.00 1.20 1200.00 2300.00 0.84 2318400 kW

Per Hour 644.00 kW

Per 24 Hrs 26.83 kW

Temp Data Target Recovery

Pool 30 24 Hrs

Concrete 33.62 24 Hrs

Heat Input Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Avg Concrete Temp 30 30 30 30 30 30 30 30 30 30 30 30

Differential Temp 3.62 3.62 3.62 3.62 3.62 3.62 3.62 3.62 3.62 3.62 3.62 3.62

Avg Pool Temp 29 29 29 29 29 29 29 29 29 29 29 29

Differential Temp 1 1 1 1 1 1 1 1 1 1 1 1

Required Input 97 97 97 97 97 97 97 97 97 97 97 97

kWh per Day 2331 2331 2331 2331 2331 2331 2331 2331 2331 2331 2331 2331

Energy Required 72270 65276 72270 69938 72270 69938 72270 72270 72270 72270 69938 72270

Monthly Outputs Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Wind Turbine kWh/m

2 34.86 27.77 29.96 16.95 12.64 9.51 10.20 9.83 13.53 18.63 23.40 31.54

Solar Panels kWh/Panel 26.15 42.87 87.85 133.50 168.47 181.68 191.12 147.60 108.01 63.51 30.63 18.59

Quantity Required

Turbine m2 2073.26 2350.59 2411.90 4124.95 5717.11 7352.99 7084.01 7352.99 5340.28 3879.97 2988.57 2291.33

Solar Panels 2763.25 1522.82 822.65 523.87 428.97 384.96 378.14 489.62 669.08 1137.95 2283.12 3888.56

Turbine Solar

Quantities Used 2200 400

Proj Wind Energy 76687 61094 65920 37301 27810 20925 22444 21623 29772 40978 51484 69389

Proj Solar Energy 10462 17146 35140 53402 67389 72671 76448 59041 43205 25404 12253 7434

Proj Comb Output 89349 78640 101060 90703 95199 93596 98892 80664 72978 66381 63738 76823

It can be seen from the data above, that on average, the maximum requirement

for wind energy coincides with the minimum requirement for solar power (ie from

April to September).

Using this data, we can show that a combination of solar panels and wind

turbines can provide a steady form of energy supply, capable of maintaining the

temperature of the pool for ten months of the year, with a slight shortfall in


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October and November. Because the calculations are based on averages, it is

likely that the values for wind and solar power would vary on a daily basis, and

the thermal store would be expected to provide a buffer for the periods in

between, resulting in a relatively constant heat source.

Collector Outputs

0

10000

20000

30000

40000

50000

60000

70000

80000

90000


Month

kW

h Proj Wind Energy

Proj Solar Energy

Output vs Required

0

20000

40000

60000

80000

100000

120000


Month

kW

h Energy Required

Proj Comb Output


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Turbine Selection Using manufacturers data supplied by Unison, and the average wind speed provided by

MET Eireann, it is possible to plot the anticipated output for each of the turbines.

The projected output from the U50 turbine follows the projected Wind Energy

Requirement most closely.

Wind Energy Required vs U50 Output

0

10000

20000

30000

40000

50000

60000

70000

80000

90000

100000


Month

kW

h Proj Wind Energy

U50


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Costs The overall cost of the project would be difficult to accurately assess, particularly

when measured against the current cost of fossil fuels. In the first instance,

providing a single wind turbine would not be feasible, as the planning restrictions,

margin for error and capital cost would be too great. The budget cost for supply

of a large scale wind turbine is currently in the region of €1,000 per kW output.

With a maximum output in the region of 700kW, the cost of a U50 turbine would

be approximately €700,000.

The cost of Solar Panels has reduced over the past number of years, with flat

plate collectors currently retailing at approximately €400. On a large scale

project, the cost would probably be substantially discounted, however, based on

€400 per unit, the total cost for supply only would be approximately €160,000.

Given that any alternative heating system would require installation and controls,

the value of the installed system can be measured by comparing the capital cost

of the energy saving equipment against the projected cost of fuel. The Energy

Comparison data provided by SEAI lists the delivered cost per kWh of various

fuels. The cleanest and most popular for this type of application is piped Natural

Gas, which costs 2.49 cent per kWh at the cheapest tariff (ie the largest

consumer). The most sustainable alternative is wood chips at a price of 3.41 cent

per kWh. Predictably, the cheapest form of fuel is coal at 0.71cent per kWh.

Based on the energy requirements calculated above, the total annual energy

requirement is estimated at 853.25 MWh. The following table estimates the

equivalent cost of energy from these sources at 95% combustion efficiency.

Fuel Type Cost/kWh kWh Required Total Cost

Natural Gas €0.0249 €22,322 Wood Chips €0.0341 €30,570

Coal €0.0071

896,470

€6,365

Fuel Type Annual Cost Capital Cost Payback Period (yrs)

Natural Gas €22,322 38 Wood Chips €30,570 28

Coal €6,365

€860,000

135


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Scale of Project

When viewed to scale, it is obvious that such a development will be subject to

scrutiny in the planning department. Selecting a greater number of smaller wind

turbines may be a more effective solution from the feasibility point of view,

however, it probably be a cause for concern from any nearby residents as

regards operating noise.

The solar panels fit in quite well with the overall dimension of the pool building

and are unobtrusive in both appearance and performance. The total floor area

required to accommodate the solar panels is based on the pool dimension with

an additional 2,300 square meters of space for viewing galleries, showering &

changing areas, administration and general public areas.

Pool Building

including 400 x

2m2 Solar Panels

Equivalent Size of

Pool

Equivalent Size of

Wind U-50 Turbine


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Conclusion

The average climatic conditions experienced in Ireland provides a relatively

constant source of “free energy”. Harvesting and utilising this energy is a

challenge which must be met at some point in the not too distant future. The

proposal put forward by this team demonstrates that while this “free energy “ can

dramatically reduce the dependency on fossil fuels in an application which

requires a consistently large energy input, there are a number of limiting factors

to be considered;

1. There is still a need for a dependable alternative source of energy as a

backup.

2. The site location will need careful consideration for a number of reasons

including;

a. to maximise the efficiency of the selected systems

b. to comply with planning restrictions

3. A feasibility study detailing the cost of both installation and maintenance of

the systems would not make financial sense when balanced against the

current cost of energy from fossil fuels.

The proposal does demonstrate the practicalities of harvesting and storing

energy, and with improved technologies in the area of energy storage, there is

the potential for realistic and cost effective solutions for the future. The

possibilities for such solutions are unlimited but are most effective where there is

an almost constant demand for controllable heat energy, such as high density

living accommodation, hospitals, hotels, office buildings etc. The key to the

success of such solutions lies in the ability to economically store the thermal

energy and the ability to deliver the stored heat in a controllable and efficient

manner.


Student Nos: D-07114364; D-07114348; D-07114349; D-05110728

Page - 19 -

References & Acknowledgements

SEAI (Sustainable Energy Authority of Ireland)

MET Eireann

Cement Roadstone Holdings

Unison Wind Turbines

www.irishpvandwind.ie

www.lightbucket.com

www.brighthub.com

www.weibull.com

Date post:	13-Aug-2015
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