Liquid Air in the energy and transport systems:

Opportunities for industry and innovation

“It's not right that one generation should use up most of the world's resources

during their lifetime. So, the more we can do to alleviate that the better.”

Peter Dearman

Supply

• Non-reliance of fossil fuels

• Increased proportion of renewables

• Use of distributed resources

• Importance of providing a resilient power supply

• Natural events or deliberate attack

Three core objectives for government or business: Security of Supply, Economy, Sustainability

Demand

• Ever increasing demand from digital society

• Increasing peak demands

• Trend towards summer peaking (cooling)

• Incorporation of transport

• Smart grid

? Energy challenges

What sits in the middle?

The four tools for system balancing:

Flexible

generation

Storage (absorbs

and rejects power)

Inter-connectors (and new

T & D )

Demand

side response

Energy Storage: Only one which can absorb wrong time energy for use in static and transport application, displacing fossil fuels.

Energy Storage - challenges: • One size doesn’t fit all – need a

portfolio of solutions with different characteristic

• Pumped hydro – geographically or geologically constrained

• Batteries – cost, lifetime, scalability

• Key characteristics of new

solutions; • capex • scaleable/flexible • durability/lifetime • safe

Energy challenges

University of Birmingham University of Brighton University of Leeds Imperial College London Queen Mary, London University of Strathclyde Dearman Engine Company E4tech Electricity Storage Network

Some of those involved

Grant Thornton Highview Power Storage IMechE National Grid Messer Group Pöyry Productiv Ricardo UK Spiritus Consulting

Round tables: • Transport • Grid • Global supply chain • Germany • Scotland

Questions we asked

• A single gasometer-style tank of liquid air could make

good the loss of 5GW of wind power for three hours.

• Smaller systems can provide zero-emission back-up and reserve services to replace diesel gensets.

• Reduce diesel consumption in buses or freight vehicles by

25% using a liquid air Dearman engine / diesel hybrid.

• Cut emissions from refrigeration on food lorries by 80%. • It also raises the possibility of zero-emission liquid air city

cars or vehicles at a fraction of current fuel costs and with lower lifecycle vehicle emissions than electric or hydrogen vehicles.

Some conclusions

710lts air 1lt Lair

stored at atmospheric pressure

710lts air + lots of cold

Waste / off-peak electricity

Power on-demand

-196 C

Harness low grade waste heat

The basic principle

Cryogenic liquids are widely used in a variety of industrial applications; but their use as an energy vector is only just emerging. • Air is abundant and available without cost;

• Existing infrastructure to support early adoption; well

understood and supported by internationally recognised codes; • Mature supply chain/components with proven life (25 year+),

performance, O&M cost, etc;

• Storage is at low pressure, resulting in low cost, above ground, safe bulk tanks;

• There is no fuel combustion risk;

• No geological/geographical constraints; flexible and scaleable;

• 7x more energy dense (by volume) than compressed air;

• Synergy with other industrial processes, including use of waste heat and provision of cold.

Cryogens are already safely transported on our roads. Driver operated filling systems for LN2 refrigeration systems already in place.

Existing infrastructure

Reciprocator engine using liquid air as the ‘fuel’. Large-scale, long duration energy storage system using liquid air as the energy storage.

waste heat

Highview Power Storage The Dearman Engine Company

A full range of applications

• Developing a novel, patented, zero emission engine that runs on liquid air or liquid nitrogen.

• The engine is likely to deliver on cost, carbon/emissions reduction and be low maintenance.

• A key application is as a high efficiency, low grade rejected heat recovery system.

• Working with Ricardo and academic partners.

• On track to deliver a test engine during Q4 2013; and, working with MIRA, a “proof of concept” vehicle(s)/integration mule(s) by Q2 2014 to prepare for full application specific field trials as early as 2015.

• Fuelling infrastructure; vehicle filling systems is mature.

Dearman Engine

Process • Operates by boiling liquid air to produce high

pressure gas that can be used to do work. Inventive Step • Boiling takes place inside cylinder through

direct contact heat exchange with a heat exchange fluid – patent granted.

Return Stroke Warm heat exchange fluid (HEF) enters the cylinder.

Top Dead Centre Cryogenic liquid is injected directly into the cylinder.

Heat transfer with the HEF causes rapid vaporisation

and pressure rise.

Power Stroke The vaporised cryogenic

liquid expands pushing the piston down. Direct contact

heat transfer continues allowing near isothermal

expansion.

