Solar security light

[studentspark]

Have to light up an area that has no power , and getting power there will be tricky and expensive.
Thinking about solar security lights. Never seen any working.
Are they a waste of time or can they do a job - All year round?

Been looking at this one..

Thanks

http://www.gardenitems.co.uk/products/Solar-Secure-V2-Professional-Solar-Security-Light.html

 

[Iggifer]

I too would be interested if anyone has fitted one, as a friend has a detached garage (a long way detached) and wants a floodlight so she can see to get into the garage in the dark

I could run SWA to it but it's not the easiest of routes.

I'd been looking at these:

http://www.bltdirect.com/solar-powered-led-flood-lights-1

 

[bernardgreen]

Compare the size of the solar panel in these fittings with the size of the solar panels used to power traffic signs which only need to illuminate a LED sign for a few seconds at a time.

My feelings ( and some experience ) are that these solar security lights will not give bright illumination for more than a few minutes per night and even less if there was no bright sunlight the day before.

 

[ericmark]

With large solar panels the MPPT or PWM regulator extracts the maximum power over an extended time but with small panels the quiescent current means these are not an option.

The diagram shows the problem although this is for 12 volt not 3.6 volt it shows how with the standard regulator the charge time is very limited.

A friend had a solar panel for his Iphone which while working abroad worked very well but in the hills of Wales was a complete failure. Shadows cast by buildings, hills and trees can so change what the panel can produce there can't be a one size fits all answer.

Paying £20 for whole kit when the regulator would cost £8 means it can't really be expected to use PWM regulation and with NiMh AA batteries neither will there be any ΔV charging so to stop over charging the charge rate must be quite low.

I am sure there will be places where they will work but it will be limited and in Winter you will likely need to charge batteries.

The one I looked at says 8 hours for full charge and 25 seconds per activation so without the solar panel it should last some weeks and swapping batteries once a week is not too bad I suppose?