PUE and other efficiency measures are useful, but data centre owners are chasing money now, says Peter Judge
Efficient data centres have always made an effort to meet commercial needs – but I think the economic side of the movement may soon eclipse the “green” side.
The move to the cloud is driving this, I think. “Cloud-based services [like Facebook and Google], have the ability to build efficient data centres in locations where there is cheap power, and to highly utilise the IT equipment,” said Mark Monroe, executive director of the The Green Grid. “Their primary function is to drive the cost of a transaction down as low as it can be.”
The Green Grid has just had its annual European conference, over two days in Paris and London, and is reacting to this world, where it is all about the lowest cost for transactions. “Amazon can deliver a CPU-hour, for 10 cents,” said Monroe. He would have delivered the same measure for $3.75, two years ago, when he worked on Sun’s sustainable data centres.
Monroe brought me up to date on the Grid’s work, along with one of the Grid’s leading lights, Harkeeret Singh, head of energy at Thomson Reuters, and I believe I detect a new focus on economics from this industry consortium of users and vendors.
It’s more about the money than the tech
The Green Grid has been known for the PUE measure of effiency, which has been picked up by various interantional bodies, and is regularly quoted for any new efficient data centre development.
At first sight, its other work looks like a continuation of that sort of effort, providing yet more ways for centres to measure their performance and compare themselves, including the still-under-development CUE and WUE measures of carbon-usage and water-usage respectively.
The Data Centre Maturity Model (DCMM) is the pinnacle of this sort of measurement, a complex definition of a data centre’s progress towards efficiency, which will shortly have its own user-friendly online tool for users to generate their own data centre’s score.
But alongside these measures, the group is coming up with a wide range of other material, which is increasingly designed to look hard-nosed, practical and, let’s face it, commercial.
Saving money, not PUE
The latest Green Grid White Paper surveyed members’ use of economisers, the cooling system which offers free air cooling and replaces the use of chillers. I first heard economisers trumpeted as a way to improve PUE. According to the survey, however, they do improve efficiency, but have no discernible effect on PUE.
“There was no statistically significant difference between the PUE reported by those who use economizers and by those who do not,” the report found.
They are taking off rapidly amongst Grid members, however, because they save money. Around half the members surveyed are using economisers, and they are using them for almost all the hours allowed by the local climates (which turns out to be around 4,000 hours). They are doing so, because they are saving money – around 20 percent of the energy bill, with a payback time of around 20 months, according to Monroe.
Other research to come will look at the carbon tax regimes of large parts of the world.
‘Taxes will go up’
“In the UK, you already pay four carbon taxes,” said Singh, listing out the UK’s CRC scheme, which has become a tax on energy users, along with three measures applied via energy providers – the Europe Emissions Trading Scheme, the Climate Change Levy, and the Renewables Obligation.
The problem with these schemes is that – unlike the laws of thermodynamics, on which efficient data centre technology relies – they are complex and changeable. “These taxes will go up, and carbon will become a bigger cost,” he said.
The Green Grid is planning a paper which adds up and compares the energy taxes and carbon taxes in thirteen different countries within Europe and the Middle East, he said.
That is a big step away from comparing the merits of one form of cooling with another. It takes the Grid into a political arena – although Singh is very quick to state that the comparison it produces is simply for information, and is not a lobbying tool.
However, a coherent roundup of national positions on carbon taxes will clearly be a very important input for companies deciding where to site their data centre – and will clearly be hotly analysed and contested by the governments and special interest groups in different countries.
The Grid says this is a logical exension of where it’s always been operating – I think it’s a definite shift, and I look forward to seeing it working out in practice.