Bottom Dead Centre The exhaust mixture

leaves the cylinder. The gas is returned to the

atmosphere and the HEF is re-heated and re-used.

No high pressure heat exchangers Rapid expansion High pressurisation rates

Near isothermal (constant temperature) expansion

Non combustive

1. 2. 3. 4.

Dearman Engine - technology

0

0.05

0.1

0.15

0.2

0.25

0 500 1000 1500 2000 2500 3000

Spec

ific

wor

k ex

pans

ion

/ kW

h.kg

-1

Maximum cylinder pressure / bar

Adiabatic Isothermal minus pump work

Benefits of the approach in terms of efficiency can be seen with reference to specific work available from vaporising and expanding 1 kg of liquid nitrogen.

Importance of isothermal expansion

Importance of isochoric pressurisation

Benefits of invention

Dearman Engine - technology

A 300 kW truck diesel engine might reject ~200 kW heat to coolant.

~100oC engine coolant TH = 373 K

~20oC sink temperature (ambient) TL = 293 K

Conventional heat recovery systems have low maximum potential to produce work:

Best possible yield

%21=

~100oC engine coolant TH = 373 K

Dearman Engine as heat recovery system has much higher maximum potential to produce work:

-196oC sink temperature (LN2)

TL = 77 K

%79=Much lower sink temperature

Best possible yield

V

High efficiency low grade waste heat recovery system

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0 500 1000 1500 2000 2500 3000

Spec

ific

wor

k / k

Wh.

kg-1

Peak pressure / bar

Heat from Exhaust @200'C Coolant TemperatureAmbient Adiabatic Ambient Isothermal

Dearman Engine - technology

Other technologies

Ability to use a low grade or ambient source of heat: Able to utilise heat <100°c

at up to 50% thermal efficiency.

Can assist a cooling, refrigeration or intercooling process in the application.

Zero emissions and relatively safe

at point of use: Emits only air or

nitrogen; “Fuel” is non-flammable.

Relatively low capital cost. Air-engine potentially simpler and cheaper than future ICE in same

production volume LN2 tank £40/kWh as one-off; potentially <£25/kWh in

production volumes. Few “exotic” materials in engine or

cryogenic tank, unlike battery or FC/H2. Low embedded carbon

in manufacture.

Made with common materials and processes:

What defines a Lair engine as different

A stand-alone zero emission engine (ZEV) exhausting cold air; highly relevant for on-and off-highway applications, including industrial (i.e. fork-lift trucks, mining and inland waterways applications, as well as the built environment.) Longer term, a ZE city car.

Cryogenic engine uses classical engine technology to provide a clean at point of use, light weight (compared to e.g. batteries), compact engine that can also harness low grade waste heat.

A very high yield low-grade heat energy recovery system; to be integrated with an internal combustion engine (or fuel cell); this could practically increase overall fuel efficiency by up to 30%.

A cost-effective and zero-emission combined power and cooling solution; (applicable to mobile refrigeration – a multi-billion $ global retrofit market). Refrigeration currently accounts for approx. 8% of a chilled delivery vehicle’s diesel consumption. Air conditioning can be as high as 20%+ in hotter climates.

Three primary applications

ZEV markets are diverse, and conventional solutions are not perfect – certainly there is room for an alternative.

ZEV transport markets: Indoor goods handling & mining Port and inland vessels Airport vehicles Urban transport – car

How can Liquid Air compete? • Capital cost of first products potentially lower

than BEV (e.g. car similar) • W2W CO2 similar to FC/H2/electrolysis today

future potential <30g/km W2W • Lifecycle CO2 competitive with EV & FC • Existing LN2 infrastructure, especially for early

captive or return-to-base applications

Zero Emission Vehicles

In heavier vehicles, it makes more sense to use the cryogen to recover waste heat from an ICE.

Incumbent WHR solutions: • Turbo-compounding – used in larger

trucks, rail marine & off-highway, FE & CO2 benefit limited to 5-10%

• Rankine Cycles –very costly, again limited to 10% FE & CO2 benefit

How can Liquid Air compete? • Low capital cost– bus system 25%+

improvement in fuel consumption • Potentially has similar 3yr payback

to flywheel-hybrid • Existing LN2 infrastructure fit-for-

purpose for depot vehicles “Warmant” heat exchanger

LN2 engine

IC Engine Gearbox Driven Axle

Power combiner

Waste heat to power

Baseline Extreme downsize

Practical downsize

Commentary

ICE power (kW) 200 46 120 Practical downsize retains some highway & hillclimb capability

ICE capped output (kW) n/a 23 50 Practical unit capped at higher level to reduce LN2 tank size

ICE BSFC (g/kWh) 240 210 220 Taken from generic map

Transiency BSFC factor 17% 8% 8% Baseline matched to 7.5mpg TfL data; hybrid reduces factor

Diesel used per day (litres) Base -58% -26% Depends on operating strategy – extreme d/size makes more use of DE

LN2 used per day (kg) 0 699 186 Extreme LN2 tank packaging would be a challenge?

