Hi All,(adsbygoogle = window.adsbygoogle || []).push({});

Please forgive me as its a few years since I did my A-Level Physics. However I am now a retail designer and just trying to figuring out how to light a shop window using Solar Power.

I'm pretty sure its not possible but I am determined to do the maths to prove that its not. I need to light a shop window, however it is in a mall. The window will be lit from large lights above, however I was wondering whether these large lights would be able to power smaller spots using solar panels. The idea being that if we used solar panels we could put certain spotlights in locations that are unreachable by wires. I understand that this is highly inefficient, but as the light is shining from above already the question was posed in the office as to whether it could be done?

So I have the spot lights I would like to use and an example of a solar panel. I can't find an equation to calculate the power of light that would be needed above to power the smaller spotlights. Some of the initial calcs (Rusty physics knowledge from my school days) are laid out below.

LED Spot light

4w @12vdc

4/12= 0.34amps

0.34amps x 8hours = 2.67amp-hours

Solar Panel

Output voltage: 18V

Output current: 277mA

Output power: 5W

5Wx8hrs = 40Wh s

40whs/12 = 3.3amp-hours

Thank you in advance for your help.

Kind Regards,

Luke

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# Solar Powered Light for Shop Display

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