Solar thermal water heating
How it works
Leave a hosepipe in the sun and it heats the water inside. Solar thermal water heating works in a similar way. Solar thermal generates renewable hot water using solar panels (known as collectors) fitted at an optimal angle on a roof. Solar heat warms fluid, usually anti-freeze, in the collectors and this is then pumped to heat water stored in a hot water cylinder. A boiler or immersion heater heats this water further, until it reaches temperatures set by the cylinder's thermostat (60°C).
Solar thermal performance
Energy output of solar thermal relates to latitude and levels of direct sunlight. Some claim that solar thermal can provide up to 70 percent of the average house’s hot water needs, depending on the amount of hot water used and levels of energy efficiency which are put in place. However, the Energy Saving Trust states that a more accurate figure is around 30 percent.
The benefits of solar water heating
- Solar thermal should work all year round during the day but you will need to heat the water further, using a boiler or immersion heater, during winter months.
- Solar thermal can save up to 645kg of CO2 emissions when displacing solar fuel and about 345kg when displacing gas – saving about 10 tonnes over 20 years.
- Along with some biomass wood burning stoves, solar thermal can cost a lot less to install than other microgeneration technologies and it should not cost more than £5000.
- Solar thermal heat is renewable heat (not low carbon heat) and eligjble for grants and the renewable heat incentive from 2011. It is still eligible for grants and listed as eligible in the consultation on the proposed Renewable Heat Incentive from 2011. A decision on the RHI has not yet been taken.
Support
Permitted planning for solar thermal was introduced in April 2008. The Low Carbon Buildings Programme currently supports solar thermal technologies. Solar thermal applications under LCBP Phase One (household stream) are eligible for a £400 grant. LCBP Phase Two provides
grant funding to charitable, community groups and public sector projects. Organisations can apply for 50 percent of the cost of installing approved technologies. Solar thermal is also eligible, if certified products are installed using
MCS companies for the Renewable Heat Incentive from 2011. A decision on a recent RHI consultation has not yet been taken.