A report from heraldscotland says that a new £5.2m Scottish Government data centre, completed last year, will have a power usage effectiveness (PUE) rating of 2.7, which means it’s running at just 37% efficiency.
PUE is the ratio of total electricity usage in the data centre to the electricity used to run the IT systems. The more efficient the data centre the lower the PUE. New facilities should be aiming for at least a PUE of 1.5 or less, while the best-of-breed for a new build is a PUE of around 1.1.
According to the article, it means that the data centre will cost the taxpayer up to £7.14m in extra energy costs over five years, generating an extra 38,000 tonnes of CO2 emissions, compared to a more up-to-date designs.
Derek Schwartz, director of the Green Data Centre Alliance (GDCA) said a 2.7 PUE rating for a new data centre was ‘outrageous’, but a Scottish Government spokesman said the data centre was ‘world-class’, and that "As measures to optimise energy efficiency are fully implemented, we expect the PUE to improve to a figure closer to 1.4."
Review: Where do you start with this one?
It’s certainly true that a PUE of 2.7 for a new data centre is outrageous. Under ‘extenuating circumstances’ you could point out that it’s currently only 54% occupied and in fact not a new facility but an existing building that’s been refurbished.
But hasn’t the concept of modular data centres reached Scotland yet? The new data centre is not expected to reach full capacity until 2015, which means, using heraldscotland’s figures, it will be wasting upwards of £3m before it reaches its 'optimum efficiency, a not particularly impressive PUE of 1.4.
Why not invest in a flexible, modular data centre to fit the current IT requirements now and with a PUE as low as 1.05, saving even more cash and emissions? It can be extended as and when required. The £3m+ savings could be used to buy the land to put it on, if they don’t have the space already.
There are a couple of other things not mentioned in the article. Scotland doesn’t have a particularly warm climate so is an ideal location for ‘free air’ cooling, i.e. using external air to cool the data centre, rather than chillers and other energy-hungry cooling equipment. It is also where much of the UK’s wind generation takes place. Using renewable energy doesn’t increase efficiency and is not free, but it does reduce carbon emissions. Is the new data centre benefiting from these location-based advantages?
Whichever way you look at it, the Scottish Government seems to have missed a golden opportunity to save taxpayers money and build its environmentally credibility.