# Units of measurement

## Units of energy measurement

1 TWh = 1 terawatt hour = 1,000 GWh

1 GWh = 1 gigawatt hour = 1,000 MWh

1 MWh = 1 megawatt hour = 1,000 kWh

1 kWh = 1 kilowatt hour = 1,000 Wh

## Units of power measurement

1 MW = 1 megawatt = 1,000 kW

1 kW = 1 kilowatt = 1,000 W

When Oskarshamn 3 runs at full power, the reactor can light just over 207 million low-energy lamps with 7 W power.

## What is the difference between power and energy?

Energy and power are two different physical concepts. Power is the rate of energy transfer and describes how fast the energy transfer occurs. Energy is the product of power and time:

Energy = Power x Time

In order to maintain the balance in the system, the power of the electricity production (measured in MW) must be as large as the use of electricity (in MW). Energy expressed in MWh is what an electricity-generating plant delivers during a certain amount of time, for example during one year. The longer the time span an electricity-generating plant delivers the power produced, the more energy is delivered.