How to Calculate Server Heat Dissipation (BTU/h) | Starline - Starline Computer: Storage und Server Lösungen von erfahrenen Experten

Energy is the ability to do work

Servers and storage systems also require energy for the semiconductors (CPUs, transistors and voltage regulators) installed in them to function. Depending on their efficiency, the systems inevitably emit heat. In the server housing itself, fans usually do the work of transporting heat.

However, the entire server enclosure or server room must also be taken into account so that the heat does not build up there. Suitable measures must therefore be taken to dissipate this energy. This can be done by ventilation or by using an air conditioning system.

But how much heat do such systems actually generate?

From BTU, Joules and kWh

Energy is usually expressed in joules, newton metres or kilowatt hours. In the field of IT, BTU (British Thermal Unit) has become established and is historically used in energy generation as well as in the heating and air conditioning industry.

This unit describes the amount of heat required to heat a British pound of water by 1 degree Fahrenheit. It was therefore chosen in a similar way to the outdated unit calorie. (One calorie heats 1 gram of water by 1 degree centigrade).

One BTU equals

1055 Joules
1055 Newton metres
0.00029 Kilowatt hours

How many BTU per hour does my server generate?

The easiest way to estimate your cooling requirements is to start at the beginning of the chain: With the power supply units of your IT system.

Example: A server with an 800 W power supply unit under full load.

As the input power of a power supply unit also depends on its efficiency, this must be taken into account when calculating the BTU/h value. Therefore, divide the wattage of the power supply unit by its efficiency from the product specifications.

For a server with two redundant power supply units, only use the output of one power supply unit for the calculation, as one power supply unit is sufficient to supply the server in the event of a fault. The power supply unit of the example server has an efficiency of 89 %.

Input power: 800 W / 0.89 = 899 W

Now multiply this power by a factor of 3.412 to obtain BTU/h. (The factor 3.412 results from the unit conversion: 1 W x 3,600 s/h / 1,055 J/BTU)

In our example it is:

899 W x 3.412 BTU/Wh = 3,067 BTU/h

Proceed accordingly with all other systems that are installed in the rack or in the entire server room and add these energy quantities together. This is how you finally arrive at the amount of heat generated by your system.

A cooling system must therefore be dimensioned large enough to be able to dissipate this full-load heat.

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Konrad Beyer

Technical Support

Our technical manager has a comprehensive knowledge of all storage and server topics.

Calculate server heat output