# 12v summerhouse lighting



## trev.h (Mar 26, 2002)

I wish to install some lighting in a summerhouse, on a bidget and without running mains cables.
I thought I could use a 12v lead acid battery and a 12v solar powered trickle charger (maplins £19.99) with 12v Ikea lighting.
Any thoughts?
Anyone got any ideas what safety features to install into the circuit?


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## JohnWill (Oct 19, 2002)

Well, 12V is pretty safe, though I'd certainly install circuit breakers in the circuits. Other than that, just follow normal safe wiring practices.


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## Soundy (Feb 17, 2006)

12V circuit breakers are _relatively_ rare and expensive... you can get automotive fuses and fuse holders super-cheap at any auto parts store, if you're concerned about circuit safety.


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## Knotbored (Jun 5, 2004)

If this is just lighting to prevent bumping into furnature you might consider those "bump" lights that work on AA batteries. I have a few scattered in dark basement corners and they work great, although I wouldn't read by them. They also have cheap solar chargers, but you would have to remove/replace them into the lamps.
I have an old travel trailer that has propane stove/frig and 12V battery lighting-would be good for a cabin setup like you describe. Perhaps you can find a wrecked or damaged one to salvage the electrical system from. I suggest a small generator for weekends the sun doesn't cooperate.


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## cwwozniak (Nov 29, 2005)

trev.h said:


> a 12v solar powered trickle charger (maplins £19.99) with 12v Ikea lighting.
> Any thoughts?


Is this the £19.99 charger you were considering:

http://www.maplin.co.uk/module.aspx?ModuleNo=47902&doy=24m4#overview

The specifications list it as having a 1.5 watt output and it seems be designed for maintaining a charge on a vehicle battery in storage. At that power output rating it could take a very long time to recharge a battery that is even used for one evening to power some lighting.

For example, running 15 watts of lighting for one hour from a 12 volt battery would require using that charger for at least 10 hours in full sunlight to fully recover the charge.


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## kiwiguy (Aug 17, 2003)

I use an identical unit to keep my ATV battery charged at my seaside cottage.

On a bright sunny day you are looking at about 80 mA (0.08 Amps) and overcast day about 20 mA (0.02 Amps).

You will only get that for the daytime "sunshine hours".

Now a 10 watt 12v lamp is "not much light", but for every hour it is "on" it will take about 12 hours of full sun (2 to 3 days), or 40 - 50 hours (a week or so) of overcast but bright light. Just for 1 hour of low light (10 watts).

Also be aware that you cannot run the battery down to near flat, that charger could never "catch up". 

You need a better solar panel.


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## trev.h (Mar 26, 2002)

This is great stuff.
Knotbored. Planning on using the summerhouse for the kids to house their pool table, dartboard etc.
cwwozniak. Yes, that is the unit.
kiwiguy. Yes, I think you're right, but I can't find anything of a comparable price (maplins are always fairly cheap). Maybe 2 units wired in parallel? 
I was planning on using 2 heavy duty batteries from a breakers yard to hopefully give sufficient lighting time.


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## cwwozniak (Nov 29, 2005)

trev.h said:


> Maybe 2 units wired in parallel?
> I was planning on using 2 heavy duty batteries from a breakers yard to hopefully give sufficient lighting time.


Your problem is not so much the size of the batteries to give you enough energy to run your lights for a few hours every evening. You need to be able to fully recharge them every day to be ready for the next evening. Enough solar panels to do that is not going to be inexpensive. You may need something more along the lines of this product from Maplin:

http://www.maplin.co.uk/module.aspx?ModuleNo=97378&doy=24m4

As *kiwiguy* pointed out, the smaller solar cells you were looking at are only useful to keep a fully charged battery topped off during storage.


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## JohnWill (Oct 19, 2002)

I think the price is a bit steep for what he was looking at.


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## Knotbored (Jun 5, 2004)

Here is one 45 watt for $200(USA) that might be more reasonable.
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=90599

by the way-Harborfreight sells lots of inexpensive tools, they are not pro quality but are perfect for 99% of my amature needs. I have not used that splar charger, but am thinking about getting it to keep my mower battery charged.


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## cwwozniak (Nov 29, 2005)

JohnWill said:


> I think the price is a bit steep for what he was looking at.


Still cheaper than buying 33 of the £19.99 models to get the equivalent charging capacity.


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## JohnWill (Oct 19, 2002)

Sure, but probably way out of the budget.


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## kiwiguy (Aug 17, 2003)

The "heavy duty" batteries from a breakers yard are likley to be past their best, so the solar panel (even 2 of them) would probably only be enough to overcome the standing losses, without any actual drain.

How far away from the house supply is this "summerhouse"?
I have a remote structure in our gardens that I supply lighting to at 12v, using a 14v AC supply about 150 metres away, with very heavy duty (old scrap overhead LV insulated cable) wires saddled to the bottom fence rail. Worked fine for years now.


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## JohnWill (Oct 19, 2002)

I think I'd use a high powered laser to transmit the power. 

Not really...


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## cwwozniak (Nov 29, 2005)

JohnWill said:


> I think I'd use a high powered laser to transmit the power.


Let us not forget Nikola Tesla's wireless method ... 










www.crystalinks.com/tesla.html


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