What is a measurement of heat energy?

The measurement of heat energy is accurately represented by the British Thermal Unit, or BTU. A BTU is defined as the amount of heat required to raise the temperature of one pound of water by one degree Fahrenheit. This makes it a direct measurement of thermal energy and is commonly used in various heating and cooling applications, particularly in the fields of HVAC and energy management.

While Kelvin is a unit of temperature, Joules measure energy in a broader context, including mechanical and electrical energy. Calories also denote a measurement related to heat, specifically the amount of heat needed to raise the temperature of one gram of water by one degree Celsius, but it is less commonly used in practical applications related to heating systems compared to BTUs. Therefore, in the context of heat energy in practical applications, the British Thermal Unit is the most appropriate measurement.