Need help with batteries for solar! and alt. to gas boiler.

[mew]

Hi people,

I'm having grid tied solar PV next year and saw something called the solarmate to run shed lights on [url]www.bettergeneration.co.uk [/url], you get a 10w solar panel, wiring, connections, fuses, light bulbs, bulb holders, and switch. They say all you need is a battery suitable for caravan or car. Can anyone tell me if an old one from a motor garage would be ok, as long as its still running around 12v ish.

Secondly I want to replace the major heating source in the house away from mains gas. However I live in a two bed semi in surburbia, have concrete floors down stairs and I'm a little stumped to how to go really.
any suggestions apart from moving house!

[pomegranate]

I don't think using an old one is a good idea. We use sets of deep cycle 6v batteries in tandum to make 12v, this runs a small household. Also it is not wise to mix and match old and new batteries as tne lod one will drag the new one down. Out here you can also get gel batteries, which are great but are quite expensive. Hope I have been of some help.

[Wombat]

G'Day Mew,

It depends on the load on the battery. 10w is just a trickle charge and I suspect that you will not find it gives enough power, especially that far North. If you do not want to spend the cash, second hand forklift batteries or even car batteries will work but it is buying a pig in apoke (so to speak). You may get a cell collapse the next day or they may run happily for years. The trick is not to deeply discharge them (ie below 12 volts) and not let them get too cold. For experimental purposes, give a car or other similar battery a go. If you are already fair dinkum about this see Pomegranate's post above.

If you want to yern about it PM me.

My article about setting up a 12 volt system is on the site somewhere, but I can't find it. You may want to PM Andy if you want to see it!

Nev

[Muddypause]

Any alternative to main gas could have its own problems. As ever, spend your money on insulation, draught proofing and damp proofing first.

As you are in suburbia you are probably in a smokeless zone, so wood burning is not on. But there are alternative solid fuels that are smokeless, like anthracite. You can get solid fuel burners that have a back boiler for radiators and hot water. You wil need a flue installed for any solid fuel.

Electricity is very expensive as a form of heating, and often pretty unsatisfactory. Storage or convector heaters for background heating and radient heaters for local heating, with an immersion element for hot water.

But if you want an alternative to all this, solar hot water panels on your roof may go a long way to providing much of your hot water needs. And I guess you could consider ground source or air source heat pumps - ground source for preference (sometimes called geothermal heat source), though it will be a fairly major task to installl it. These require a lot of digging to install the heat collector underground where it absorbs heat from the earth. They are best connected to something like underfloor heating pipes which run at lower temperatures than, say, a radiator system. You could install underfloor heating on top of your concrete floors, but you will lose a bit of height in the room, which would give you problems with doorways and things.

I suppose you could consider building a conservatory-type extensiion on the south facing side of the house - a large glass area which will trap the sun's heat. This may work well with the thermal mass of concrete floors, but I'm not too familiar with the requirements of this approach.