|Solar panel efficiency defines the amount of sunlight that can be converted by the panel into usable electricity.
Solar panel efficiencies for a panel depends on the cell type, manufacturer and size of the panel. A list of solar panel efficiencies of top panel manufacturers based on cell type is given as follows:
|Type of solar panel
|Panel efficiency (%)*
|17 – 21
It is worthwhile to note that the efficiencies mentioned above are for mass-produced panels. But a lot of manufacturers have managed to obtain greater efficiencies in research labs
|A key point to be noted is that a solar panel of 1 MW with higher efficiency doesn’t generate more electricity than a 1 MW solar panel with a lower efficiency. In fact, regardless of the efficiency, a 1 MW solar panel generates the same amount of electricity. However, a high efficiency 1 MW solar panel requires less area than a 1 MW panel with a lower efficiency.
Solar panel efficiencies are provided under standard Testing Conditions (STC), which are listed below.
Standard Testing Conditions
|Incoming solar radiation (Insolation)
|Air mass ratio (AM)
AM represents a coefficient that accounts for the scattering of light as it passes through the atmosphere, and changes in sun angle that in turn affect solar radiation.