Why CO₂ data centre cooling is gaining favour

Currently, outdated all-air cooling systems are often installed in high-tech data centres. This observed trend stems most probably from a rather conservative attitude and suspicion towards new systems that are perceived to be untested and the vast consequences that the failure of such a cooling system could inflict.

However, as such suspicions are gradually wearing off, carbon dioxide is gaining favour as cooling medium for IT applications because of its key properties:

• As opposed to water cooling, CO₂ poses no danger to electrical equipment or cabling as it is electrically benign
• CO₂ has zero-ozone depleting potential combined with low toxicity
• CO₂ has seven times the cooling capacity of water per kilogramme, reducing volume flows with smaller diameter distribution pipework.

CO₂ saves space and energy

As CO₂ cooling is more efficient than air and water alternatives, the carbon footprint of IT equipment rooms can be reduced by 50 to 70%. Moreover, as equipment densities can be increased valuable space is saved.

In addition, CO₂ data centre cooling solution offer substantial energy-saving potential. For example, Trox AITCS maintains that with its CO₂OLrac blade server cooling system, which is designed to absorb the heat rejected by blade servers at the rear of the cabinet, energy costs can be reduced by up to £155,000 a year for a 1MW installation.

Other developments in CO₂ IT cooling

Two other developments in IT cooling include:

• Including a thermosyphon: A CO₂ version of the thermosyphon principle is now available in a scaleable form to provide high density (HD) cooling to a single cabinet.  
• Including a free cooling option: The CO₂ circuit is pump-less and energy efficient, particularly when combined with a free cooling primary circuit.

Bearing in mind all the above benefits of CO₂ refrigerant for high-tech IT applications, Trox AITCS expects all major organisations having an environmental agenda will opt for CO₂ IT cooling solutions.