Calories (thermoc.)
A thermochemical calorie (cal_th) is defined as exactly 4.184 joules. It is roughly the energy needed to warm one gram of water by one degree Celsius.
Kilowatt-hours
A kilowatt-hour (kWh) is the amount of energy when a power of one kilowatt (1,000 watts) is used continuously for one hour. Utility companies often bill consumers based on the number of kilowatt-hours consumed.