How do solar water heating systems work?

Solar water heating is one of the most popular forms of renewable energy use in the UK, helping thousands of households across the country to save money on their energy bills. A solar thermal system can satisfy around a third of a typical household's hot water needs, cutting heating bills and increasing your disposable income.

How solar water heating works

Solar water heating systems capture the sun's energy through a network of solar panels installed on your roof, before using that power to heat your water, which is then stored in a hot water cylinder. You can use the system in conjunction with a regular immersion heater, which will kick in when your solar supply runs out.

There are two types of solar water heating systems to choose from - the standard flat-plate collectors, which resemble regular solar panels, or the more innovative evacuated tubes, which take up far less space.

What are the benefits of solar water heating?

The main benefit of a solar water heating system is lower energy costs - the more water you can heat in this way, the less money you'll spend on heating bills. Typical savings can range from between £55 to £80 a year, although the bigger your property and the more panels you have, the higher your eventual savings will be.

Solar water heating can also drastically reduce your home's carbon footprint, while you can keep installation costs to a minimum with a £300 grant from the Renewable Heat Incentive Premium Payment scheme.

What are the drawbacks of solar water heating?

One of the main drawbacks of a solar water heating system is that it won't cover your hot water bills completely; you'll still need to keep, maintain and power a traditional immersion heater to provide you with hot water when your solar supply runs out.

You may also be put off by the initial installation costs, which can fall anywhere between £3,000 and £5,000 - at least ten times the £300 government grant.

What is the future of solar water heating?

If the initial outlay is too much for you at the moment, you may want to hold off on installing a solar thermal system until after the introduction of the Renewable Heat Incentive. This is a government initiative that will eventually guarantee users regular tariff payments for 20 years, allowing them to recoup the costs of their installation. Payment amounts will depend on the amount of heat generated and the amount of excess power available to feed back into the national grid.

How to choose a solar water heating system

The solar thermal system that you choose will largely depend on the size and location of your property, as well as your budget and the amount of money you are looking to save. It can be a hassle finding the right system - efficiency is key in order to maximise your roof space and keep the hot water supply flowing.

On average, you'll need around one square metre of solar panelling per person in your home, and having a large water storage tank is advisable. You will also need to install new piping in order to link your new system to your existing network.