Solar Power for Garden Building

Azure11

Sorry if this has been discussed but couldn't find anything when searching.

I'm thinking of installing solar power in my garden building that is going up next week. I guess I will use it for light when needed, heating in winter, small amount of power tool use and things like radio etc.

From what I have read I am thinking maybe something like 150W system might do which seems to cost about £1000. Anyone have any opinions on this? How much power can I store as I may only be using it a couple of times a week? Would I be able to store more if I had another battery or something? (sorry I know nothing about this stuff!)

My garden building will have a South facing sloped roof so hopefully would be good for solar.

Any other advice like best places to buy would be appreciated thanks.

pinnks

Welcome to the mad world of PV.

To be honest, what you describe doesn't sound sensible as it would never pay for itself. In winter you won't generate enough to do more that power a light bulb (during the day??) and in summer you would probably not use what you generate. Storage of what you generate is pretty much a non-starter still as it is way too expensive.

Also, you would probably not be tied to the grid from what you describe so would not qualify for the govt subsidies in the form of the Feed-in-Tariff or FIT.

Would it not make more sense, using your largest roof area(s) to invest a larger amount and put Solar PV on your house, with FITs and all the benefits of generally using what you generate?

Martyn1981

Hiya. Not belittling what you want, but I've read similar questions quite a few times on the Navitron forum.

The answers are almost always the same, even from experienced off-gridders, and that is ..... don't bother. You'll need PV, batts, charge controllers etc.

The alternative suggestion is generally, if a batt will do, then get two, and have one on charge in the house, and buy a sack truck to move them back and for.

I've just finished a side extension (garage without car access), which included a small consumer unit, and a spare fuse for an armoured cable to go to the shed, something I always planned. But even that might not be worthwhile if your garden building is close, as I'm now used to using a 25m extension cable, which works fine.

If your garden building is a reasonable size, then as pinnks suggests, pop a 'proper' PV install up connect it to the house supply, claim any subsidy and export what you don't use.

Mart.

Azure11

Thanks pinnks and Martyn, good to get your views and yes, maybe I should rethink and possibly have a big system which was possibly on my radar in the future.

I think you are right though, it maybe won't be cost effective and I should possibly just get a cable down there (I think it is about 25-30 metres from the house) and then I would have whatever power I might need. Maybe I'll even just ride it out with an extension lead for the time being to assess the situation...

EricMears

If you just want lights in the shed, then a couple of self contained units (LED light unit with internal battery plus small solar panel on 5 metre extension) would do the job at a reasonable price (but a torch is cheaper still )


But that would be absolutely useless for any power tool use or probably even for radio and a large stand alone system would be exorbitant. Laying a cable shouldn't cost a great deal but if it's only occasionally then an extension cable is worth considering - but don't rely on a very cheap (and low current capacity) one : it would always be a temptation to plug in several things at once and melt the cable !

Ectophile

A basic system with a 12V lead-acid battery would be able to power 12V fluorescent or LED lighting. It could even do laptops, radios and small power tools using a small inverter of the sort used in cars.

Big power tools would flatten the battery pretty quick. Heating in winter has no hope of working. You may only get a couple of hours of good sunlight on a winter's day, and that won't do anything useful for heating.