Home & Garden

For some time, I have taken an interest in solar water heaters. These are simply arrays of pipes containing a liquid that are mounted outside and are heated by the sun. The liquid inside is then passed through a heat-exchanger to heat a tank of hot water. It’s a little like a central-heating radiator used in reverse.

Commercial solar water heaters are very expensive. One designed to supply enough hot water for an average family costs in the region of £7,500, installed, at time of writing.

Anyone with basic DIY skills could build one for considerably less than that. I estimate that I could build one, including a solar array, new hot water cylinder, controller, pump and pipework for under £500.
Fitting it to the roof of most houses might be beyond the capabilities of many DIYers, but I’m fortunate enough to have a flat-roofed porch that gets long exposure to the sun. It’s low enough to access without having to resort to scaffolding towers and I have worked safeley up there before (painting the house).

So the plan is to construct one of these heaters over the winter period (2011/2012). Although solar heaters do work on sunny days in the winter, the main benefit will be during the warmer months.

It’s a long-term project that will be spread over the winter whenever I find the time. This will give me time to locate the parts at the best prices. I shall construct the various components of the system as I acquire the parts.

And the first parts are on their way. A colleague is renovating his house and is disposing of some old secondary double-glazing panels. These are basically large sheets of glass set in aluminium frames. They will be ideal for making the lid of the solar collector boxes.

I’ll post some photos as I acquire the parts, and during construction, so that anyone else interested in building their own solar water heater can see how I do it.