Setting up Solar Water Heating

We want to replace our ancient electrically heated water tank with a new modern one that can be heated by a solar panel and be topped up by electricity when required.

Has anyone constructive advice about who to use and what to look out for, including price and good manufacturers of tanks etc. We are Dept 16.

The French are exceptionally well ahead with solar heating/power, but unfortunately it hasn't taken off like they were hoping it would and that's at least 20 years ago! However, every house in Crete and the Cook Islands has solar heating for their water, and the air/water heat exchanger is additional and very efficient. I can't specifically recommend any particular companies, but recall serious system studies being done at Sophia -Antipolis and different light industrial manufacturers in Antibes, Valbonne and Vallauris. (Solar panels are becoming very popular on sail boats, not just for electrical power, but for heating water as well).

Good luck

Interesting about the big exchanger air to water. Could you upsize (!) this to cope with central heating?

Sir, you are disparaging the name of all us Essexovians, I demand satisfaction - pistols at dawn. Not all of us are wide boys and Towie is made in Grimsby any way.

Our water in the house and barn (used as a holiday gite during the summer) is heated by electricity unless we have the oil fired boiler running so this system looks interesting as the boiler is 30+ years old and is a bit expensive to run. Any cost comparisons on systems?

Yes Rob, quite possibly as normal hot water would arrive at probably 50c at most on a dual H & C fill machines. There is some concern with state of the art types that too higher in coming water temp could throw up a fault code and cause a shut down but I haven't heard of any cases of this but that seems mainly because people are unwilling to risk their warranty on an experiment to save a few pounds.

Does that shorten the wash time down? obviously most wash times are based on a cold fill and time to heat the water, don't know if that's by sensor which you should naturally reach the point faster with the warm fill.

It's a similar issue on dishwashers which need much higher water temperature but as you say apart from commercial machines the water is normally heated after the rubber parts. Good news these days a lot of these parts are now silicon so very temperature resistant.

Since the house is heated by a woodburning boiler with a sanitary hot water system connected to it I brought hot and cold water to the (French, thus cold only) washing machine and fed warm water to it through a regular thermostatic shower tap set at pl. 40 C .

One could imagine that water at too high a temperature would damage the intake lines (plastic).

Normally the water is heated after it has entered the stainless steel bassin in which the drum turns. Any part afterthat is apparently made for higher temps.

Limiting the intake to 40 C does it for most washes and reduces heating up time for hotter ones.

Our neighbours in the next hamlet have an ultra-expensive heat refracting shutter. The original one they had did not prevent their tubes getting hot at all, perhaps a couple of degrees. So they replaced with this contraption. They are not saying but the way they are not saying means it is a lot of money. However, they worked all of this summer, so on that count they are pleased.

Hi Clare, yes boffin, geek etc but a friend lost some of hers so we are looking towards a roller blind idea but also to shut the light off a bit when things are all warmed up and no requirement for anymore heat. I couldn't sleep if it started hailing, I still haven't actually made my mind up yet, been monitoring others feedback.

Our hot water is fed from after the mixer exiting the cylinder. We can fill anything from cold up to 60c.

Here is another possibility for DIY-ing:

:-D Seems like you are having a light bulb idea John!!! Its the hailstorms that do my head in. We have had them as big as golf balls of late when we have had them and I suppose they are a huge risk. A friend of mines guttering had massive holes made in them when we had the last one. Imagine the damage to the solar!!

That's the sort of thing I really hate, you try to save the world a bit at a time and a pig insurance co try to remove the benefits you may enjoy!

Some kind of roller blind to cover the tubes in the event of hailstorm giving a few cms of protection is maybe what's needed.

Ours is linked to our log burner back boiler as well. Our insurers, just to clarify, wanted to know if we had them but will not cover the units in the B & C policy without an extra premium. And, yes I know that is steep.

My new insurer was only interested in knowing if I had photovoltaique panels. I told her about the solar heating panels and she said they weren't an issue.

By the way, my panels were supplied by Wagner, a German company which has accredited installers in France. As someone said, the best investment I ever made. The hot-water tank is also linked to our Okofen wood pellet central heating boiler which tops up the temperature when, like now, there isn't enough sun to heat the water.

Crikey thats steep!

Yes and some insurers will not give cover for them included in your cover unless you pay an additional premium. We spoke to AXA, who insure our house about ours, and they wanted a premium equal to the cost of the whole of the buildings and contents together extra.

One thing I have noted from my insurer is I have to declare the solar installation in order to be insured from adverse weather etc. Useful to check

And another to add is you may qualify for the prime energetique so do look on the ademe site

Just to add that the work does qualify for the tax credit and reduced tva of 5.5% if installed by an rge professional, the regs all changed in oct so its worth looking on the ademe website for info. The eco loan at 0% is very interesting if you have sufficient income vs debt ratio.


they are based in the Charente - use the Kingspan solar thermal system

Tax credits are available at 30% for solar thermal - need to have the same company fit and supply and to get them the kit has to be soalr keymarked and they need to be RGE certified on 1st jan 2015. reduced rates of TVA also apply. good luck