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Contents
How many BTUs is a joule?
The modern SI unit for heat energy is the joule (J); one BTU equals about 1055 J (varying within the range 1054–1060 J depending on the specific definition; see below).
What is the equivalent value of 1 BTU to joule J )?
Energy (BTUIT) | Energy (J) |
---|---|
1 BTU | 1055.055853 J |
2 BTU | 2110.111705 J |
3 BTU | 3165.167558 J |
4 BTU | 4220.223410 J |
How many joules are in a Watt?
Power in general is defined as energy over time. Watts are defined as 1 Watt = 1 Joule per second (1W = 1 J/s) which means that 1 kW = 1000 J/s.
How many BTU are in a kW?
This means that 1 kW is equal to 3412 BTU/h.
What does it mean 12000 BTU?
BTU tells you how much energy your air conditioner is using to do all that. So, if you see that your air conditioner has 12,000 BTUs, that means it’s absorbing 12,000 British Thermal Units of heat each hour and moving it outside so your environment inside feels better.
How do you calculate BTU?
…
BTU Requirements Based On Room Size (By Energy Star)
Cooling Area (In Square Feet): | BTU Cooling Capacity: |
---|---|
1,500 to 2,000 square feet | 30,000 BTU |
2,000 to 2,500 square feet | 34,000 BTU |
How much energy is a BTU?
One British thermal unit (Btu) is approximately equal to the energy released by burning a match. A single Btu is very small in terms of the amount of energy a single household or an entire country uses. In 2021, the United States used about 97.33 quadrillion Btu of energy.
How many watts are in a BTU?
BTUs/h are normally used in the definition of the cooling power of air conditioning systems as well as of the heating power of fuel. For W to BTU/h conversions, 1 W is equal to 3.41 BTU/h.
What is joules equal to?
1 Joule (J) is the MKS unit of energy, equal to the force of one Newton acting through one meter. 1 Watt is the power of a Joule of energy per second. Power = Current x Voltage (P = I V)
How many joules are in a gallon of gas?
A gallon of gasoline contains approximately 132×106 joules of energy, equivalent to 125,000 British thermal units or 36,650 watt hours.
How much is 1000 joules in watts?
Energy in Joules (J) | Time in seconds | Power in watts (W) |
---|---|---|
200 joules to watts | 35 | 5.71 |
300 joules to watts | 40 | 7.5 |
600 joules to watts | 45 | 13.33 |
1000 joules to watts | 50 | 20 |
How many joules is 1000 watts?
A kilowatt is equal to 1000 watts, so 1 kWh represents the amount of energy transfer that occurs over one hour from a power output of 1000 watts (i.e., joules per second). Thus 1 kWh is equal to 3,600,000 joules of energy transfer (work).
How many kWh of energy is in 2 BTU?
Energy (BTU) | Energy (kWh) |
---|---|
1 BTU | 0.000293 kWh |
2 BTU | 0.000586 kWh |
3 BTU | 0.000879 kWh |
4 BTU | 0.001172 kWh |
Is BTU a power or energy?
The British Thermal Unit (BTU or Btu) is commonly used to describe the energy content of fuels and the power of heating and cooling systems. One BTU is the amount of energy required to raise the temperature of one pound of water by one degree Fahrenheit.
How many watts is a 18000 BTU air conditioner?
A 1-ton air conditioner (18,000 BTU) with a 10 EER rating has a 1,800 wattage. That means that a 2-ton AC has a 2,000W wattage.
How many watts are in a BTU?
BTUs/h are normally used in the definition of the cooling power of air conditioning systems as well as of the heating power of fuel. For W to BTU/h conversions, 1 W is equal to 3.41 BTU/h.
How many joules are in a MJ?
One megajoule is equal to 1,000,000 joules, which are the energy equal to the force on an object of one newton at a distance of one meter. The megajoule is a multiple of the joule, which is the SI derived unit for energy.
What units are BTU?
A British thermal unit (Btu) is a measure of the heat content of fuels or energy sources. It is the quantity of heat required to raise the temperature of one pound of liquid water by 1 degree Fahrenheit at the temperature that water has its greatest density (approximately 39 degrees Fahrenheit).
Is BTU a power or energy?
The British Thermal Unit (BTU or Btu) is commonly used to describe the energy content of fuels and the power of heating and cooling systems. One BTU is the amount of energy required to raise the temperature of one pound of water by one degree Fahrenheit.
