Around 30% of the power used in a server room goes on the cooling system
Server rooms need to be kept cool because components such as CPUs and disk drives produce a considerable amount of heat which, if it is not ducted out of the room, can damage the equipment. Be on your guard for inefficient and expensive solutions.
Cooling function
The function of a cooling system is to keep vital parts of the equipment cool. These include: CPUs, disk drives, UPS batteries and other devices. Cooling accounts for 30% of the total energy consumption of a server room.
Reduce electricity consumption for cooling by blowing in cold air
A temperature of 25-26 °C is sufficient if cold air is ducted directly to CPUs, disk drives and other devices. If the cold air is mixed with warm air on its way to the equipment, it will be necessary to lower the air temperature produced by the cooling system, which in turn increases the electricity used for cooling.
Power consumption rises by 1-3% for every degree that the temperature is reduced.
Avoid liquid cooling systems
Smaller server rooms are often cooled with small liquid cooling systems that function as air conditioning units. Technically speaking, this is a very poor solution because the cold air from the cooling system is mixed with the warm air in the room before the cool air reaches the CPUs, disk drives, etc.
Free cooling using external air
In Denmark, where the temperature is under 20 °C for most of the year, you can blow cold external air through the server room instead of cooling it using electricity. In summer, the weather can be too warm for free cooling so it’s not possible to completely avoid using a cooling system.
Read more about cooling in ‘Projekteringsvejledning for energieffektive serverrum’ (Planning guidelines for energy efficient server rooms) (in Danish)
Page last updated 06.10.2008