What does solar cell efficiency or power mean?
The power (the product of current and voltage) of a solar cell is temperature-dependent. Higher cell temperatures result in lower power output and thus in lower efficiency. The efficiency figure (or cell efficiency) states how much of the insolation is converted into available electrical power. The higher the efficiency of a cell, the better its capability to convert radiant light into electric power. The higher the efficiency, the more power is generated by a given area of solar panels. Thus a solar module with an efficiency of 12.5% generates 125 watts of peak power per square metre. If the efficiency is 10%, 100 watts of peak power is generated (under standard test conditions with 1000 watt insolation per square metre). In other words, the first module produces 25% more solar power per annum with the same size of installation.
