A Perspective on Heating Technology Heat driven heat pumps the - - PowerPoint PPT Presentation

A Perspective on Heating Technology

Heat driven heat pumps – the future of domestic heating?

Bob Critoph Director, i-STUTE University of Warwick R.E.Critoph@warwick.ac.uk

UKLPG Annual Conference 6th October 2014

• Context
• Introduction to technologies
• Market potential in the short term
• Barriers to development
• Market potential in the longer term

Context

• The UK is

committed to a reduction in greenhouse gas emissions

• f 80% by

2050 across all sectors

The Carbon Plan: Delivering our low carbon future. Presented to Parliament pursuant to Sections 12 and 14 of the Climate Change Act 2008 Amended 2nd December 2011

Context

• The UK is

committed to a reduction in greenhouse gas emissions

• f 80% by

2050 across all sectors

Building a low-carbon economy – The UK’s contribution to tackling climate change. The First Report of the Committee on Climate Change December 2008 London: TSO . ISBN 9780117039292

Context

• In 2011, RCUK initiated a call to fund up to six

interdisciplinary Centres in ‘End Use Energy Demand’. Each Centre would be funded for five years initially with a nominal budget of £5M.

• i-STUTE was awarded one of the centres and

funding commenced from April 2013 – its distinctive feature is concentration on heating and cooling.

• 47% of fossil fuels in the

UK are burnt for low temperature heating purposes (25% of CO2 emissions)

• 16% of electricity in the

UK used to provide cooling - Worldwide it represents 10% of greenhouse gas emissions

Why heating and cooling?

Heat 47% Transport 39% Other 14%

Energy Consumption by end use 2012

Provisional data for 2012 (DECC)

Heat 47% Transport 39% Other 14%

Energy Consumption by end use 2012

Domestic 57%

Service 19% Industry 24%

Heat Use by Sector

Provisional data for 2012 (DECC)

i-STUTE coverage in red

Space heating 63% Water heating 14% Cooking/caterin g 5% High temperature process 6% Low temperature process 9% Drying/seperatio n 3%

Heat use by purpose

Gas 71% Oil 7% solid fuel 3% Electricity 15% Heat sold 2% Bioenergy & Waste 2%

Breakdown by fuel of total heat use

i-STUTE coverage in red

The largest component is in space and water heating – What do we plan to do about it?

Projects in Space Heating

Task Compact chemical heat store Compact latent heat energy storage Advanced electric heat pump Next generation gas powered heat pump Heat emitter study

Projects in Space Heating

Task Compact chemical heat store Compact latent heat energy storage Advanced electric heat pump Next generation gas powered heat pump Heat emitter study

Limitations of the energy infrastructure – why the future will not be renewable electricity and electric heat pumps.

Source: Energy Technologies Institute, 2012

2010 UK heat & electricity hourly demand variability

Design point for heat delivery system Design point for electricity delivery system Peak electricity demand will exceed electrical grid capacity in future

??

• Domestic Heat pumps cannot economically provide the

high powers (25kW) required for instantaneous hot water production

• Grid limitations prevent even close to 100% of

instantaneous demand heat pumps.

100 GWe

500 1000 1500 2000 2500 3000 3500 4000 4500 Other Air/Ground heat Heat Pump Electric load Power

100 GWe

GWh/d Days

180 360

In excess of 3 times the peak capacity needed? 35-40million heat pumps?

Source: S. Marland, National grid, Why hybrids and gas heat pumps?, GasTech seminar 19th March 2012

1 in 20 Peak Network Electricity (with Fast Charge)

2000 4000 6000 8000 10000 12000 14000 16000 18000 20000 00:00 02:00 04:00 06:00 08:00 10:00 12:00 14:00 16:00 18:00 20:00 22:00 Time of Day Consumption (kWh/6min) 2010 2050_GG 2050_ER

4 – 7 x Electricity distribution network capacity needed? Rewire +250,000km in 15-30 years?

Source: S. Marland, National grid, Why hybrids and gas heat pumps?, GasTech seminar 19th March 2012

What ways are there of addressing the problem?

1) Hybrids

• Hybrid electric heat pump/gas boilers have been suggested as one

solution but as the housing stock thermal performance improves, DHW provision will become a larger fraction of the total load.

Source: E. Sutherland, Bosch, Bosch Hybrid, GasTech seminar 19th March 2012

3kw Air to Water Heat Pump Gas Condensing Combi Boiler

Source: Cliff Jones, Itho UK, GasTech seminar 19th March 2012

1) Hybrids

• Hybrid electric heat pump/gas boilers have been suggested as one

solution but as the housing stock thermal performance improves, DHW provision will become a larger fraction of the total load.

• 2. Compact chemical/latent heat store

Chemical heat store (long term)

• Objective is to develop a POC chemical

thermal energy storage and delivery system with an energy density of at least five times that of a comparable water store able to deliver all of its heat at a temperature of 65˚C.