DE max operating time on cycle & at full power (sec)

n/a 10 / 6 50 / 19 Based on ICE thermal inertia, 20c drop. Extreme needs heat store

CO2 saving today 0 Worse 0% Pessimistic grid-mean used

CO2 saving 2030 0 48% 23% Saving against a 20% better baseline – better if baseline static

Illustrative results for a standard 12m bus on the MLTB cycle – diesel & CO2.

Impact modelling

Refrigeration is a promising market – can use both coldness of liquid air and expansion work.

Incumbent refrigeration solutions: • Existing units are ICE driven – from main

engine in vans, APU in trucks & reefers • These tend to be optimised for low

capital cost and high reliability – account for ~8% of refrigerated transport CO2

How can Liquid Air compete? • Using a liquid air engine (to recover

expansion energy) can increase that CO2 benefit to +80% (today’s LN2 carbon intensity), with payback over evaporation-only system in ~2 years

“Warmant” heat exchanger

DearmanEngine

IC Engine Gearbox Driven Axle

Refrigerated Payload

Refrigerated transport markets • Global sales of refrigerated transport

equipment have double-digit growth, predicted >£6bn by 2015

• Developing economies growing fastest, as agriculture & food production modernise

Cooling/ refrigeration

Driver operated refuelling systems already in use in Europe to support use of LN2 in refrigerated transport. Can deliver LN2/LAir at 100litres/minute.

3m

12m

Existing industrial gases industry, including distribution network. Also produced on site at many heavy industrial plants. An urban bus would require about 190kg of LN2 per day to achieve a 25% diesel fuel saving. The tank on the right would be suitable for refuelling ~300+ hybrid buses per day.

Fuel/ infrastructure

Many applications with a business case; no infrastructure barrier.

Liquid air can compete in a number of markets: Zero Emission Propulsion: Similar range to BEV, faster refuelling, lower capex (good for low utilisation) Can compete on lifecycle CO2 if LN2 “fuel” is made intelligently. Waste Heat Recovery from an ICE: Solutions for short and long haul offering ~3 year payback and 25%+ CO2 reduction. Refrigeration: >80% CO2 benefit ; 2 year payback. Infrastructure is no barrier to early deployment Existing industrial gas production and distribution fit-for-purpose and extendable.

Some conclusions

Test engine by end 2013 and proof of concept vehicle early 2014. Development Programme

Test engine by end 2013

Proof of concept vehicle early 2014

Refrigeration

2013 Test Engine

2014 Proof of

Concept Vehicle

2015 First Field

Trials

PHASE 1: Engine

operating at constant speeds

Refrigeration Retrofit market LN2 already used for refrigeration on vehicles to replace diesel.

Waste heat to power (PHASE 1) Constant speed engine harnessing waste heat of IC engine or fuel cell. Can service in-vehicle auxiliary power.

Combined power and cooling Combination of two applications above.

PHASE 2: Dynamic engine

Waste heat to power Dynamic engine to provide auxiliary power + additional primary power alongside IC engine (i.e. acceleration, start-stop).

+ Cooling Both with and without cooling.

Primary zero emission power train

Dynamic primary zero emission engine for off-highway applications.

PHASE 3: Zero emission primary powertrain for on-highway applications – passenger vehicles, urban delivery vehicles etc.

Commercial timelines - field trials from 2015

Research begins with the University of Leeds

LAES Timeline

2005 2006 2007 2008 2009 2010 2011 2012

Cold recovery cycle proved viable in lab experiments

Power recovery cycle demonstrated in lab-scale tests

Installation of complete pilot CryoEnergy Storage plant

Installation of power recovery cycle in pilot plant

2013

Commercial design and build

A 350kW/2.5MWh pilot plant hosted by Scottish and Southern Energy; fully integrated into the local distribution network, and in operation since April 2010

Award winning technology

LAES – how does it work?

charging

High Grade

Cold Store

Hot Thermal

Store

storage discharging

Power Out

Compression

Expansion

Air Out

Evaporation

Power In

Compression

Air In

Expansion Tank

Refrigeration

Thermal recycle doubles the cycle efficiency – 60%

LAES – what does it look like?

