Professor Nigel Brandon OBE FREng

Director, Energy Futures Lab

Director, Hydrogen and Fuel Cell SUPERGEN Hub

www.h2fcsupergen.com

www.imperial.ac.uk/energyfutureslab

Progress in Fuel Cell mCHP

Prof. Nigel Brandon – Imperial College, Dr David Book – Birmingham Univ.,

Prof. Paul Ekins – UCL, Prof. Anthony Kucernak – Imperial College, Dr Tim

Mays – Bath Univ., Prof. Ian Metcalfe – Newcastle Univ., Prof. Vladimir

Molkov – Ulster Univ., Prof. Robert Steinberger-Wilckens – Birmingham

Univ., Prof. John Irvine – St Andrews., Prof. Nilay Shah – Imperial College.

Contents

• Why mCHP?

• Why fuel cells for mCHP?

• Current status of fuel cell mCHP.

• Summary.

Fuel

Fuel

Cell Fuel

Heat

Electrical

50%

40%

Energy

100%

Power station

55% losses

Transmission

5% losses

Delivered

40%

Fuel Cell

10% losses Delivered

90%

Energy

100%

Conventional

Micro-CHP

Fuel Cell Boilers for the Home (micro-CHP)

Contents

•Why mCHP?

• Why fuel cells for mCHP?

• Current status of fuel cell mCHP.

• Summary.

Source: UK Energy Sector Indicators. 2011. DECC.

Heat: 39% UK CO2

Power: 33% UK CO2

Transport: 28% UK CO2

89.8% fossil in 2010

UK: Share of fuels contributing to primary energy supply

UK: Ownership of central heating

Source: GfK Home Audit from the Domestic Energy Fact File. Building Research Establishment.

Does electrification of heat make sense?

– The UK has signed up to challenging targets of ~80% CO2 reduction by 2050. Many studies to date have focussed on low carbon electricity as the key enabler for this transition, supporting the increased electrification of transport and heat.

– But there is increasing recognition of the extremely high system costs arising from delivering this vision.

• e.g. analysis of UK electricity demand if electrical heat pumps are used to displace gas in the heating sector showing the large increases in peak load

(Adapted from: Hawkes AD, Brett DJL, Brandon NP, (2011) Role of fuel cell based micro-cogeneration in low carbon heating, PROC

IMECHE PART A-JOURNAL OF POWER AND ENERGY 225 pp198-207).

A Smart and Low Carbon Gas Grid

– Predicting flows in the UK national gas grid is becoming more challenging. Changes are being driven in part by gas power generation balancing unpredictable wind power generation.

– There will be an increased role and value for high deliverability energy storage. We have recently explored the economic benefits of energy storage, showing a value of the UK energy system of as much as £10B per annum by 2050 for some scenarios [Strbac et al, for the Carbon Trust].

– Increased potential for load shedding/shifting across energy vectors - e.g. shifting heat or cooling load to accommodate balancing activity.

– Fuel cells offer very efficient coupling of gas and electricity networks, on natural gas, bio-gas, hythane, or hydrogen.

– Gas will therefore be a key partner in future smart energy networks, coupled (potentially) to electricity by high efficiency fuel cells.

Micro-CHP Technologies

Baxi Stirling engine Panasonic PEMFC

Ceres Power and British Gas SOFC

Honda ECOWILL ICE

Honda ECOWILL ICE with Storage

Fuel

Fuel

Cell Fuel

Heat

Electrical

50%

40%

Energy

100%

Power station

55% losses

Transmission

5% losses

Delivered

40%

Fuel Cell

10% losses Delivered

90%

Energy

100%

Conventional

Micro-CHP

Fuel Cell Boilers for the Home (micro-CHP)

0 4 8 12 16 20 240

2

4

6

8

10

12

14

16

Time (Hours)

Dem

and (

kW

)

Space Heating and DHW Demand

Electricity Demand

Residential heat and power demand

Heat and Power Demand over 1 Day in a Typical UK Dwelling

Contents

• Why mCHP?

• Why fuel cells for mCHP?

• Current status of fuel cell mCHP.

• Summary.

Economic Drivers for m-CHP Systems

• Dwelling Annual Electricity Demand •The main value driver for micro-CHP is (the ability to displace) onsite electricity demand. •If onsite electricity demand exists, the ability to access the value available (in displacing it) is dependent on the heat-to-power ratio (HPR) and presence of thermal demand.

