Renewable energy systems are made with a relatively small amount of materials and energy.

After a short running time a wind turbine has already recovered the energy required for its production, transport, erection and dismantling as
well as its disposal. This period is called the „energy payback period“ (amortization period). After that, each operating hour supplies „net“ clean
electricity—for at least 20 years with all renewable energy sources. A wind turbine can therefore provide 70 times more energy during its life than was expended for its manufacture. This renewable quantity of electricity replaces fossil electricity from coal and gas-fired power stations and therefore avoids their CO2 emissions.

Both the climate and the energy balance are clearly positive—unlike those of fossil fuel fired power stations. These always require an external energy supply in the form of coal, natural gas or uranium in order to convert them into electricity or heat, frequently with very poor efficiencies. Thereby greenhouse gases harmful to the climate are released.

New coal-fired power stations will also continue to harm the climate. They increase the efficiency of the conversion of coal into electricity, but they are designed for a life of at least 40 years, during which they will emit large quantities of CO2.