Convert power units — watts, kilowatts, horsepower, BTU/hr.
| Unit | Name | Value |
|---|---|---|
| W | Watt | 0.293071 |
| kW | Kilowatt | 0.000293071 |
| MW | Megawatt | 2.93071e-7 |
| hp | Horsepower (mech) | 0.00039301462 |
Formula: Watt = BTU/hr × 0.2931
Multiply any btu/hr value by 0.2931 to get watt.
Reverse: BTU/hr = Watt × 3.412
Common btu/hr values — factor: 1 BTU/hr = 0.2931 W
| BTU/hr (BTU/hr) | Watt (W) | Context |
|---|---|---|
| 100 BTU/hr | 29.31 W | Small heater element |
| 500 BTU/hr | 146.5 W | Hair dryer low |
| 1,000 BTU/hr | 293.1 W | Small space heater |
| 3,412 BTU/hr | 1,000 W | 1 kW equivalent |
| 5,000 BTU/hr | 1,465 W | Small window AC |
| 1e+04 BTU/hr | 2,931 W | Medium window AC |
| 1.2e+04 BTU/hr | 3,517 W | 1 ton AC |
| 1.8e+04 BTU/hr | 5,275 W | 1.5 ton AC |
| 2.4e+04 BTU/hr | 7,034 W | 2 ton AC |
| 3.6e+04 BTU/hr | 1.055e+04 W | 3 ton AC |
| 6e+04 BTU/hr | 1.758e+04 W | 5 ton central AC |
| 100,000 BTU/hr | 2.931e+04 W | Home furnace |
| 500,000 BTU/hr | 146,500 W | Commercial HVAC |
| 1,000,000 BTU/hr | 293,100 W | Large industrial |
| 1.000e+09 BTU/hr | 293,100,000 W | Power plant |
1 BTU/hr = 0.2931 W. Memorize for instant estimates.
Use 0.293 as a quick mental multiplier.
Multiply result by 3.412 to recover the original BTU/hr value.
Sizes residential and commercial heating and cooling systems in BTU/hr.
Interprets AC unit capacity — '12,000 BTU/hr = 1 ton' for room sizing.
Verifies furnace and AC output ratings in BTU/hr meet local building codes.
Rates boiler output and heat exchanger capacity in BTU/hr.
Calculates heating and cooling loads for buildings in BTU/hr for ASHRAE compliance.
Selects gas appliances, furnaces, and water heaters rated in BTU/hr.
BTU/hr (British Thermal Units per hour) is the Imperial unit of power used in heating, ventilation, and air conditioning (HVAC). One BTU is the heat needed to raise 1 pound of water by 1°F; divided by an hour gives a power rate equal to 0.293071 watts.
HVAC equipment is universally rated in BTU/hr in the United States: window air conditioners range from 5,000 to 25,000 BTU/hr; central AC systems from 18,000 to 60,000 BTU/hr. Natural gas furnaces are rated in BTU/hr output.
Interesting fact: 12,000 BTU/hr = 1 'ton of refrigeration' — the cooling power needed to melt one ton of ice in 24 hours. This legacy unit still defines residential AC capacity in the US, where a 'one-ton' unit is a 12,000 BTU/hr air conditioner.
The watt (W) is the SI unit of power, defined as one joule per second. It was named after James Watt, the Scottish inventor whose improvements to the steam engine in the 1760s–1780s powered the Industrial Revolution. The unit was officially adopted by the Second Congress of the British Association for the Advancement of Science in 1882.
Watts define the power consumption of all electrical devices: a phone charger draws 5–20W, a laptop 30–65W, a microwave 800–1200W. Electrical utility systems worldwide are rated and billed based on watts and kilowatts.
Interesting fact: James Watt himself coined the term 'horsepower' to market his steam engines to mine owners — he defined it as the power needed to lift 33,000 pounds one foot in one minute. The watt was named in his honor a century after his death.
Converting btu/hr to watt is common across electrical engineering, automotive, and HVAC industries. Different sectors use different power units — watts and kilowatts in electrical systems, horsepower in automotive and industrial machinery, and BTU/hr in heating and cooling — making accurate conversion essential for international equipment specifications and cross-disciplinary engineering.
Quick reference: 5 BTU/hr = 1.465 W and 10 BTU/hr = 2.931 W. Reverse: 1 W = 3.412 BTU/hr. Exact factor: 1 BTU/hr = 0.2931 W.
All conversions use IEEE 754 double-precision arithmetic, accurate to at least 8 significant figures.