0 2500 5000 7500 100000

200

400

600

800

1000

1200

IC Engine

0 2500 5000 7500 100000

200

400

600

800

1000

1200

PEMFC

0 2500 5000 7500 100000

200

400

600

800

1000

1200

SOFC

0 2500 5000 7500 100000

200

400

600

800

1000

1200

Annual Electricity Demand (kWh/year)

Maxim

um

Cost

Diffe

rence B

etw

een

Mic

ro-C

HP

Syste

m a

nd B

oiler

Syste

m (

£)

Stirling Engine

Low Thermal Demand

Average Thermal Demand

High Thermal Demand

HPR = 1

HPR = 3 HPR = 2

HPR = 8

Dwelling Annual Electricity Demand

Hawkes, AD, Staffell, I, Brett, DJL, Brandon, NP, Fuel Cells for Micro-Combined Heat and Power Generation, Energy &

Environmental Science, 2009, Vol: 2, Pages: 729 - 744

5000 10000 15000 20000 25000 300000

500

1000

1500ICE

5000 10000 15000 20000 25000 300000

500

1000

1500PEMFC

5000 10000 15000 20000 25000 300000

500

1000

1500SOFC

5000 10000 15000 20000 25000 300000

500

1000

1500

Annual Thermal Demand (kWh/year)

Annual C

O2 R

eduction w

.r.t. R

efe

rence S

yste

m (

kg C

O2/y

ear)

)

Stirling

Flat

Bungalow

Terrace

Semi-Detached

Detached

Environmental Drivers for m-CHP Systems

CO2 Reduction – Thermal Demand •CO2 reduction is dependent on ability to displace grid electricity. •Ability to displace grid electricity, and thus bring about CO2 reduction, is dependent on annual thermal demand and prime mover heat-to-power ratio.

Hawkes, AD, Staffell, I, Brett, DJL, Brandon, NP, Fuel Cells for Micro-Combined Heat and Power Generation, Energy &

Environmental Science, 2009, Vol: 2, Pages: 729 - 744

marginal CO2 intensity of UK

electricity 0.69kgCO2/kWh

Contents

• Why mCHP?

• Why fuel cells for mCHP?

• Current status of fuel cell mCHP.

• Summary.

Fuel Cell micro-CHP deployment in Japan

ENE FARM programme

Tokyo Gas Co., Ltd., Toho Gas Co., Ltd., Saibu Gas Co., Ltd., Shizuoka Gas

Co., Ltd., Keiyo Gas Co., Ltd., Osaka Gas Co., Ltd., Hokkaido Gas Co., Ltd.

Hiroshima Gas Co., Ltd. and Odawara Gas Co., Ltd. are promoting fuel cell

installation in households.

The 2013 model price from Tokyo Gas Co., Ltd. is 1,995,000 yen (£12,800),

down by approx. 760,000 yen from the previous model (tax included,

excluding installation work cost). These are sold with a ten year warranty.

34,000 Ene-Farm units installed in

Japan at end 2012. The goal is to have

5.3 million units installed by 2030. For

this to happen, cost has to be driven

down —the goal is a ¥700,000 to

¥800,000 ($7481 – $8549) price tag by

2016, and ¥500,000 to ¥600,000 ($5343 –

$6412) by 2020. Government subsidies

for Ene-Farm end in 2015.

- Fuel cell unit -

Fuel type City gas (13A)

Electric output Rated output 750 (W)

Output range 200 - 750 (W)

Heat output Rated output 1080 (W)

Output range 210 - 1080 (W)

Electricity generation efficiency (rated) LHV:39%

(HHV:35.2%)

Heat recovery efficiency (rated) LHV:56%

(HHV:50.6%)

Total efficiency LHV:95%

(HHV:85.8%)

Dimensions

Width: 400

Depth: 400

Height: 1850 (mm)

Mass (in drying operation/in operation) 90 (kg)/95 (kg)

Maximum electricity consumption 500 W (at startup), excluding freeze

protection

Noise level 38 (dB)

Panasonic ENE FARM PEMFC unit

Four manufacturers are producing ENE-FARM products: Toshiba, Nippon Oil, Aisin Seiki, and

Panasonic. Panasonic’s is a 750W system; the rest are 700W. Electrical efficiencies for the

units range from around 38% to 45%, depending on the specific unit and fuel. Overall energy

efficiencies are around 90%.

