BTU Per Hour to Watts (BTU/h to W)

1 BTU per hour equals 0.2930710702 watts (rounded).

1 BTU per hour = 0.2930710702 watts

How to convert BTU per hour to watts

To convert BTU per hour to watts, multiply the number of BTU per hour by 0.2930710702. The factor is rounded to 10 significant digits. To go the other way, multiply watts by 3.412141633 (rounded).

watts = BTU per hour × 0.2930710702

Example: 10 BTU per hour = 2.930710702 watts.

Several different horsepower units exist. This site lists mechanical (745.7 W), metric (735.5 W) and electrical (746 W) horsepower separately.

About these units

BTU Per Hour (BTU/h)

US & ImperialCurrent unit

About 0.293 watts. The rating of air conditioners, furnaces and heaters in the US.

Btu per hour inherits its history from the British thermal unit, which a 1942 note in the journal Nature said apparently originated in the United States and was later adopted in Great Britain. The Btu was defined as the heat needed to raise one pound of liquid water by one degree Fahrenheit at a constant pressure of one atmosphere. Because water's heat capacity varies slightly with temperature, several versions exist, differing by up to 0.5 percent, so the unit has never been quite as tidy as the joule.

Dividing it by time gives a power unit used mainly in North America for heating and cooling equipment, and in the UK mostly for air conditioning. One watt is about 3.412 Btu/h, and one horsepower is about 2,544 Btu/h. Thousands of Btu per hour are often written MBH. Air conditioning capacity is often given in tons, where one ton of cooling is 12,000 Btu/h, about 3.52 kW, the rate needed to freeze one short ton of water into ice in 24 hours.

1 BTU per hour = 0.2930710702 watts (approximately).

Sources: Wikipedia: British thermal unit; Wikipedia: Watt

Watt (W)

Metric (SI)Current unit

The SI unit of power: one joule per second. A typical LED bulb uses 5–10 W and a laptop 30–60 W.

Credit for the name goes to C. William Siemens, who proposed it in August 1882 in his presidential address to the British Association for the Advancement of Science. He chose it to honor James Watt, the Scottish inventor who in 1776 improved the Newcomen steam engine. An International Conference on Electric Units and Standards adopted Siemens' definition in London in October 1908 as the international watt. After the 1948 General Conference on Weights and Measures the unit was redefined in absolute terms, and in 1960 the 11th General Conference adopted it into the SI as the unit of power.

Today one watt is one joule per second, or equivalently one volt times one ampere. Orders-of-magnitude tables put an LED light bulb at about 7 W and an adult's basal metabolic rate at roughly 100 W. A 100 kg person climbing a 3 m ladder in 5 seconds works at about 600 W, while a laborer can sustain around 75 W over an eight-hour day. The watt measures a rate, so it says how fast energy is being used, not how much has been used in total.

The watt is the reference unit for power on this site.

Sources: Wikipedia: Watt; Wikipedia: Orders of magnitude (power)

Related conversions

See all power units.