Board of Trade Unit

The Board of Trade Unit or B.O.T.U. is a non-metric unit of electrical energy, defined by a former department of the UK government. It is the same as the kilowatt-hour (kWh), which is the amount of energy consumed by a one-kilowatt appliance in one hour.

One B.O.T.U. or kWh = 3.6 × 10⁶ joule.

The B.O.T.U. should not be confused with the British thermal unit or Btu, which is a much smaller quantity of thermal energy.