Megawatt

Conventions in the electric power industry

In the electric power industry, megawatt electrical (MWe or MW_e) refers by convention to the electric power produced by a generator, while megawatt thermal or thermal megawatt (MWt, MW_t, or MWth, MW_th) refers to thermal power produced by the plant and megawattmechanical (MW_m) to mechanical power. For example, the Embalse nuclear power plant in Argentina uses a fission reactor to generate 2,109 MW_t (i.e. heat), which creates steam to drive a turbine, which generates 648 MW_e (i.e. electricity). Other SI prefixes are sometimes used, for example gigawatt electrical (GW_e). The International Bureau of Weights and Measures, which maintains the SI-standard, states that further information about a quantity should not be attached to the unit symbol but instead to the quantity symbol (e.g., P_th = 270 W rather than P = 270 W_th) and so these unit symbols are non-SI. In compliance with SI, the energy company Ørsted A/S uses the unit megawatt for produced electrical power and the equivalent unit megajoule per second for delivered heating power in a combined heat and power station such as Avedøre Power Station.