Mats Carselid, of Alfa Laval‘s data centre cooling team, suggests why it’s critical that the data centre industry progresses beyond convention towards more financially viable alternatives…

Data centres underpin the growing modern economy. The United Nations predicts that by 2018, the world’s population will reach 7.8 billion and according to Cisco, half of them will have residential internet.

Data centres are under a lot of pressure. Not only must they meet soaring demand, but also secure safe system performance, assure compliance with current environmental guidelines and future-proof against upcoming regulations resulting from COP21; all while curbing growing expenses and remaining competitive. It seems almost impossible. However, there may be a hidden resource waiting to be capitalised that makes this challenge easier.

It is estimated that data centres consume between 1.5 – 3% of the world’s electricity. This is a substantial portion of the total output, yet forecasts claim that by 2020 this share will reach 7%, making data centres the fastest growing user segment for electricity. Electricity will become an increasingly significant area of operational expenditure for data centres, increasing consumption combined with price rises will have a substantial impact on bottom lines. Legislative pressure on energy consumption and share of emissions is also increasing. It is time to progress beyond conventions towards proven, financially viable alternatives.

Heat harvesting

Selling hot water to a city’s energy supply can raise the effectiveness of a data centre and lower the PUE

Harvesting the heat usually released into the atmosphere is an effective, but seldom-used way for data centres to harness higher room temperatures, increase energy-efficiency and ultimately reduce operational expenses. Viewing the data centre as a producer of heat may initially seem hard to believe, but we have already seen several examples in the UK, Sweden and across Europe in which data centre waste heat has been harvested and directed to heat everything from swimming pools and neighbourhoods to entire cities. Harvesting not only makes good sense from an environmental perspective, but also possibly from a business standpoint as heat can be sold to commercial networks at spot price.

Enjoy a second income

Harvesting and selling waste heat for profit is already employed in neighbouring industries. It makes sense from a sustainability standpoint and from a business perspective as well. Added to this, the addition of regulatory incentives for going green make an even more compelling case for viewing waste heat differently.

Selling hot water to a city’s energy supply can raise the effectiveness of a data centre and lower the PUE, as it will act as a second income in addition to the data services the facility provides. Harvesting heat from a data centre requires a piping network of supply and return pipes connected to the heat pump, a positive mindset towards district and local hydronic heating and the will to use the environmentally-friendly technology of large- scale hot water production, rather than small individual boiler units.

Such a shift is, of course, associated with investment, but regulatory incentives combined with new technologies that maximise heat recovery, shortens payback time and increases rate of profit, meaning that conventional CRAC cooling can become a thing of the past.


This post originated at Data Centre Management magazine, from the same publisher as The Stack. Click here to find out more about the UK’s most important industry publication for the data centre space.