énergie utile

Traductions

• anglais

  Date : 1984

  Définition

  The energy made usefully available to the consumer in its final conversion (i.e. in its final utilisation).

  Note :

  The concept of useful energy is necessary to evaluate the energy demand of an economic system in such a way as to be independent of the mix of fuel supplies. Only in this way can the effects of changes in the fuel supply mix on the primary energy demand of the economy be measured. For example, the energy required to run a water heater will depend on the type of fuel supplied; electricity can be converted to heat at 100 per cent efficiency, whereas the use of natural gas involved flue losses. However, the useful energy requirement can be calculated from the mass of water to be heated and the required temperature rise. Knowing the efficiencies with which the various fuels can be used to perform this heating, the energy that must be supplied to the heater can be calculated. The process can be applied to the house as a whole, to a factory, or more important, to an entire energy economy. In the latter role, the method is particularly relevant to strategies for fossil fuel replacement by ambient energy sources.

  Terme :

  1. useful energy

  Terme associé :

  1. net energy