The unit is most often used as a measure of power (as Btu/h) in the power, steam generation, heating and air conditioning industries, and also as a measure of agricultural energy production (Btu/kg).
The unit is most often used in the power, steam generation, heating and air conditioning industries. In scientific contexts the Btu has largely been replaced by the SI unit of energy, the joule, though it may be used as a measure of agricultural energy production (Btu/kg).