# Convert Watt to Btu (IT)/hour

Please provide values below to convert watt [W] to Btu (IT)/hour [Btu/h], or *vice versa*.

### Watt

**Definition:** A watt (Symbol: W) is the SI (International System of Units) derived unit of power. It is defined as 1 joule per second and is used to quantify the rate of energy transfer.

**History/origin:** The watt is named after James Watt, a Scottish inventor. It was first proposed in 1882 by William Siemens who defined it as "the power conveyed by a current of an Ampere through the difference of potential of a Volt." This was the definition used at the time within the existing system of units. In 1908, the "international" definitions were defined, with Siemens' definition being adopted as the international watt. These were used until 1948 when the General Conference on Weights and Measures re-defined the watt to absolute units, using only mass, time, and length. 1 absolute watt is equal to 1.00019 international watts. The absolute watt was adopted as the SI unit of power in 1960.

**Current use:** As the SI derived unit of power, the watt in all its multiples and submultiples is used in many applications worldwide from radio transmission to use in the electric power industry. The watt as a unit of power should not be confused with its energy counterpart, the watt-hour (and all its multiples/submultiples).

### British thermal unit per hour

**Definition:** The British thermal unit per hour (symbol: Btu/h) is a United States customary system unit of power. This unit is often abbreviated as simply "Btu," which is the same abbreviation used for British thermal units, a measurement of heat. One watt, the International System of Units derived unit of power, is equal to approximately 3.41214 Btu/h.

**History/origin:** The British thermal unit per hour is based on the British thermal unit (symbol: Btu or BTU), a traditional United States customary unit of heat, where heat is a type of energy transfer in which energy moves from a hotter to a colder substance. The BTU is specifically defined as the amount of heat required to increase the temperature of one pound of water by one °F. It has a number of different definitions all of which equate to approximately 1,055 joules.

**Current use:** The British thermal unit per hour is not a widely used unit. Multiples of the watt hour, often the kilowatt hour, are more frequently used than Btu/h, even in the United States.

### Watt to Btu (IT)/hour Conversion Table

Watt [W] | Btu (IT)/hour [Btu/h] |
---|---|

0.01 W | 0.0341214163 Btu/h |

0.1 W | 0.3412141633 Btu/h |

1 W | 3.4121416331 Btu/h |

2 W | 6.8242832663 Btu/h |

3 W | 10.2364248994 Btu/h |

5 W | 17.0607081656 Btu/h |

10 W | 34.1214163313 Btu/h |

20 W | 68.2428326626 Btu/h |

50 W | 170.6070816564 Btu/h |

100 W | 341.2141633128 Btu/h |

1000 W | 3412.1416331279 Btu/h |

### How to Convert Watt to Btu (IT)/hour

1 W = 3.4121416331 Btu/h

1 Btu/h = 0.2930710702 W

**Example:** convert 15 W to Btu/h:

15 W = 15 × 3.4121416331 Btu/h = 51.1821244969 Btu/h