What is a solar hot water system?

Solar water heating or solar thermal is direct heating of water from sunlight. Fluid circulates through efficient solar collectors, usually positioned on the roof, where it is heated and used to heat the hot water cylinder or heat store. A solar hot water system includes the collectors, a new hot water cylinder and control system as well as all the pipe work and connection with your boiler. A good solar collector is typically about 90% efficient at converting solar energy into usable heat.

Can I use the hot water for radiators?

This is not usually possible - mainly because you will want the heat during winter months when there is least sunlight. A large number of solar collectors would be required but they could be used to heat an outdoor pool in the summer!

If you have, or are planning to install, alow temperature space heating system, like under floor heating, then it's possible to make a contribution from solar heating. We can provide special Consolar heat stores for this purpose. A larger solar array will be required and this sort of system needs to be considered at the design stage of a new build or major refurbishment.

What happens if it’s a cloudy day?

You may still have hot water from the day before as the cylinder will be very well insulated. At times when you have not got enough hot water your boiler will automatically cut in to heat the water.During the summer and sunny days in spring and autumn you can expect most of your hot water to be provided by solar power. In winter and for the rest of the spring and autumn, the solar system will contribute to the hot water requirement and reduce the load on the boiler. Some people even turn their boiler off for 6 months of the year, this will save on boiler maintenance costs. 

With a larger, well stratified store, such as one of the Consolar heat stores , it is possible to store heat for several days - which means even less demand on the boiler.

Can I generate electricity?

A solar hot water system will heat water only. To generate your own electricity you will need photovoltaic (PV) panels or a micro wind turbine. Photo-voltaics are still relatively expensive, although grants are available  (up to £2,500) for household systems. Systems cost from about £7,000 for a fully installed grid connected domestic system without a grant. Domestic wind turbines are developing rapidly and we are keeping tabs on things whilst the commercial offerings come in stream. 

What else should I consider?

First things first, before you consider generating your own power whether it’s solar water heating or electricity you should check some basics, for example have you insulated your property? You wont be able to get grants unless you’ve got good loft insulation and cavity wall insulation if your property is suitable. It’s also sensible to make sure you have an efficient central heating boiler. If you’re boiler is 10 years old or more you’ll help the environment and save more money by installing an efficient modern boiler. You should also have thermostatic controls on your central heating and an automatic timer controller to turn heat on only when you need it. Don't forget the grants also question whether you have energy efficient lighting. 

What’s the payback period?

This is a tricky question and depends on unknowns like the future price of fuel. However this article from the Guardian suggests that if you have the money then installing solar power is a better investment than leaving your money in the bank. You shouldn’t consider just the rate at which you save money on fuel but also that a solar power system adds value to yourhome and makes you feel good!

What else can I do at home to save energy and reduce carbon emissions?

Try to use as little energy as possible. Keep heating systems turned down and wear more clothes instead. Install A or A+ rated appliances and low energy light bulbs. Get a smart meter to show you how much power you’re using. Consider using wood as a fuel particularly with a wood burning stove which is much more efficient than an open fireplace. It’s also possible to get wood burning stoves which are fired by special pellets although you’ll need a lot of storage space and supplies are not very developed as yet.

What area do you cover for installing solar systems?

We will install domestic solar water heating systems within an hour of our offices in Stroud, Gloucestershire. For larger commercial installation we will consider work further away. See our installation area map .