BTU per hour (BTU/h) equals approximately 0.293 watts, the standard rating unit for air conditioners, heaters, and furnaces in North America. A typical window air conditioner rated at 10,000 BTU/h can cool a 400–500 square foot room, making this unit essential for HVAC system sizing. One BTU/h equals about 0.2931 watts.

Foot-pounds per second (ft·lbf/s) equals approximately 1.356 watts, an imperial power unit occasionally used in mechanical engineering contexts. While less common than horsepower for engine ratings, it provides a direct connection between torque and rotational speed. One foot-pound per second equals about 1.356 watts or 0.00182 horsepower.