solar panel silly questions!

[Thermo]

Sorry if this sounds like a bunch of daft questions!

I have a set of stables on a farm that i rent as my storage for my landscaping business. There is no electric to the stables and i would like to be able to put a couple of lights inside so i can see if i need to pop in when its dark to pick up any tools etc or possibly charge the odd drill battery etc when im working there. Im after a basic solar panel kit to do this. I suppose the longest a bulb would be on would be 30 minutes or so. The stables are on a hill top and get plenty of direct sunlight.

Would a kit such as this be sufficent, if not any other ideas advice?

http://cgi.ebay.co.uk/FULL-20W-18V-...ryZ41981QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

many thanks

Thermo

 

[electronicsuk]

While cheap and cheerful, if the specifications of the solar panels are to be believed then most of the kit will have no problem running a couple of flourescent lights for half an hour, assuming they don't mind being fed from an inverter.

I would question whether or not the battery included with the kit is really suitable, seems to be that a 2.2Ah battery would quickly become charged on a sunny day and as soon as that happens any more power the panels generate is wasted. If the charge controller supports it then you might consider upgrading to a 6Ah lead acid battery.

As for charging drill batteries, it once again comes down to the inverter and whether or not the design of the charger will cope with the modified sine wave output from the inverter. It's possible that anything with a charge cutoff timer might not work as intended, but you'll wont know if your specific model works until you try it! I also wouldn't want to leave it running unattended, as the inverter will soon drain the included battery even through quiescent current if left running all night.

 

[Bargeman]

Hello,

I would suggest you try posting this query on the Navitron forum (www.navitron.org.uk/forum). You will find that it is one of the best repositories for information on all the renewable technologies, including photovoltaics.

I agree with previously posted comments about battery capacity and the need to be careful about matching the DC/AC inverter to the loads. Cheap inverters are notorious at generating crude AC waveforms that can create problems for less robust/more particular appliances.

regards

Justin

 

[bernardgreen]

If it is only for lighting and charging power tools then you may be able to do it without the wasteful inversion to 230 V AC.

There is a wide range of 12 or 24 volt flourescent lighting equipment designed for automobile use. They have self contained invertors matched to the tube and are therefore very efficient. Labcraft Ltd make a good range of lights.

Many power tool chargers take a low voltage from a power module in a "13 amp plug top" ( wall wart ) and in many cases a 12 or 24 volt DC supply can replace the wall wart.

 

[Bargeman]

The ebay listing states "Our Solar Panels have a high energy conversion of 15% + and a 18 V operating voltage, which makes it ideal to charge 24V batteries."

I would be very sceptical. I am not aware of any commercially available monocrystalline pv that will generate at efficiencies of greater than 15% even under ideal irradiation conditions.

The idea that 18v is sufficient for charging at 24v is fanciful. Neither statement inspires any confidence that they know what they are talking about.

regards

 

[Thermo]

ok thats kind of confirmed my thoughts!

so being a complete arse at electrics what do i need to do it? Ayone know of any kits etc