In recent years, global economies transformed from being physical-powered to being digital-powered. Entering the next phase, transforming to becoming ‘data-powered’ – high-density data is fueling economic growth. With increased digitization, the physical economy has shifted to a digital economy, which is now entering a new form: the data economy.

At Digital Realty in Sweden, we take it one step further: the circular economy. Pioneering the industry, our Stockholm data center campus has been connected to the Open District Heating Network (Öppen fjärrvärme) since 2015, contributing to heating tens of thousands of nearby homes with excess heat from our server halls.

Increasing data demands from every corner of society, and AI breaking new ground, unprecedented exponential data growth is happening before our eyes and therefore so is workload demands.

Naturally, this places enormous demands on professionally managing the infrastructure of where data is stored and processed sustainably.

The IT industry, particularly the operation of data centers, has a vast inherent climate impact potential, and it has never been more urgent to consider our data-habits and their ecological impact. Stockholm Data Park is the initiative by the City of Stockholm, Stockholm Exergi, Ellevio and Stokab, incentivizes the data center industry to reuse excess heat, striving for a fossil fuel free city by 2040. The collaboration, and the participation of data centers like ours, is the catalyst in redefining green computing by enabling heat recovery through the infrastructure already integrated below the city of Stockholm.

Whether you’re viewing it from a business, research, or consumer perspective, you are undoubtably dependent on technology in one form or the other. Similarly to strategically monitoring utility bills at home, the power usage effectiveness, PUE, of data workloads is critical for optimal performance, price, and the environmental footprint.

So how do we power the demand and where do we go from there?

In short: The data center industry becomes a utility provider.

Ahead of the curve is the city of Stockholm with its’ cooling and heat networks already integrated in the city’s infrastructure, currently collaborating with more than 30+ data centers. Originally built in the 1950s to utilize excess heat from industrial factories, the Stockholm Open District Heating Network has evolved into a sustainable energy powerhouse. Digital Realty has been a cornerstone of this transformation. Our Stockholm data centers, unexpected yet perfect partners, have seamlessly integrated into the city's heating network heating tens of thousands of homes in Stockholm. Since 2015, heat exchangers have enabled us to return recycled residual heat from our data halls into the network.

The warmer the water we deliver to the network, the better the returned output. Boosting the ongoing efforts, a large proprietary investment in heat pumps in the STO6 data center, Digital Realty Stockholm further improves the yield of reusing excess heat. The pumps heat the residual hot water on site, so it is fit to be distributed directly into the network eliminating the need for subsequent temperature augmentation.

While the cold Nordic climate is ideal for operating data centers, it is accompanied by an inherent prerequisite of heating homes, offices, and government buildings. Recycling heat that would otherwise be wasted is not only imperative in fighting climate change, but also crucial for the Swedish population relying heavily on heating measures in their daily lives.

The Nordic region is already leading in low-cost low-emission energy, and at Digital Realty, we have been using 100 percent EDP matched renewable energy in our data centers in the Nordics since 2012. We design our data centers according to the latest industry standards, and we use free cooling. As participants of the EU Code of Conduct for Energy efficiency in data centers, we not only meet, but surpass, expectations. When it comes to design and sustainability in the data center itself, we are shaping the industry.

With high-density data workloads and AI-innovation on the rise, it is paramount for businesses to be able to safely deploy, scale and innovate their efforts within an eco-system built not only to sustain business growth demands but equally importantly sustaining environmental considerations too. Ultimately benefitting our customers, leveraging the Nordic climate, free cooling, closed cooling rings, and Open District Heating, we are not only contributing to heating tens of thousands nearby homes annually, we also consistently reduce our carbon footprint thereby reducing energy costs.

When you move your data workloads to a Digital Realty Stockholm data center, you benefit from a stable, secure, and scalable capacity to meet future data needs, as well as positively impacting your company's sustainability efforts.

We continue our innovative approach to reshape the city's energy landscape, heating one home at a time.

Waste Heat in Data Centers: A Valuable Contribution to Greater Energy Efficiency and Sustainability