Great fun for learning solar and practicing soldering on these small solettes so you become expert without much cost.

See my other listing for solar flux pens busbar and tabbing wire; EVA encapsulation sheet or pre-build panels.

The 52x19mm solettes weigh 0.5g each andare rated at 0.5V and 0.14 watt so 40 pieces is just over 5 Watts with lots of voltage combinations.

The 52x38mm solettes weigh 1.1g each and  are rated at 0.5V and 0.28 watt so 20 pieces is just over 5 Watts; 40 pieces is just over 10 Watts

The 52x76mm solettes weigh 1.9g each are rated at 0.5V and 0.56 watt so 10 pieces is just over 5 Watts ; 20 Pcs is just over 10 Watts and 40 pieces is enough for over 20watts

Efficiency of Polycrystalline is approx. 14%

Voltage of each cell (all sizes) is 0.5V just the current is more on the larger cells.