Btu (I.T., pre-1956)
The Btu (I.T., pre-1956) refers to the International Table Btu, a specific definition used before 1956. It represents the amount of heat required to raise the temperature of one pound of water by one degree Fahrenheit at a constant pressure of one atmosphere.
Megawatt-hours
A megawatt-hour (MWh) is the amount of energy consumed when one megawatt (MW) of power is used for one hour. It is used to measure large-scale energy production or consumption such as power plants.