Opinion: The growing importance of sustainability in data centres
Article by Aruba S.p.A infrastructure manager Alessandro Bruschini
Just as with personal computers, the data centres that contain the servers that power our emails and data sharing culture generate heat. The only difference is that data centres generate much more heat.
With this in mind, it’s no surprise that the primary source of energy consumption in most data centres is cooling. This is why it’s so important to find the right solution, as overheating can have negative consequences on performance and permanently damage hardware.
Temperature management is made even more complicated by the numerous existing approaches to maintaining the necessary levels, as well as by the cost attached to the implementation of many of these solutions.
Recent investments in the Nordic region made by some tech giants to benefit from the cold temperatures and the resulting cost savings provide a good reminder of how expensive data centre cooling can be, especially as the issue becomes more prominent.
The real cost of cooling
Up until recently, the cost of energy and data centre cooling wasn’t on the radar of decision-makers and wasn’t always considered in Total Cost of Ownership models. But it can no longer be ignored.
The ongoing data revolution and the increasing importance of where and how that data is stored have pushed the demand for servers up, along with their energy consumption.
A recent report suggests that by 2025, data centres will consume one-fifth of all the electricity in the world. This energy usage mainly comes from large industrial equipment such as pumps, chillers and cooling towers, which are used to regulate data centre temperature.
However, regardless of how effective these solutions can be, the fact that data centre operators will always need to invest significant amounts into maintaining and improving their efficiency makes them quite unsustainable.
The financial impact of data centre cooling solutions is increasingly coming into light as the demand for data centre capacity rises. As a result, investments that could be put into increasing capacity and improving performance are inadvertently going towards cooling the data centre.
Greener data centres through natural cooling
As businesses and individuals endeavour to be connected 24/7, rising energy consumption and costs won’t alter the data centre’s pivotal role in our modern economies.
But with the rising cost in mind, most data centre operators now realise that this situation needs to be addressed. The level of energy consumption cannot continue to rise indefinitely and many have started taking steps to make their facilities more energy-efficient.
For example, The Green Grid, a non-profit consortium working to improve data centre energy efficiency, recently published a survey suggesting that almost half of US-based data centres are now using natural cooling to save energy and costs, with another quarter considering doing so in the near future.
The use of natural cooling is becoming a growing trend for data centre operators who strive to reduce power costs and carbon emissions, considering that most modern servers are able to operate at a temperature of 27°C.
And this doesn’t mean they have to be in areas with extreme weather conditions. For instance, consulting company Capgemini recently opened a data centre in Swindon, (United Kingdom), which it says has delivered 80% savings in running costs and reduced carbon emissions by 50%.
The reality behind natural cooling
Contrary to what some may think, natural cooling requires more than just opening a few extra windows. It requires a complex process of filtering outside air to provide the desired level of air temperature to keep the data centre cool.
There are already many approaches to natural cooling available. The most common is the free-air cooling system, which draws in air mainly through filters that remove any particles or impurities. This system measures the moisture content and processes it in real time. Even if air is at the right temperature, elements such as impurities or the wrong level of humidity can cause serious problems in the data centre.
Another approach to natural cooling uses heat wheels. This system exchanges the heat generated by the data centre with cooler outside air through large metal surface areas and a superior thermal mass of metal that improves the overall heat exchange.
Both of these systems, like most of those associated with natural cooling, bring a considerable amount of external air into the data centre, which has to be constantly filtered to control the amount of moisture that is let in.
There are several other forms of natural air cooling, and each system has its advantages depending on the overall architecture of the data centre you are operating in.
Choosing a sustainable option for the data centres
The global cloud data centre traffic was 6 zettabytes (ZB) in 2016, and it is now projected to reach 19.5 ZB per year by 2021. As such, there can be no arguing the fact that the need for data centre capacity will continue to rise at a steep rate.
Facing this expected growth and the demands that will come with it, decision makers cannot afford to ignore sustainability when it comes to building and managing their data centres.
To carry on growing, the data centre industry will have to turn to green methods of energy consumption and production; starting with the main energy cost: cooling. In today’s data-driven world, it’s an issue that simply can’t be ignored.