Solar thermal systems use the sun’s warmth to heat some of your hot water. Fluid inside solar collectors (panels) on your roof absorbs irradiance from the sun. It’s then pumped along pipes to your hot water cylinder, heating up the water to a preset temperature. Your boiler or immersion heater then tops up the heat as needed, bringing the water to the temperature on the thermostat. Run yourself a nice relaxing bath to celebrate – you’ll be saving money every time you turn on the hot tap.
A solar thermal system will work best in summer, when it can heat up to 90% of the hot water you use. But it will still save you money all year round and can even be designed to contribute towards your heating costs. Thanks to the government there are some tempting financial incentives too.
Solar thermal technology has lots of advantages – it’s low maintenance, it will save money year after year and the system is relatively inexpensive compared with other microgeneration technologies. So how much do you need to invest, and what will you get back?
Depending on how you use it, a well-designed and properly sized solar thermal system can help you make a substantial saving on your bills. You can expect it to provide:
Systems can also be designed to contribute towards heating your home, and could reduce heating costs by up to 60% over the course of a year.
You’ll make the biggest saving if your hot water is currently heated by electricity, followed by oil and then gas. However, the actual savings you’ll make on your bills will depend on how you use your hot water. The best way to find out what you could save is to talk it through with us.
The cost will depend on a range of factors including the number of panels, the complexity of the plumbing and the suitability of your existing hot water system. A typical system would cost around £5,000 to £5,500, and you’ll be able to get £300 towards this from the government as part of the upcoming Renewable Heat Incentive
You may be able to receive payments for the heat you generate from a solar water heating system through the government’s Renewable Heat Incentive.
You may also be able to get help with the installation costs of a new solar water heating system through the Renewable Heat Premium Payment scheme.
Maintenance costs for solar water heaters are generally very low. Most come with a five year or ten year warranty and require little maintenance and just a few checks regularly. The solar water heater and pump should be checked by an accredited installer every three to seven years. The pumps can last for ten years plus.
How well a solar thermal system will work for you depends on your lifestyle and when you tend to use the majority of your hot water or heating. If you’re in during the daytime and use your hot water mainly in the evenings, solar thermal is ideal. If the house is empty during the day and you use most of your hot water first thing in the morning, you won’t be getting the full benefits. However, you can get round this by installing a larger hot water cylinder, which will allow you to store more hot water overnight.
It’s a good idea to time your boiler or immersion heater so that it tops up the heat in the early evening, when the solar thermal system has been working all day. The water can then be used later that evening or the following morning. On a warm day, you may not even need to use your boiler or immersion heater at all.
Using a solar thermal system for heating is an option and can be especially effective if you have underfloor heating, or you don’t have a mains gas supply. Systems designed to supply heating are larger than those providing hot water alone, so you’ll need a bigger roof space and bigger hot water cylinders. However the long-term benefits could make it a worthwhile investment. To find out whether it could be a good option for you, just talk to one of our team.