Solar Thermal

Make use of the South West’s glorious sunshine and turn it into free hot water. 



What is solar thermal?

Solar Thermal heats water using one or two solar panels which are typically fitted to your roof although larger arrays can be ground-mounted if needed. The panels contain a liquid called glycol which is heated by the sunlight that falls onto the surface of them. This liquid, when heated by the sun, is pumped to your hot water cylinder where is it used to heat up your domestic hot water supply. Solar Thermal panels are robust and durable and extremely effective. 

Why is Solar Thermal different to solar panels?

Solar PV (photovoltaic) generates electricity whereas Solar Thermal focused solely on heating water. Solar PV captures the suns rays to generate the electricity and Solar Thermal collects heat, meaning they will operate even on cloudy days.

How does it work?

Solar Thermal works by collecting daylight to heat a liquid contained inside tubes within the panels. This liquid is then transferred through an exchanger coil to heat the water in a cylinder. They work well combined with a boiler which can meet high demand during times of less sunlight. 

Does it have to be sunny for Solar Thermal?

Solar Thermal panels offer effective year-round performance because the tubes will heat up in daylight as opposed to only clear sunlight. This means they work when the temperature is cooler or if it is cloudy or overcast.

How much can you save with Solar Thermal?

The great thing about Solar systems is that sunlight is free! From April through to November, you can expect Solar Thermal systems to meet around 90% of your hot water demand. In the Winter months the Solar Thermal systems should be able to adequately pre-heat your hot water reducing your overall energy cost for your hot water. Solar is a renewable heating system thus reducing your carbon footprint and doing your bit for the environment whilst saving on energy costs. 

Is my house suitable for solar thermal?

Most homes will be suitable for Solar Thermal but there are some considerations. Your roof’s aspect ideally should be South-East to South-West with a tilt of about 30 to 40 degrees. However, if you have a flat roof, mounts can be installed to allow for optimum placement of the solar panels. The less shading from nearby trees and buildings the better and the number of residents in your home will affect the size of the solar panel installation that you need to meet your households needs.

Geographical location will play a part and the wonderful advantage of living in Devon and Cornwall is that you may benefit from the longer daylight hours. Cornwall gets around 1541 hours of potential water-heating sunshine per year!

What grants are available for Solar Thermal?

Due to the government-initiated scheme, the Renewable Heat Incentive RHI has driven the increase in the use of renewable heat technologies like Solar Thermal and Biomass in domestic homes. 

The scheme pays participants each quarter based on the calculated energy use for the property in that time, lasting 7 years. The payments are index-linked so the rate of the payments per kWh increase in line with the consumer price index. 

More recently the government has released the Green Homes Grants which could cover up to two-thirds of energy efficiency and low carbon heat improvements like Solar Thermal, in your home. There are larger grants available for those who receive a qualifying benefit.


The Benefits of Solar Thermal