The inverter is an electronic device which converts the direct current (DC) electricity that comes from the solar panels into alternating current (AC) electricity which matches the AC frequency of the power lines. The inverter also matches the AC voltage of the power lines, but sets its voltage slightly higher so that the energy from the solar cells is pumped back into the power grid. Efficiency rating for the inverter is required to calculate how much power is actually produced and fed back into the electric grid. A typical inverter has an efficiency of about 94%, so 6% of the energy produced by the solar cells is lost in this conversion process.
Inverter Efficiency – Definition, Glossary, Details – Solar Mangoadmin