• Challenges are materials selection,

reactor and system design, instantaneous effectiveness, long term system performance. Latent heat energy storage (short term)

• A nearer to market interim solution to the

challenge

• A phase change latent heat energy

storage approach. Energy density is several times greater than water but subject to parasitic heat loss over time.

• This project will develop and test a

prototype system scalable to meet 2-4 hours of maximum winter space and water heating load.

• Another approach to the problem – heat storage

Advanced compact heat stores can smooth out the diurnal peaks

• n the grid. They are part of a complex solution that involves

hybrids, gas fired heat pumps and perhaps other technologies. Good for trimming peak loads over a day, important but not enough!

• 3. Gas heat pumps
• Another option is the gas fired heat pump – three domestic, many

commercial products on or near market:

Introduction to technologies

Technologies

• Engines

Introduction to technologies

Introduction to technologies

Technologies

• Engines
• Sorption
• Absorption
• Adsorption

Introduction to technologies

• Absorption
• Adsorption

Performance similar in principle Refrigerants similar:

• Water
• Ammonia
• Methanol

Introduction to technologies

Introduction to technologies

• Absorption
• Adsorption

How do they work???

Introduction to technologies

Electric heat pump

High pressure gas Low pressure gas Liquid Heat from

• utside air

Heat to radiators 3 kW

2 kW 1 kW (e)

Electrically driven compressor

COP ≡ = 3 Heat out . Electricity in

Introduction to technologies

High pressure gas Low pressure gas Liquid Heat from

• utside air

Heat to radiators 3 kW

2 kW 1 kW (e)

Compressor COP ≡ = 3 Heat out . Electricity in Motor

Electric heat pump

Introduction to technologies

High pressure gas Low pressure gas Liquid Heat from

• utside air

Heat to radiators 0.9

kW 0.6 kW 1 kW gas

Compressor COP ≡ = 1.5 Heat out . Heat (gas) in

0.3 kW work

Gas engine

0.6 + 0.9 = 1.5 kW

Gas engine heat pump

Introduction to technologies

COP ≡ = 1.5 Heat out . Heat (gas) in

• Wins on fuel cost
• Wins on CO2 emissions
• Maintenance, noise etc

rule out domestic applications Gas engine heat pump

Introduction to technologies

Low pressure gas Liquid Heat from

• utside air

Heat to radiators

1.3 kW 0.3 kW 1 kW gas

COP ≡ = 1.3 Heat out . Heat (gas) in High pressure gas

Absorption heat pump

2) Low pressure ammonia gas dissolves in water 1) Low pressure ammonia liquid boils in evaporator 3) Pump ammonia solution to high pressure 4) Heat solution to drive out gas at high pressure 5) Gas condenses to liquid at high pressure

Introduction to technologies

Low pressure gas Liquid Heat from

• utside air

Heat to radiators

1.3 kW 0.3 kW 1 kW gas

COP ≡ = 1.3 Heat out . Heat (gas) in High pressure gas

Absorption heat pump

2) Low pressure ammonia gas dissolves in water 1) Low pressure ammonia liquid boils in evaporator 6) Weak solution throttled back to low pressure to absorb more gas 4) Heat solution to drive out gas at high pressure 5) Gas condenses to liquid at high pressure

Introduction to technologies

Low pressure gas Liquid Heat from

• utside air

Heat to radiators

1.3 kW 0.3 kW

COP ≡ = 1.3 Heat out . Heat (gas) in High pressure gas

Absorption heat pump

1 kW gas

WHAT IS IN THE BOX IS A HEAT DRIVEN COMPRESSOR

Introduction to technologies

Adsorption heat pump

Introduction to technologies

Adsorption heat pump

Pressure

40º C 170º C 40º C

Initial State: Ambient Temperature Low pressure High concentration

0º C

Introduction to technologies

Adsorption heat pump

Pressure

40º C 170º C 40º C

Process 1 Carbon bed is heated, ammonia is driven off and pressure increases until…

Heat Input 0º C

Introduction to technologies

Adsorption heat pump

Pressure

40º C 170º C 40º C Heat Input

Process 2 starts The saturation pressure is reached and ammonia condenses in the right hand vessel at ambient temperature.

0º C

Introduction to technologies

Adsorption heat pump

Pressure

40º C 170º C 40º C

Heat to water

Process 2 continues More ammonia is driven out from the carbon and condensed in the right hand vessel

Heat Input 0º C

Introduction to technologies

Adsorption heat pump

Pressure

40º C 170º C 40º C 0º C

Heat to water

Process 3 The carbon is cooled, the concentration increases and the pressure drops.

Introduction to technologies

Adsorption heat pump

Pressure

170º C 40º C 0º C

Heat from

• utside air

Heat to water

Process 4 The carbon is cooled towards ambient and the concentration increases. Ammonia boils in the right hand vessel giving the refrigerating effect.

