Kilowatt-hour (unit kWh) – Energy Unit

Energy is generally defined as the potential to do work or produce heat. This definition causes the SI unit for energy to be the same as the unit of work – the joule (J). Joule is a derived unit of energy, and it is named in honor of James Prescott Joule and his experiments on the mechanical equivalent of heat. In more fundamental terms, 1 joule is equal to:

1 J = 1 kg.m2/s2

Since energy is a fundamental physical quantity and is used in various physical and engineering branches, there are many energy units in physics and engineering.

Kilowatt-hour (unit: kWh)

Kilowatt-hour (unit: kWh). Kilowatt-hour is a derived unit of energy. It is used to measure energy, especially electrical energy in commercial applications. One kilowatt-hour equals one kilowatt of power produced or consumed for one hour (kilowatts multiplied by the time in hours). Electric utilities commonly use the kilowatt-hour as a billing unit for energy delivered to consumers. 1kW . h = 1kW . 3600s = 3600kWs = 3600kJ = 3600000J. One kilowatt-hour corresponds to the heat required to evaporate 1.58 kg of liquid water at 100°C. A 100-watt radio that operates for 10 hours continuously consumes one kilowatt-hour.

    • 1 kWh = 3.6 x 106 J
    • 1 kWh = 8.6 x 105 cal
    • 1 kWh = 3412 BTU

conversion - joule, calorie, kilowatthour - energy units

 
References:
Reactor Physics and Thermal Hydraulics:
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  5. Todreas Neil E., Kazimi Mujid S. Nuclear Systems Volume I: Thermal Hydraulic Fundamentals, Second Edition. CRC Press; 2 edition, 2012, ISBN: 978-0415802871
  6. Zohuri B., McDaniel P. Thermodynamics in Nuclear Power Plant Systems. Springer; 2015, ISBN: 978-3-319-13419-2
  7. Moran Michal J., Shapiro Howard N. Fundamentals of Engineering Thermodynamics, Fifth Edition, John Wiley & Sons, 2006, ISBN: 978-0-470-03037-0
  8. Kleinstreuer C. Modern Fluid Dynamics. Springer, 2010, ISBN 978-1-4020-8670-0.
  9. U.S. Department of Energy, THERMODYNAMICS, HEAT TRANSFER, AND FLUID FLOW. DOE Fundamentals Handbook, Volume 1, 2, and 3. June 1992.

See above:

Energy