British thermal unit – Wikipedia
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Electricity and Energy Terms In Lighting (J, kW, kWh, Lm/W)
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BTU/h To kW Air Conditioning Calculator (Simple Converter)
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BTU to Joules Conversion (BTU to J) – Inch Calculator
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Convert Btu to joule – Conversion of Measurement Units
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British thermal unit – Wikipedia
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BTU to Joules – convert BTU to J
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British thermal unit
Unit of energy
“BTU” redirects here. For other uses, see BTU (disambiguation)
The British thermal unit (BTU or Btu) is a unit of heat; it is defined as the amount of heat required to raise the temperature of one pound of water by one degree Fahrenheit. It is also part of the United States customary units.[1] The modern SI unit for heat energy is the joule (J); one BTU equals about 1055 J (varying within the range 1054–1060 J depending on the specific definition; see below).
While units of heat are often supplanted by energy units in scientific work, they are still used in some fields. For example, in the United States the price of natural gas is quoted in dollars per the amount of natural gas that would give 1 million BTUs of heat energy if burned.[2][3]
Definitions [ edit ]
A BTU was originally defined as the amount of heat required to raise the temperature of 1 avoirdupois pound of liquid water by 1 degree Fahrenheit at a constant pressure of one atmospheric unit.[4] There are several different definitions of the BTU that differ slightly. This reflects the fact that the temperature change of a mass of water due to the addition of a specific amount of heat (calculated in energy units, usually joules) depends slightly upon the water’s initial temperature. As seen in the table below, definitions of the BTU based on different water temperatures vary by up to 0.5%.
Variant Energy (J) Notes Thermochemical ≈1,054.35[a] Originally, the thermochemical BTU was defined as the heat required to raise the temperature of one pound of water from its freezing point to its boiling point, divided by the temperature difference (180 °F). The basis for its modern definition in terms of SI units is the similar, thermochemical calorie, which was originally defined as the heat required to raise the temperature of one gram of water from freezing to boiling divided by the temperature difference in Celsius (100 °C). The International Standards Organization now defines the thermochemical calorie as exactly 4.184 J.[4] The thermochemical BTU is then defined using the conversions from grams to pounds and from Celsius to Fahrenheit.[5] 59 °F (15.0 °C) ≈1,054.80[6] Used for American natural gas pricing.[3] 60 °F (15.6 °C) ≈1,054.68[7] Mainly Canadian.[ citation needed ] 39 °F (3.9 °C) ≈1,059.67[7] Uses the calorie value of water at its maximum density (4 °C, 39.2 °F).[ citation needed ] IT ≈1,055.06[b] An early effort to define heat units directly in terms of energy units, and hence to remove the direct association with the properties of water, was taken by the International Steam Table Conferences. These conferences originally adopted the simplified definition that 860 “IT” calories corresponded to exactly 1 international watt-hour (not the same as a modern watt-hour). This definition ultimately became the statement that 1 IT calorie is exactly 4.1868 J.[4][8] The BTU is then calculated from the calorie as is done for the thermochemical definitions of the BTU and the calorie, as in International standard ISO 31-4 Quantities and units—Part 4: Heat and British Standard BS 350:Part 1:1974 Conversion factors and tables.[5][9][10]
Prefixes [ edit ]
Units kBtu are used in building energy use tracking and heating system sizing. Energy Use Index (EUI) represents kBtu per square foot of conditioned floor area. “k” stands for 1,000.
The unit Mbtu is used in natural gas and other industries to indicate 1,000 BTUs.[11][12] However, there is an ambiguity in that the metric system (SI) uses the prefix “M” to indicate one million (1,000,000). Even so, “MMbtu” is often used to indicate one million BTUs particularly in the oil and gas industry.[13]
Energy analysts accustomed to the metric “k” for 1,000 are more likely to use MBtu to represent one million, especially in documents where M represents one million in other energy or cost units, such as MW, MWh and $.
The unit therm is used to represent 100,000 BTUs.[11] A decatherm is 10 therms or one MMBtu (million Btu). The unit quad is commonly used to represent one quadrillion (1015) BTUs.[13]
Conversions [ edit ]
One Btu is approximately:
A Btu can be approximated as the heat produced by burning a single wooden kitchen match or as the amount of energy it takes to lift a one-pound (0.45 kg) weight 778 feet (237 m).[14]
For natural gas [ edit ]
In natural gas pricing, the Canadian definition is that 1 000 000 Btu ≡ 1.054 615 GJ . [15]
≡ . The energy content (high or low heating value) of a volume of natural gas varies with the composition of the natural gas, which means there is no universal conversion factor for energy to volume. 1 cubic foot (28 litres) of average natural gas yields ≈ 1030 Btu (between 1010 Btu and 1070 Btu, depending on quality, when burned)
As a coarse approximation, 1,000 cubic feet (28 m 3 ) of natural gas yields ≈ 1 000 000 Btu ≈ 1 GJ .
