Electricity producers include power plants of all types. They can be assigned to specific energy conversion processes. For example, power generation from kinetic energy, from thermal energy, from chemical energy through the combustion of coal, natural gas or crude oil, and from nuclear energy. In addition, there are power plants based on renewable energy sources. These include solar energy, wind energy, hydroelectric power, biomass and geothermal energy. The above-mentioned energy sources are playing an increasingly important role in energy planning, which envisages a reduction in carbon dioxide emissions.