Ceres Power SOFC micro-CHP unit

Reduces the energy bill of a customer by around 25% and saves around

1.5 tonnes of CO2 pa. In addition, under the UK feed in tariff (FIT), a

household installing a SOFC mCHP product will receive, for a period of ten

years, a generation payment of 10p/kWh. For a typical UK home with such

a micro-CHP unit, the annual FIT is £436, on top of the predicted annual

energy cost savings of £286.

© Ceres Power 2013 Title: 8th International Smart Hydrogen and Fuel Cell Conference Rev: 1.0

• Thin steel substrate with even

thinner layers of active SOFC

materials coated on top

• Low temperature electrolyte (ceria)

enables operation at <600 oC

• Key advantages:

– Low cost cells

– Compact, lightweight design

– Mechanically tough

– Simple & reliable stack sealing

– Enables low cost balance of plant

The core of the Ceres proposition is its unique metal-supported cell

10

Stainless Steel Substrate

Anode Layer

Ceria ElectrolyteLayer

Cathode Layer

FUEL

AIR

ELECTRICITY

Slide supplied by Dr Mark Selby, Director of Technology, Ceres Power

© Ceres Power 2013 Title: 8th International Smart Hydrogen and Fuel Cell Conference Rev: 1.0

Enables a compact 1kW-Class Stack

12

o 93 to 140 cells

o Cell fuel side sealing by

laser weld

o Compression maintained at

operating temps; low creep

o Pre-formed high temp

gaskets

o Robust seal created on

compression

o ~50mV max voltage

variation across cells in

stack

Designed for simple manufacture and assembly

191.9mm

152.5mm

Weight - 9.3 kg

Volume - 4.1 l

141.4mm

99 cells variant

Weight - 70 g

Single cell

(Including seal)

Slide supplied by Dr Mark Selby, Director of Technology, Ceres Power

© Ceres Power 2013 Title: 8th International Smart Hydrogen and Fuel Cell Conference Rev: 1.0

Highly compact 1kW Fuel Cell Module (FCM)

Design Specification

Maximum electrical power 1000W DC

Minimum electrical power 300W DC

Electrical efficiency (LHV) 50%

Gas supply Natural Gas

Time to first power 2 hours

Electrical ramp rate 3 W/s

Degradation rate 0.5% / khrs

13

STACK

Fuel

Processor

Hx

Slide supplied by Dr Mark Selby, Director of Technology, Ceres Power

© Ceres Power 2013 Title: 8th International Smart Hydrogen and Fuel Cell Conference Rev: 1.0

CTP able to meet multiple start-stops required by real products

20

Ceres metal-supported fuel cell stacks are robust to repeat start-stops

Stack power measurements

at each cycle showing no

power loss

6 cell short stack:

Sealing, Gaskets, Manifolding,

Current collection identical to

stack used in FCMs and CHPs

56% H2/44% N2

3% H2O in Air

140 mA/cm2

Stack cycled from

operating point (590 oC)

to 100 oC

Test intentionally

stoppedRates are furnace

controlled; not

optimised

Tem

pera

ture

C

Time hrsTest Date: Dec 2011 - Jan 2012

Slide supplied by Dr Mark Selby, Director of Technology, Ceres Power

© Ceres Power 2013 Title: 8th International Smart Hydrogen and Fuel Cell Conference Rev: 1.0

• Emergency Stops – immediate cut-off of fuel and air with a thermal cycle

• Other fuel cell technologies can suffer catastrophic damage under this

condition

95%

Stack power measurements

showing 95% power retention

and no loss of cell integrity

Ceres stacks are robust to harshest cycling challenge possible:

Emergency Stops

7 Cell Stack

21

Test Date: August, 2012

Cells survive unplanned shutdowns (RedOx)

Slide supplied by Dr Mark Selby, Director of Technology, Ceres Power

Summary

• There is a need for a smart and low carbon gas grid to

support the move to a low carbon energy future.

• Fuel cells offer the highest possible energy

conversion efficiency between gas and electricity, and

as such have the potential to play a key role.

• Fuel cell mCHP units are now commercially available

in Japan – and European product variants are being

developed.

• The UK has unique technology in this space, offering

significant cost reduction.

Associate membership of the Hub is free and

open to all members of the hydrogen and fuel

cell communities.

www.h2fcsupergen.co.uk