scope:

The efficiency of a power station is a measure for the quality of the conversion of heat into electrical energy. Up to now, this was mainly seen under economic aspects, because an improvement in efficiency goes hand in hand with fuel savings. Today, efficiency is an important parameter with regard to exhaust emissions, ranging from the classical air pollutants dust, sulphur dioxide, etc. all the way to emissions having an effect on the climate (particularly CO2). Smaller fuel quantities also mean smaller exhaust quantities and thus lower substance transportation under otherwise equivalent conditions. While the economic aspect is essentially the power station owner's business, emissions which affect the quality of the air and the climate are of general significance.

There are different ways of defining power station efficiency, so that it is necessary to say how efficiency is to be defined, which system it refers to and under which prerequisites it is to be measured. This standard provides appropriate rules and instructions. The standard will devote particular attention to thermal outcoupling from power stations. The standard also aims at harmonising the definitions used.

This standard applies to conventional thermal power stations which are used as units exclusively or primarily for power generation. It does not apply to backpressure systems or to power stations with a power characteristic less than 2,0, or to unit heating power stations.