How to stop data centres from gobbling up the world’s electricity

September 29, 2019


“The savings made by hyperscale centres can be seen in their power usage efficiency (PUE), defined as the total energy needed for everything, including lights and cooling, divided by the energy used for computing (a PUE of 1.0 would be a perfect score). Conventional data centres typically have a PUE of about 2.0; for hyperscale facilities, that’s been whittled down to about 1.2. Google, for one, boasts a PUE of 1.12 on average for all its centres.

Older or less technologically adept data centres can contain a mix of equipment that is hard to optimize — and some that is even useless. In 2017, Jonathan Koomey, a California-based consultant and leading international expert on IT, surveyed with a colleague more than 16,000 servers tucked into corporate closets and basements and found that about one-quarter of them were “zombies”, sucking up power without doing any useful work — perhaps because someone simply forgot to turn them off. “These are servers sitting around doing nothing except using electricity, and that’s outrageous,” says Koomey.”