The rays of sunlight reaching the earth contain small packets of stored energy called 'photons'.Unleashing the energy in the photons and producing Electricity is the essence of Photovoltaic technology. The two predominant P V technologies are Flat plate crystalline silicon and Thin film. Crystalline silicon technology is the 'most mature' and has been in service for more than three decades and has proved it's durability.Thin film technology though of recent origin is also gaining a market foothold.
The efficiency of crystalline technology is between 14 to 17% and that of thin film ranges from 6 to 8%. However the loss in performance due to elevated cell temperature in thin film is half of that in crystalline silicon and hence using thin film modules at sites located in the coastal areas which are hot and humid will be more advantageous.
In photovoltaics the focus is on “Energy” rather than on “Power” as in conventional power generation technologies ie on kWh and not on kW, thus selection of good quality modules, inverter (which is the heart of the SPV Power Plant) and balance of system components, coupled with robust system design will pay off in the long run as SPV Power Plants have a life span of 25 years.