Kilotons (explosive energy)
A kiloton is a unit of measurement that quantifies the energy released in an explosion. It is the energy released by detonating 1,000 tons of TNT (trinitrotoluene). One kiloton is approximately equal to 4.184 × 1012 joules.
Btu
The British Thermal Unit (Btu) is defined as the amount of heat required to raise the temperature of one pound of water by one degree Fahrenheit. It is primarily used in the United States to describe the energy content of fuels and the power of heating and cooling systems.