Governments are finding its modular, decentralized character ideal for filling the electric needs of the thousands of remote villages in their countries. Solar energy may have had great potential , but it was left on the backburner whenever fossil fuels were more affordable and available. For instance, the US Department of Energy funded the installation and testing of over 3,000 PV systems during the 1973-1974 oil embargo. Solar energy improvements were again sought during the Gulf War in the 1990s. William Lord We still use solar power in the same two forms today, thermal and photovoltaic.
Electricity is generated when the heated fluid drives turbines or other machinery.
The second form of solar power produces electricity directly without moving parts. Today's photovoltaic system is composed of cells made of silicon, the second most abundant element in the earth's crust. Power is produced when sunlight strikes the semiconductor material and creates an electric current. The smallest unit of the system is a cell. Cells wired together form a module, and modules wired together form a panel.