* Cantarell oil field, Mexico 50,000 TPD liquefier ~ 5,000 MWhrs per day

** GE Generator loaded gas expander 80MW capacity available today

*** Isle of grain LNG facility Each tank 190,000m3

~ 16.6GWhrs

Key attributes

Liquid Air Energy Storage

Above ground CAES CAES

Flow batteries Pumped hydro

1 10 100 1000 MW

Village Small town Large town/City Regional/ National

• Can harness low grade waste heat

• Highly cost competitive - once mature, competitive in cost to a CCGT

• The system can be delivered today at the 5 -100MW scale

• Not constrained by geography

• Configurable/ flexible

Cost

• 20 MW / 80MWhr • FOC - £1,774/kW • 20th - £995/kW

Option 1: Make more

• 200 MW / 800MWhr • ~£500/kW • Dinorwig 580/kW • £1000/kW more typical today for

pumped hydro

Option 2: Make it bigger

Pilot Plant

Complies with all the regulations and inspections necessary to be allowed to connect the system to the UK grid. Successfully undergone a full testing regime, including automated performance testing for the US PJM electricity market. Operating hours equivalent to three years of UK Short Term Operating Reserve service; operated for seasonal TRIAD management.

The pilot plant has the following characteristics: • 300 kW turbine output • 30 tonne/day liquefier • 2.5 MWhrs storage • Turbine inlet temperature range 20 to 60oC

PJM Test Data – Auto control

Gene

rato

r Exp

ort (

kW)

Commercial products

The Highview CryoEnergy System: A fully integrated energy storage system, capable of being scaled up to 100s of MWs. The exhaust is cold air.

Two basic product sets

The Highview CryoGenset: Liquefaction and power recovery are at separate locations (with truck delivery from the liquefier to the storage tank/power recovery unit). The CryoGenset can be thought of as similar in operation, to a diesel generator (e.g. back-up/security of supply/peaking plant), but zero emission. With the CryoGenset, the cold is not recycled, but is available for providing cooling for a co-located host process.

Commercial or industrial processes

Large energy demand Must-run process A peaky energy demand profile Low - medium grade heat sources available Increasing energy cost Grid under stress Embedded renewable energy sources

LNG terminal

LNG Ship Storage

Grain Power Station

Heat

Regasification

Gas transmission system

Heat Pipe Direct fired or

Waste cold

LAES + LNG

Expansion

Power Out

Air Out

Discharging

Evaporation

Low grade heat from heat pipe

LAIR Storage

Hot Thermal

Store

Compression

Cleaning

Refrigeration

Air In

Charging Storage

Power In

Cold from LNG

Power and transport integrated on grid

On and off highway

Cooling / Refrigeration

Cold from LNG (Optional )

Tank

Liquid air transported onsite

Co-generation or industrial processes

Waste heat (convert to additional power)

Cold storage

Tank

Surplus / ‘waste’ electricity Peak/security

of supply electricity Power

Recovery Liquefaction

Liquid Air Energy Storage

Waste heat (convert to additional power)

Peak shaving or remote back-up power

Power Recovery

Cooling

Zero emissions remote back-up power

Power and transport integrated off grid (i.e. in a mine)

Cooling

Waste heat (convert to additional power)

Off highway

Off highway ZEV or heat recovery hybrids

Co-generation or industrial processes

Liquid Air Energy Storage

Cold storage

Tank Power

Recovery Liquefaction

Peak shaving or remote back-up power

Off grid / renewable generation

Timeline

Market Pull Solution implementation

• Solar and wind are now mainstream Utility supply options

• Environmentally in tune

• Globally renewable power penetration of grids unstoppable

• Fully scalable to grid requirements

• Emergent renewable heat agenda globally • No new materials science

• New grid scale storage solutions – no real answers yet

• Thermodynamics well understood

• Developing world food supply chain needs cold storage and chilled transportation

• IP landscape well described

• Cost of cooling • Waste heat to power • Strong supply chain

Why might Nitrogen work?

Toby Peters founding Director

Liquid Air Energy Network

Highview Power Storage & Dearman Engine Company

www.liquidair.org.uk

toby.peters@liquidair.org.uk