The basic facts
Solar panels will provide about half your annual hot water. On sunny, summer days they will do it all. On wet, winter days they contribute a negligible amount.
A truly reliable, hybrid, eco-friendly system might combine solar in the summer with a wood-burning stove with back boiler in the winter.
Solar can also be fitted in conjunction with any fossil-fueled boiler. To work out the likely saving on your gas or oil bill, you need to consider that your radiators, if you have them, will typically account for about 70% of the fossil fuel you buy, so solar replaces half of the remaining 30%.
There are six different types of solar thermal systems:
The differences may appear subtle to the layman but are important to get right to suit your individual needs. Beware of firms which offer a one size fits all panel.
A well-maintained system will last indefinitely. The only moving part is a circulating pump. Modern pumps consume negligible power (about £2 of electricity a year).
A truly reliable, hybrid, eco-friendly system might combine solar in the summer with a wood-burning stove with back boiler in the winter.
Solar can also be fitted in conjunction with any fossil-fueled boiler. To work out the likely saving on your gas or oil bill, you need to consider that your radiators, if you have them, will typically account for about 70% of the fossil fuel you buy, so solar replaces half of the remaining 30%.
There are six different types of solar thermal systems:
- Flat-plate, pumped
- Flat-plate, gravity
- Direct flow tubes
- Heat-pipe tubes
- Drain-back
- Solartwin
The differences may appear subtle to the layman but are important to get right to suit your individual needs. Beware of firms which offer a one size fits all panel.
A well-maintained system will last indefinitely. The only moving part is a circulating pump. Modern pumps consume negligible power (about £2 of electricity a year).
Things to watch out for
Some people have been overcharged by firms employing high-pressure salespeople. If you get a mail shot and you send back the reply-paid card, you waive your legal right to a 'cooling off' period. There have been several cases of firms declaring bankruptcy and then setting up under a new name, with no legal responsibility for outstanding guarantees and service agreements.
Always get a variety of quotes before you decide - and don't just go for the firm with the glossiest brochure. Never sign an agreement on the spot - take your time over the decision.
Always get a variety of quotes before you decide - and don't just go for the firm with the glossiest brochure. Never sign an agreement on the spot - take your time over the decision.
The bottom line
A good, family-sized solar water-heating system, including a new hot water cylinder, should cost around £4,000. A really simple one can be as little as £2,000. A really smart, high-tech complicated one could cost £6,000. A competent DIYer could buy and install his/her own system for about £1,500. These prices assume you need a new hot water cylinder, and this is not always the case. The Renewable Heat Incentive (RHI) would repay you about £1,500 on a typical system. Note that you don't qualify for RHI if you DIY.