Operation of power plants
Energy is generated in power plants so that the burning flame and the resulting hot flue gases heat up the water flowing in the pipes on the walls of the steam boiler, and this water becomes vaporised. The resulting water vapour makes the rotor of the steam turbine rotate when it travels through the blades connected to the turbine shaft. The energy from the rotating movement is converted into electric energy in the generator, which is connected to the same shaft as the turbine.
High efficiency
The steam that has travelled through the turbine still contains plenty of heat energy. Steam is condensed, i.e. converted back into water by cooling it with district heating water, which, in turn, is utilised when buildings are heated with district heat. The recovered heat raises the efficiency of the power plant to up to 92 per cent.
Emissions under control
Russian natural gas, which is used as energy in natural gas-fired power plants, consists almost exclusively of coal and hydrogen, producing carbon dioxide and water under combustion. Nitrogen emissions causing acid rain account for one-sixth of the nitrogen emissions of the coal-fired power plant, and there are no sulphur or dust emissions.
Due to the efficient desulphurisation plant, new burners and electrostatic precipitator (i.e. flue gas ash separator) in coal-fired power plants, Helsingin Energia’s plants keep well below the emission limits imposed by the authorities.