Horsepower Hour Joule BTUCalorieERGeVFoot-poundGasolineGigajouleHorsepower HourInch-poundJouleKilojouleKilocalorieKilowatt HourMegajoulePetajouleTerajouleThermWatt SecondWh BTUCalorieERGeVFoot-poundGasolineGigajouleHorsepower HourInch-poundJouleKilojouleKilocalorieKilowatt HourMegajoulePetajouleTerajouleThermWatt SecondWh How many Joules in a Horsepower Hour? 1 Horsepower Hour equals to 2684520 Joules