Even without considering the additional sustainability benefits to be achieved from the scale and efficiency of commercial data centres, or the proactive monitoring of energy usage, private data centres can potentially quadruple utilisation to 80 per cent with only a 50 per cent increase in power consumption.

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Google and Facebook operate at a Power Usage Efficiency (PUE) of 1.02-1.2, while typical enterprise datacenters operate at 1.6 or above.

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The eco-rating system assesses 15 specific criteria drawn from five general categories of sustainability attributes - attributes include the usage of environmentally preferable materials, minimization of hazardous substances, energy efficiency, responsible end-of-life treatment and environmentally-responsible manufacturing.

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