hp·h

horsepower-hour

Energyexact by definition

The horsepower-hour is the work done by one mechanical horsepower running for an hour, exactly 2,684,519.537696172 joules, or about 2.68 MJ. It is the traditional unit of engine and machine work output, and it still appears in fuel consumption figures as pounds of fuel per horsepower-hour.

Watch out: It is built on the mechanical horsepower of 550 ft·lbf/s. Built on the metric horsepower it would be 2.648 MJ, and on the electrical horsepower 2.686 MJ. Brake specific fuel consumption figures are only comparable when the horsepower behind them is the same one.

1 hp·h 2,684,519.5 J