Kilowatt-hours to Gigajoules conversion

What is kilowatt-hours?

A Kilowatt-hour is a unit of energy and its units, kWh, are formed with W for watt and h for hour from SI unit system combined with letter k, metric prefix, for 1,000 or $10^3$. Its definition, in the context of electricity, is the energy of one watt power flowing for one hour.

Followings equivalent equations are identical but in different units. Please note that factor $10^3$ is representing Kilo prefix in kWh unit.

$$1 kWh = 10^3*Pt = 10^3*IVt = 3600 * 10^3*J = 2.247 * 10^{22} * 10^3 eV = 8.598*10^5 * 10^3 cal$$

$P - Power$
$t - Time \text{ (in hours. Multiply by 3600 to convert to seconds)}$
$I - Current$ $V - Volts$
$J - Joules$
$eV - Electronvolt$
$cal - Calories$

Wikipedia page for Kilowatt-hour (watt-hour redirected to kWh) UCI article on Energy Units and Conversions Ian Woofenden's explanation on difference between Watts and Watt-Hours

What is gigajoules?

A gigajoule (GJ) is a unit of energy, specifically a large unit of measurement for electrical and thermal energy.

One gigajoule is equal to one billion joules. To put that in perspective:

• 1 joule is the amount of energy required to lift an object weighing about 2 pounds up 3 feet.
• 1 megajoule (MJ) is equal to 1 million joules, which is a significant amount of energy but still relatively small compared to what we use on a daily basis.
• 1 gigajoule (GJ), on the other hand, is equivalent to:
  • About 277.8 kilowatt-hours (kWh) or 0.2778 megawatt-hours (MWh).
  • The energy produced by burning about 200 kilograms (440 pounds) of gasoline.
  • Enough electricity to power a typical household for about 24 hours.

Gigajoules are often used in the context of:

• Energy production and consumption (e.g., electrical power plants, oil refineries)
• Thermal energy storage (e.g., large-scale heat pumps, industrial processes)
• Renewable energy sources (e.g., solar panels, wind turbines)

I hope that helps you understand gigajoules better!