) of natural gas yields ≈ ≈ . For natural gas price conversion 1000 m3 ≈ 36.9 million Btu and 1 000 000 Btu ≈ 27.1 m3
The SI unit of power for heating and cooling systems is the watt. Btu per hour (Btu/h) is sometimes used in North America and the United Kingdom – the latter for air conditioning mainly, though “Btu/h” is sometimes abbreviated to just “Btu”.[16] MBH—thousands of Btus per hour—is also common.[17]
1 W is approximately 3.412142 Btu/h [18]
1,000 Btu/h is approximately 0.2931 kW
1 hp is approximately 2,544 Btu/h
Associated units [ edit ]
1 ton of cooling , a common unit in North American refrigeration and air conditioning applications, is 12,000 Btu/h (3.52 kW). It is the rate of heat transfer needed to freeze 1 short ton (907 kg) of water into ice in 24 hours.
, a common unit in North American refrigeration and air conditioning applications, is 12,000 Btu/h (3.52 kW). It is the rate of heat transfer needed to freeze 1 short ton (907 kg) of water into ice in 24 hours. In the United States and Canada, the R-value that describes the performance of thermal insulation is typically quoted in square foot degree Fahrenheit hours per British thermal unit (ft 2 ⋅°F⋅h/Btu). For one square foot of the insulation, one BTU per hour of heat flows across the insulator for each degree of temperature difference across it.
⋅°F⋅h/Btu). For one square foot of the insulation, one BTU per hour of heat flows across the insulator for each degree of temperature difference across it. 1 therm is defined in the United States and European Union as 100,000 Btu—but the U.S. uses the Btu 59 °F while the EU uses the Btu IT . United Kingdom regulations were amended to replace therms with joules with effect from 1 January 2000. [19] As of 2013 the therm is still used in natural gas pricing in the United Kingdom. [20]
is defined in the United States and European Union as 100,000 Btu—but the U.S. uses the Btu while the EU uses the Btu . United Kingdom regulations were amended to replace therms with joules with effect from 1 January 2000. As of 2013 the therm is still used in natural gas pricing in the United Kingdom. 1 quad (short for quadrillion Btu) is 1015 Btu, which is about 1 exajoule ( 1.055 × 1018 J ). Quads are used in the United States for representing the annual energy consumption of large economies: for example, the U.S. economy used 99.75 quads in 2005.[21] One quad/year is about 33.43 gigawatts.
The Btu should not be confused with the Board of Trade Unit (BTU), an obsolete UK synonym for kilowatt hour (1 kW⋅h or 3,412 Btu).
The Btu is often used to express the conversion-efficiency of heat into electrical energy in power plants. Figures are quoted in terms of the quantity of heat in Btu required to generate 1 kW⋅h of electrical energy. A typical coal-fired power plant works at 10,500 Btu/kWh (3.1 kWh/kWh), an efficiency of 32–33%.[22]
The centigrade heat unit (CHU) is the amount of heat required to raise the temperature of one pound of water by one Celsius degree. It is equal to 1.8 BTU or 1,899 joules.[23] In 1974, this unit was “still sometimes used” in the United Kingdom as an alternative to BTU.[24]
Another legacy unit for energy in the metric system is the calorie, which is defined as the amount of heat required to raise the temperature of one gram of water by one degree Celsius.[25]
See also [ edit ]
Notes [ edit ]
^ 4.184 × 453.59237 × 5 ⁄ 9 ^ 4.1868 × 453.59237 × 5 ⁄ 9
BTU/h To kW Air Conditioning Calculator (Simple Converter)
The US and UK-produced air conditioners always have the same capacity unit: BTU/h or British Thermal Units.
When it comes to measuring the power (capacity) of an air conditioner, everybody else (Europeans and most of the world) use kW or kiloWatts.
The question here is obvious:
How to convert BTU to kW?
It’s quite simple. You just need to know the conversion factor between BTU/h and kW. Here is how many kW does 1 BTU/h equal to:
1 BTU = 0.00029307108333333 kW
Example: How to convert 12000 BTU to kW? Simple. Just multiply BTUs by 0.00029307108333333 kW. Result: 12000 BTU is equal to 3.52 kW.
To help you out, we have designed a BTU to kW calculator, complete with a BTU to kW chart. Further on, we also solve examples for 9000 BTU, 18000 BTU, and 24000 BTU.
