100W solar panels for only £27

Will be testing one of these soon, with a view to eventually powering my shed with them, this is a great price, typically you pay £70-80 for a 100W cell so i'm not expecting great performance but you never know!

https://www.ebay.co.uk/itm/100W-Flexible-Solar-Panel-Polycrystalline-Module-Cell-Charger-Farmer-Car-Boats/283693206643?hash=item420d6ecc73:g:6woAAOSwhQpd4OCO

I copied this from the specs

Vpmax:18V

Power: 100W

Ipmax: 2.77A

Output: 5V/18V

18v * 2.77A = 49.86 watts if my calculator is correct.

...R

Probably 100w at 5 volts...

Qdeathstar:
Probably 100w at 5 volts...

I presume that's a joke

...R

100/(0.2800.6621368) = 39.4% efficient

The highest efficiency solar panels can reach almost 23 percent efficiency.

Someone is lying. And it's a whopper. I suspect I know who.

Robin2:
I copied this from the specs
18v * 2.77A = 49.86 watts if my calculator is correct.

...R

Note to self - must stop believing ads and read the details!

Hi,
From this site;

Solar panels are given a power rating in Watts, based on the amount of electricity they can produce in one hour of peak sunlight. However, these ratings are classified under ideal conditions in a laboratory, and therefore don’t represent the amount of power that could be expected of that panel on a day-to-day basis. So a 250W panel installed on a household rooftop, is not going to produce 250 Watts of electricity, even in peak sun.

Tom.... :slight_smile:

Hi,

You have to do a load test to find Maximum Power Point.

Tom... :slight_smile:

The figures I used in Reply #1 claim to be the voltage and current at the max power point.

...R