The primary source of energy in the 20th century was based on fossil fuels. The burning of the fossil fuels led to the large CO2 concentration in the atmosphere effecting our climate. On the other hand fossil fuels are a limited resource and a different solution has to be found for the energy source.

In the 21st century renewable, clean, solar energy will take over the role of fossil fuels.

The figures above show the forecast of the gros of renewable energy in the 21st century. The curve on the left in red on a logaritmic scale is the cumulative installed electricity forecast. The green next to it on a lineal scale the annual installed capacity.

As of 2018, 400 GW cumulative SPV electricity has been installed worldwide. Before the end of the 21st century most of fossil fuel generation of electricity is expected to be replaced by clean, renewable SPV generated electricity. The 400 GW of cumulative SPV electricity installed is expected to increase to over 200.000 GW. See the graph above. The S curve shows annual production of 5000 GW by the end of the century.