SOLAR for HOT WATER and HEATING

Here Comes the Sun - London Solar: heat with care

WHAT SOLAR HEATING HAS TO OFFER…

• A MATURE & WELL ESTABLISHED TECHNOLOGY• VERY WIDESPREAD APPLICATION• SOLAR HEATING is a VERY LOW CO2 EMITTING TECHNOLOGY• EFFICIENT CONVERSION of LIGHT to HEAT• VERY GOOD for HOT WATER and CAN WORK VERY WELL for HEAT• COMBINES WELL with CONVENTIONAL HEATING SYSTEMS & OTHER

RENEWABLE TECHNOLOGIES

HERE COMES THE SUNSOLAR for HOT WATER and HEATING:

• A MATURE & WELL ESTABLISHED TECHNOLOGYsolar water heating is ‘OLD TECH’…In California, USA “CLIMAX” Solar Water Heaters were sold & installed from

1890’s.Clear standards for design & manufacturing:

EN 12975 test standards for solar collectorsEN 12976 for ‘intrinsically secure’ design & installation

The UK market is now well regulated through the Microgeneration Certification Scheme (MCS)

Product & Installation standards for a range of renewable technologiesThe UK has the world’s longest established trade body for solar technologies…

The Solar Trade Association

HERE COMES THE SUNSOLAR for HOT WATER and HEATING:

• A MATURE & WELL ESTABLISHED TECHNOLOGYInstallation standards are much higher in Britain now.

A STANDARD SOLAR HEATING SYSTEM … … is INDIRECT, separate from the water we use … has GLAZED, INSULATED solar collectors … has mains-powered circulation pump … uses SOLAR-SPECIFIC components: pumps, valves, insulation etc

HERE COMES THE SUNSOLAR for HOT WATER and HEATING:

• VERY WIDESPREAD APPLICATIONlatest global statistics (source: IEA SHC):

over 400 million sq.m. solar collector area installed around the world (40,000 hectares = around 56,000 football pitches of collector area)

Approximately 300 GigaWatts = 300,000 MegaWatts capacityAround TWO THIRDS of total global capacity is in one country...

TOTAL installed solar collector area in UK in 2005 was around 100,000 sq.m.ANNUAL installed area around 100,000 sq.m. in UK now.

HERE COMES THE SUNSOLAR for HOT WATER and HEATING:

• SOLAR HEATING is a VERY LOW CO2 EMITTING TECHNOLOGYassuming it has been appropriately chosen, well designed & installed…a solar water heating system will: consume around 50kWh of energy a year to run provide between 1000 and 1800 kWh useful energy a year offset a further roughly 25% of efficiency loss for a (modern, efficient) gas boiler

TOTAL ENERGY OFFSET perhaps around 1500 to 2000 kWh a year

NO NEED TO WAIT FOR THE ELECTRICITY GRID TO GO GREEN OR RELY ON OTHER PEOPLE REPLANTING BIOMASS

HERE COMES THE SUNSOLAR for HOT WATER and HEATING:

• EFFICIENT CONVERSION of LIGHT to HEAT MAXIMUM CONVERSION EFFICIENCY OF A SOLAR COLLECTOR over 80%... REALISTIC OVERALL SYSTEM EFFICIENCY around 50%

compares well to the Internal Combustion engine: around 15 to 20%and very well to PLANT GROWTH, around 1 – 2%

This makes SOLAR THERMAL COLLECTORS VERY SPACE-EFFICIENTthis helps solar heating systems do a lot with a small area:For solar water heating a collector area of around 4 sq.m. is commonFor space heating & combi’ systems, a typical collector area is between 6 and 12 sq.m.

HERE COMES THE SUNSOLAR for HOT WATER and HEATING:

• VERY GOOD for HOT WATER and CAN WORK VERY WELL for HEAT

SOLAR CAN WORK VERY WELL FOR HEATING BUILDINGSThere are more constraints and complications than for water heating:NEEDS: a well-insulated building that can be heated at lower temperatures (just as for heat pumps to

work effectively) a larger collector area and more storage by some means.

“COMBI-SYSTEMS” that do heating and hot water are common across Europe, now most of solar collector area installed in Germany, Austria, much of France

STORAGE & DISTRIBUITION OPTIONS ARE MULTIPLE & MORE COMPLEXAPPROPRIATE DESIGN IS VERY IMPORTANT

HERE COMES THE SUNSOLAR for HOT WATER and HEATING:

• VERY GOOD for HOT WATER and CAN WORK VERY WELL for HEAT

SKYRAD – UK patented design, installed in London & Birmingham, solar thermal & External Wall Insulation for ‘hard to heat’ solid wall buildings - costs around £16,000. Gas savings around 85%, data from installed systems.

COMBI-SYSTEMS with THERMAL STORESa range of options available, highly dependent on buildings & occupants’

heat needs

HERE COMES THE SUNSOLAR for HOT WATER and HEATING:

• SOLAR THERMAL is useful for HOT WATER AND HEAT

TYPICAL INSTALLED COSTS – materials & labourSOLAR HOT WATER: system (without storage) £2700 to £3600high-efficiency hot water store: £800 to £1800

SOLAR SPACE HEATING varies more widely: £8500 to £18000

HEAT & ENERGY USEOver 80% of the energy we use in our homes is for HEAT

• Average domestic hot water demand around 2,500kWh, though varies widely

• Typical hot water storage losses between 500 and 800kWh per year

• Poorly insulated pipework and cylinders can loose up to 2,910kWh per year

• Well-installed solar water heating system can save 1,500kWh of hot water energy

Installation Step Energy Bill Saving per year

More efficient boiler Possibly very large

New cylinder with 75mm insulation or added jacket

£45

Pipework insulation £15

Solar Thermal £55 replacing gas£88 replacing electric

How does it work?

S1

S2

S3

S1

S2

S3

Collector temperature

Upper hot water storetemperature

lower hot water storetemperature

When S1 is hotter than S3, the controller switches the pump on, which circulates the heat transfer fluid. This warms the hot water cylinder.

Renewable Heat Incentive

19.2p/kWh for hot water provided by solar water heating for 7 years.The total amount over 7 years ranges between £1,200 and £3,200.Amount of hot water depends on:• Occupancy• Hot Water Usage • Boiler Efficiency Green Deal assessment required for eligibility• Loft must be lagged to at least 250mm• Cavity walls must be filled.

Legacy customers since 15th July 2009 included.