Solar Cells – Encapsulation via A4 Laminating pouches . This idea occurred to me recently , i have places id like to put solar arrays such as in windows catching wintertime low sunlight , why allow good light to go to waste ?
Each of these laminates with x2 5x5inch Polycrystalline solar cells encapsulated within produce just over 1volt, making approx 6watts of power in bright sunlight. , with these cells they cost (using ebay ) about £2.00 to £3 per laminate to make, so fairly cheap to to fill otherwise difficult to utilise spaces with solar cells ! This is only the first step, its not really bright enough to test properly today, will continue this script as work progresses .
The Spec of each of these 5x5inch Poly Cells is 0.55v with 3Watts power, so one Lamiate `Panel` will produce 1.1Volts , 6 Watts, so for a good voltage to match a charging systems needs, say 22Volts is needed, so 20 of these laminates wired in series with good thick wire or bus wire would be ideal, to give 120Watt panel total. ( Their Efficiency is 17.5% without encapsulation @ 20`c )
It is well worth remembering that slightly broken cells with corners cracked like the ones shown in this Vid still create the same voltage, just less power / amps, dont throw them away ! test them.
Also worth noting – even a small shadow cast onto just part of a solar cell will pretty much reduce that cells capacity to create power as its internal resistance increases vastly as light diminishes, this means that the other cells , even if in bright sun, cannot pass their current through the shaded cell due to its high internal electrical resistance. Shaded areas like this can produce `hot spots` and burn cell out or damage them. 2 solutions :
1) Dont put cells / panels in dappled shade.
2) Use Bypass Shotky diodes to allow the current to bypass the shaded cell or row of cells. the current rating of the diode needs to allow for the whole cell and panel array current being created in that particular circuit. approx 10 to 20 amp probable, double up on diodes if need to prevent getting hot and being inefficient.
3) also worth nothing , solar cells really detest damp , condensation and water. dont get them wet and seal the cells 100% to prevent condensation ingress.
4) worth checking out `blocking diodes`, prevent current reversal at night or from higher voltage panels in the same system. fitted in line.
Thanks for watching
2016-11-16
Post time: Jun-22-2017