# how can energy be measured Kilowatthours (kWh)

• ### How do you measure energy expenditure?

• Energy expenditure can be measured using one of the three approaches: 1. In indirect calorimetry, oxygen consumption and/or carbon dioxide production is measured and converted to energy expenditure using formulae1,2. 2. In direct calorimetry, the rate of heat loss from the subject to the calorimeter is measured.

• ### Which unit is used to measure energy?

• A calorie is a unit that is used to measure energy. The Calorie you see on a foodpackage is actually a kilocalorie, or 1,000 calories. A Calorie (kcal) is the amount of energyneeded to raise the temperature of 1 kilogram of water 1 degree Celsius.

• ### Why is energy measured in kilowatt hours?

• Once energy sources have gone through the needed combustion, transformation, or conversion to be used by us in our homes, it鈥檚 measured in kilowatt hours. Going back to the SI energy derived units, remember that a Watt is the unit of measurement for power. A kilowatt-hour is a measure of energy, which has been converted.

• ### Why is energy measured in BTUs?

• Because a Btu is so small, energy is usually measured in millions of Btus. 1 Btu = the amount of energy required to increase the temperature of one pound of water (which is equivalent to one pint) by one degree Fahrenheit. This is roughly the heat produced from burning one match.