If you start looking at effective achieved energy delivery from solar, 10% is exceptional. Consider that plants are lucky to return 1-10%. Algae, under exceptional conditions, may also reach 10%, but that takes some doing.
Insolation: 1 kW/m^2
Panel efficiency: 10-20%, nominally 17%. Maximum for a single-layer cell is 37% for quantum physics reasons, with an "infinite" layer panel, 87%.
Capacity factor is the amount of time a panel actually recieves sunlightlight. Typically 20-30%, with 30% as a peak.
Spacing factor. PV doesn't work if shaded -- the entire circuit cuts out. So you have to angle and space your panels. On net, this reduces availble area by about 50%. Less near the equator, more at high latitudes.
Degredation. For numerous reasons, solar panels degrade with time, mostly due to physical wearing (broken cells, wiring, hazing of panels, stone and hail damage, etc.) When nominal output falls to about 85% new, panels are deemed due for replacement. This is about 20 years based on multiple studies. So you're replacing 5% of your stock every year, and losing a few percent of output.
Inverter losses. Converting panel (DC) to transmission (AC) power costs about 10%.
Transmission losses. Another 6% or so for high-voltage transmission.
Multiply all that out, and your 1 kW/m^2 * 0.17 * 0.50 * 0.9 * 0.9 * 0.25 leaves you with 17 watts of 24/7/365 capacity per square meter. Or about 1.7% net efficiency.
This doesn't account for storage which can cut into that some more.
Insolation: 1 kW/m^2
Panel efficiency: 10-20%, nominally 17%. Maximum for a single-layer cell is 37% for quantum physics reasons, with an "infinite" layer panel, 87%.
Capacity factor is the amount of time a panel actually recieves sunlightlight. Typically 20-30%, with 30% as a peak.
Spacing factor. PV doesn't work if shaded -- the entire circuit cuts out. So you have to angle and space your panels. On net, this reduces availble area by about 50%. Less near the equator, more at high latitudes.
Degredation. For numerous reasons, solar panels degrade with time, mostly due to physical wearing (broken cells, wiring, hazing of panels, stone and hail damage, etc.) When nominal output falls to about 85% new, panels are deemed due for replacement. This is about 20 years based on multiple studies. So you're replacing 5% of your stock every year, and losing a few percent of output.
Inverter losses. Converting panel (DC) to transmission (AC) power costs about 10%.
Transmission losses. Another 6% or so for high-voltage transmission.
Multiply all that out, and your 1 kW/m^2 * 0.17 * 0.50 * 0.9 * 0.9 * 0.25 leaves you with 17 watts of 24/7/365 capacity per square meter. Or about 1.7% net efficiency.
This doesn't account for storage which can cut into that some more.