We’ll look at what BTU or BTU/h (in HVAC, they are used interchangeably) and kW are. Let’s start with a simple way how to convert BTU/h to kW (just input BTU/h, and you’ll get the kW):
Convert BTU To kW (Calculator)
The key part when buying an air conditioner is to know how powerful it is. If you’re used to kW and get a BTU number, you don’t really know what the capacity is, and visa versa.
Here is the quick BTU/h to kW converter to help you choose the correct size of an air conditioner:
Further on, you will find a BTU to kW chart with calculated values of kW from 6,000 BTU/h to 60,000 BTU.
BTU and kW (Air Conditioner Capacity)
BTU stands for ‘British Thermal Unit‘. It denotes the amount of energy to raise 1 pound of water for 1 degree Fahrenheit. Honestly, this sentence makes sense only to the British.
BTU is a measure of energy, not power. To get power, we have to use some time unit as in ‘This or that air conditioner can produce 10,000 BTU of power per hour‘.
Let’s say we have an air conditioner with a capacity of 10,000 BTU. That’s a simplified description. In fact, we have an air conditioner that is capable of putting out 10,000 BTU per hour. The correct unit here is BTU/h.
kW, on the other hand, stands for kiloWatt. Watt is the basic unit of power (in the metric system Europeans use), and it’s basically the amount of power we have to give to a 1 kg object that starts moving with an acceleration of 1 m/s2. kiloWatt is just 1000 Watts. This sentence makes sense to Europeans who know a bit of physics.
For everybody who wants to see some example, here’s a convenient table:
BTU To kW Conversion Table
Here are a few standard BTU capacities converted to kW:
BTU: kW: 6000 BTU to kW: 1.76 kW 8000 BTU to kW: 2.34 kW 10000 BTU to kW: 2.93 kW 12000 BTU to kW: 3.52 kW 14000 BTU to kW: 4.10 kW 16000 BTU to kW: 4.69 kW 18000 BTU to kW: 5.28 kW 20000 BTU to kW: 5.86 kW 24000 BTU to kW: 7.03 kW 30000 BTU to kW: 8.79 kW 36000 BTU to kW: 10.55 kW 48000 BTU to kW: 14.07 kW 60000 BTU to kW: 17.58 kW
You can see that air conditioners with 3 kW have some decent power. Those with 10 kW can easily cool down a small house.
Here are some examples:
How to convert 9 000 BTU to kW? 9000 BTU is equal to 2.64 kW. How to convert 18 000 BTU to kW? 18000 BTU is equal to 5.28 kW. How to convert 24 000 BTU to kW? 24000 BTU is equal to 7.03 kW.
For people who like to have an in-depth look, here are some equations for BTU to kW conversion:
How To Calculate kW From BTU For Air Conditioners
Physicists are the ones who use the basic procedure breakdown of the BTU to kW equation. The outtakes are then used by engineers designing air conditioners and other HVAC systems. For example, it’s handy to know how many BTUs is 1 kW when comparing natural gas and electric garage heaters’ energy output.
Here is this outtake that you can always use:
3412 BTU/h = 1 kW
This means that 1 kW is equal to 3412 BTU/h. You can easily convert kW to BTU here.
Here’s a rule of thumb if you’re a European looking at a US air conditioner.
Do you see that BTU number? Let’s say it’s 10,000 BTU.
To get a kW number, divide the BTU by about 3,000. For a 10,000 BTU portable air conditioner, you’ll calculate the power to be somewhere around 3.3 kW, right? It’s 2.93 kW, to be exact, but 3.3 kW is quite a good estimate.
BTU to kW conversion applies to different types of air conditioners:
In any case, make sure that you buy a powerful-enough air conditioner to cool certain footage of your home.
BTU to Joules Conversion (BTU to J)
Enter the energy in british thermal units below to get the value converted to joules.
Do you want to convert joules to british thermal units
How to Convert British Thermal Units to Joules
To convert a british thermal unit measurement to a joule measurement, multiply the energy by the conversion ratio.
Since one british thermal unit is equal to 1,055.055853 joules, you can use this simple formula to convert:
joules = british thermal units × 1,055.055853
The energy in joules is equal to the british thermal units multiplied by 1,055.055853.
For example, here’s how to convert 5 british thermal units to joules using the formula above. 5 BTU = (5 × 1,055.055853) = 5,275.279263 J here’s how to convert 5 british thermal units to joules using the formula above.
British thermal units and joules are both units used to measure energy. Keep reading to learn more about each unit of measure.
So you have finished reading the how many joules in a btu topic article, if you find this article useful, please share it. Thank you very much. See more: J to btu, joule to btu, btu to joules explanation, what is a btu, BTU to kWh, BTU to kJ, btu to calorie, btu to megajoules