5. Glossary

Energy; anergy

Complement to exergy to form the energy of a system. It is directly linked to entropy by its product with the ambient temperature.

Capacité thermique; heat capacity

The ability of a system to store a certain amount of heat either at a constant volume or under constant pressure.

Latent heat; Chaleur latente

Quantity of heat absorbed by a fluid at constant temperature to change its physical state, pressure or volume. It is generally defined in terms of a unit of mass.

Coefficient of performance

For a thermal generator, the ratio between the heat supplied to the hot well in the case of a heat pump, or received from the cold source in the case of a refrigeration machine, and the energy used.