Why Solar Thermal?

In the UK, up to 60% of annual domestic hot water requirements can be supplied by solar heating. Solar thermal collectors placed on the roof of a property can provide nearly all the water heating required in the summer and provide a useful and energy saving preheat to the cylinder in the winter. A solar thermal array with 4m2 of collection area will provide between 35% and 70% of a typical home’s annual hot water requirements depending on the quantity of hot water required and the timing of that requirement.

How does a Solar Thermal system work?

Solar Thermal technology collects heat from the sun and uses it to heat water. Solar Hot Water panels can either consist of flat plates or evacuated tubes. The panels heat a fluid (typically Glycol) that is then pumped to a special 'twin coil' cylinder. The heated fluid heats the household water within this cylinder to up to 69 degrees where it is stored until needed.

Will a Solar Thermal System heat my home?

Residential Solar Thermal systems are designed to heat water for washing, bathing, etc. Theoretically, the technology could be used to heat water for central heating. However, it would require a much bigger investment and more space to install a system with enough capacity to heat your home. In addition most heating is required in winter when there is least sun. It works best in the summer months and will cater for most of a house’s hot water needs during those months. It takes priority over other heating systems thus using traditional fossil fuel heating systems as a back-up.

How much will a Solar Thermal system save me?

A typical residential Solar Thermal system, on a property with 3 to 5 occupants, will cut the water heating bill by around £55 to £85 per year. From October 2012, residential systems are also likely to receive payments for every unit of heat they generate under the UK government’s Renewable Heat Incentive (RHI). The RHI means that households will receive around £250 per year, which when added to the fuel savings represents a return on investment of between 7% and 8%.

Are there any grants available?

A grant of £300 is available for eligible domestic customers from 1st August 2011. This is known as the Renewable Heat Premium Payment which is intended to bridge the gap until the full Renewable Heat Incentive scheme is launched in October 2012

What is the Renewable Heat Incentive?

The Renewable Heat Incentive (RHI) is designed to encourage more use of Renewable Heat in the UK. Residential properties with Solar Thermal Panels will earn payments for every unit of heat generated from October 2012. RHI Payments come directly from the UK Government and for domestic properties are likely to be 8.5p per kW of heat generated.

How do I know if my property is suitable for Solar Thermal?

Solar Thermal panels can be installed on most properties with 3m2 to 4m2 spare on the roof, providing there is sufficient un-shaded roof space facing West, South West, South or South East. You should own the property and if it is a listed building or in a conservation area, you should seek planning permission before proceeding further.

Do I need to change the hot water cylinder?

It is likely the hot water cylinder will need to be changed as the new cylinder should have a solar coil fitted. ‘Combi’ boilers can be used with solar thermal panels as long as the boiler manufacturer recommends this or if the system is changed to a cylinder based setup. In changing the cylinder setup the hot water performance is also enhanced.

* all figures sourced from the Energy Saving Trust - www.energysavingtrust.org.uk