How Thermal Electric Power Plants Work

All thermal electric power plants work in a somewhat similar manner regardless if powered by: coal; natural gas; other fossil fuels; biomass; nuclear or geothermal energy.  Heat (energy) is used to boil water creating super-heated steam.  This pressurized steam is then run through a turbine.  Most of the pressure in the steam is converted to mechanical energy as it flows through and turns the turbine.  The spinning turbine is connected to an electrical generator, which converts the rotating mechanical energy to electricity (electrical energy).  The low pressure steam is condensed back to water, then recycled to be heated up again into steam.

Power plants that burn fossil fuels or biomass expel CO2 (carbon dioxide) into the air, which is considered by many to be a leading cause of global warming and has been the subject of a considerable amount of debate.  Several different means of scrubbing smoke stacks of CO2 and other gases have been considered, but are quite expensive.  Since green plants are a natural user of CO2, a potentially more sustainable method of removing CO2 from smoke stacks is to pipe it into conventional greenhouses, hydroponics greenhouses, or algae bioreactors.  

In most cases the waste heat from the condensers is expelled into the atmosphere, or into bodies of water.  In a few cases it is used to heat buildings (during the winter in northern climates).  If green plants are used to remove CO2, then the waste heat could be used to heat the greenhouses or bioreactors!  Waste heat can also be used for air conditioning in a process called absorption refrigeration, where heat is used to run the refrigeration system instead of electricity.