40º C

Introduction to technologies

Adsorption heat pump

Pressure

End of Process 4: The system is returned to the starting condition

170º C 40º C 0º C 40º C

The net effect is just the same as in a liquid adsorption system but this is a batch process rather than continuous – as a user or as a specifier

• r as an installer you do not care about the difference!

Existing and near market products:

Vaillant

Technical data of zeoTHERM VAS 106/4 Rated heat output range Heating 1,5-10 kW Rated heat output range d.h.w. 4,2-12,5 kW Adjustable flow temperature 20-75 °C Recommended max. flow temperature HC < 40 °C

• El. power consumption max. 100 W

Appliance width 772 mm Appliance height incl. flue outlet 1.700 mm Appliance depth 718 mm Transport weight (without casing) 160 kg Operating weight 175 kg Integrated controller zeolite module > no moving parts / no maintenance

Introduction to technologies

Existing and near market products:

Vaillant system:

• Water refrigerant, zeolite adsorbent
• heat pump ,solar collector, water storage tank
• Only intended for use with underfloor heating

systems with Maximum output temperature of 40C

• Claimed reduction of annual energy use of 18%

compared with a condensing boiler.

• Initial system sale price was around €16,000.

Introduction to technologies

Existing and near market products:

Robur

• Ammonia water absorption
• Air, water and ground source options
• DHW at 65C (gross COP 1.24)
• 38 kW to radiators (supply

temperature 50C) COP of 1.52 (gross), 1.38 (net).

• Saving of about 40% in gas

consumption compared to a condensing boiler.

• Single module 854(w) x 1256(d) x

1281(h).

• 18kW unit, is under development.
• The product is ‘badged’ by BDR

Thermea and Bosch

• 40kW unit is c. £12,000.

Introduction to technologies

Existing and near market products:

Introduction to technologies

Existing and near market products:

Introduction to technologies

Existing and near market products:

Sorption Energy

Change in product concept over time of project: 1.5 m 0.5 m 0.4 m Where has the rest of the hardware gone?

Introduction to technologies

Existing and near market products:

Sorption Energy Fits into standard wall-mounted casing

Box-for-box exchange for

• ld boiler

Key competitive advantage

• ther gas-fired heat

pumps too large for wall mount Retrofit market >90% of annual sales

Adsorbent Beds (Generators)

Introduction to technologies

Other wacky ideas etc…

Boost Heat Cooll ThermoLift ….

Introduction to technologies

One of these types of heat pump will eventually win out over the gas boiler – we just do not know which one yet! But this is not just about being green, we need to be commercial – what are the markets, what are the barriers???

Market potential in the short term

Competing with gas boilers rather than electric heat pumps

2 4 6 8 10 12 14 2004 2005 2006 2007 2008 2009 2010 Units (millions) Year

World domestic boiler market

Others Italy South Korea UK

UK market largest in world at c. 1.5 M units p.a. 1.1 M are ‘distress purchases in private houses

Market potential in the short term

Competing with gas boilers rather than electric heat pumps What influences consumer choice? Regulation

Market potential in the short term

Competing with gas boilers rather than electric heat pumps What influences consumer choice? Installer

• Familiarity with boiler (installed them before, received

training from manufacturer, accredited installer)

• Easy and quick to install (weight/ fittings). Must be a

‘one man fit’.

• Good back-up support from manufacturer should there

be a problem e.g. spares available

• Performance/ reliability (if the boiler breaks down it will

be under warranty (2 years generally) from the manufacturer, but the installer will be called back).

• Incentives: manufacturers sometimes give vouchers to

installers for each boiler installed.

Market potential in the short term

Competing with gas boilers rather than electric heat pumps What influences consumer choice? Customer

• Capital cost (can be important if an unplanned / distressed

purchase). [Note that RHI might mitigate additional capital cost]

• Performance.
• If anything other than simple condensing boiler is suggested

then payback likely to be important. Base point is a standard condensing gas boiler (£1800+VAT, incl installation). Pay back in three years for mass market

• Availability of finance – to cover capital cost can help influence

decision

• Physical size/ noise
• Advertising/ brand: There has been some but limited brand

building

• Recommendation from friend

Barriers to development

• Specifier/Installer training
• Consumer Behaviour
• Capital cost
• Safety
• Noise
• Life/reliability

How can we make heat pumps desirable???

Market potential in the longer term

The limitations of the energy infrastructure

Source: Energy Technologies Institute, 2012

2010 UK heat & electricity hourly demand variability

Design point for heat delivery system Design point for electricity delivery system Peak electricity demand will exceed electrical grid capacity in future

??

Market potential in the longer term

Figure 56, National Grid, Future Energy Scenarios 2012

Market potential in the longer term

The Future of Heating: Meeting the challenge, DECC, March 2013 Dense urban 22% Suburban 59% Rural 19% UK Housing Stock Time

Thank you for your attention

• Any questions?