At the height of the mania surrounding cryptocurrencies, such as Bitcoin, a common statistic was that processing these digital currencies required more energy than Denmark used on its own. Globally, it’s believed that data centers account for around 2% of all electricity output.
At a time when so many are urging society to make any post-COVID recovery as green as possible, there is an obvious desire for the data centers that power so much of the modern world to be as green as possible. The scale of the challenge is considerable, with data from Technavio highlighting that the data center industry is predicted to grow by around $284 billion per year as the industry aims to support the 2,343 trillion megabytes we’re projected to be consuming per year.
The sector has made considerable strides in recent years to become more energy efficient. This is highlighted by the fact that despite the volume of work done by data centers rising by 500% between 2010 and 2018, energy consumption only grew by 6%. This has been due to a concerted effort from the industry to upgrade hardware, while the likes of Deepmind have been deploying their considerable intellect to make data centers more efficient.
Jevons paradox
There remains a sense, however, that data centers are a classic case of the Jevons Paradox, which states that as activities become more energy-efficient, we generally start consuming more of that thing, hence energy usage stats much the same rather than falling. This certainly appears to be the case with the statistics mentioned above. Nonetheless, with the computing demands of the world continuing to grow, the industry is having to deploy increasingly creative means to ensure energy usage doesn’t mushroom.
For instance, Microsoft has been building a server farm on the sea bed off of the Orkney Islands in Scotland. The servers were initially installed in 2018 and were connected to land by cable. The company recently revealed that the facility was generally a lot cheaper than land-based facilities, due in large part to the lack of human access to the facility, which resulted in lower maintenance costs.
They also highlighted how locating data centers underwater could help to place them close to major population centers while avoiding the very high land costs associated with building a data center in the city. For instance, installing a data center on the sea bed near to London or New York would be considerably cheaper than doing so on land, while the immersion in seawater also helps to keep the facilities cool.
Re-using heat
The Stockholm Data Parks illustrates another approach as they try to re-use the heat generated by their data centers to provide fossil-free heating for the local community. The project, which has been set up by the City of Stockholm in partnership with energy provider Exergi, grid operatorEllevio, and network provider Stockab, offers a range of greenfield sites across the city for data centers to be built.
Each facility utilizes pumps to capture and then repurpose heat, and the group believes that up to 10% of Stockholm’s entire heating demand could be provided by the project. A number of contracts have already been signed to develop data centers in the SDP Kista region of Stockholm, with a collective 20 megawatts of heat projected to be reclaimed. The facilities, which are scheduled to start delivering heat early next year, will allow data centers not only to boost their sustainability credentials but also to generate money from the heat that would otherwise go to waste.
This kind of project is of huge importance to Amsterdam, which is believed to host around 30% of all data centers in Europe. This concentration of computing power makes it difficult for the city to meet its ambitious sustainability agenda, but the industry is confident that the ability to reclaim the residual heat generated can satisfy all parties. It’s an effort that has already seen 10,000 public housing units replace their traditional heating systems with district heating systems.
Such an approach isn’t easy to replicate, however, with incumbent energy providers sometimes reluctant to disrupt their own business model to allow such energy to be reclaimed. As in so many industries, dominant incumbents can often elicit their political clout to maintain the status quo. Stockholm was also able to proceed as quickly as it was because the city had extensive district heating systems that the data centers fed their heat into. Such an approach is far less straightforward in a city such as London, where the underground infrastructure means that a more complex process would have to be initiated.
Nonetheless, these early examples help to illustrate what can be achieved, and with the desire for a green recovery from COVID-19 considerable, there is every motivation for the industry to try a range of creative solutions to ensure that it can continue satisfying our thirst for data while also doing so in a sustainable way. The economic aspects of heat recovery systems are far healthier when such approaches are built into data centers from the beginning, for instance, so hopefully, the next generation of data facilities will be sustainable from the start.
