You’ve probably heard countless data centres shout about their “sustainable” credentials. But, for many facilities, sustainability may be limited to little more than using renewable energy.

It’s time to wake up: 2030 is just four years away, and energy reduction targets are fast approaching. With high-performance compute (HPC) demand exploding, UK data centres have a responsibility to do all they can to minimise environmental impact.

So what do truly sustainable data centres look like? Donating heat from servers via district heating systems is a powerful way for data centres to holistically reduce emissions while giving back to local communities. What’s more, choosing a colocation solution with a heat donation programme offers many benefits for your enterprise. Read on to discover those benefits and find out exactly how heat partnerships come to life.

How does heat reuse work in UK data centres?

Imagine you’ve got twenty tabs open, you’re downloading a hefty file, all while tapping out a quick reply to that urgent email — oh, and you’re in a video call. You can hear your laptop fan working overtime, and you can even warm your hands on the battery.

Servers in data centres get just as hot as your overworked laptop, but on a massive scale. Running HPC releases a lot of heat, which many UK data centres let go to waste. But up to 95% of this heat could be captured and distributed to local facilities via district heating systems. What’s more, these networks then return cooler temperatures to data centres, reducing their cooling costs. You might have heard of data centres heating residential buildings or swimming pools. But beyond the usual candidates for heat reuse, other projects are pushing the boundaries of what’s possible across food, wellbeing, pharma, and energy.

Donating heat can do even more than reduce emissions and improve efficiency. Collaborating with district heating systems is an opportunity for data centres to build new urban ecologies. Planning permission, local council pushback, and citizen protests are all barriers to data centre builds. But, by providing benefits for citizens through heat donation programmes, data centres can become part of local ecosystems rather than draining their resources. Working with communities means data centres can overcome the usual pushback, offering fast deployment for enterprises.

Deep Green’s blueprint for green urban ecologies

So, how does Deep Green do this? To ensure the heat we donate provides maximum value, we have two strategies for locating our data centres. Firstly, we build data centres in existing industrial or urban ecologies, where there’s a need for heat from district heating systems or local partners. For example, putting a data centre underneath a leisure centre means heat from servers can warm the swimming pool. The other option is to establish and nurture new ecologies by building data centres and inviting projects in need of heat to build alongside us. These ecologies become hubs for cutting-edge pioneers of heat reuse to collaborate with Deep Green data centres and use our heat for their operations.

Examples of these innovations include prawn farms, where heat from data centres can warm water to the optimum temperature for prawn growth. This offers massive benefits for these aquaculture systems, allowing them to use 20 times less heat, 10 times less water, and 12 times less electricity than competitors. Another example is microalgae production. Data centre heat can offer the warmth needed to cultivate microalgae, producing ingredients such as natural omega-3, antioxidants, and nutrients for food and nutrition companies.

Why heat donation matters when choosing a colocation partner

CSOs and CTOs alike, listen up. A UK data centre with a heat reuse programme offers benefits for your sustainability performance and your bottom line.

Donating heat means the district heating system reduces its emissions. When you purchase HPC from a colocation solution that donates heat, this emission reduction counts as avoided emissions for your enterprise’s scope 4 reporting. Heat reuse also provides you with a valuable ESG narrative, demonstrating environmental benefits, social good, and community collaboration.

Another benefit of heat donation is that it reduces a facility’s cooling requirements, because district heating systems return cooled water to data centres. Less energy used on cooling means a lower data centre PUE and cheaper colocation costs, resulting in savings for your enterprise.

The impact of heat reuse on data centre efficiency metrics

When you’re choosing the perfect colocation data centre, you’ll likely take a good look at its metrics. Data centres that donate heat improve across the following metrics, demonstrating true sustainability both within their facility and in the wider community.

• Data centre PUE, as heat donation means less cooling requirements and a more efficient facility

• Energy Reuse Factor (ERF), which illustrates how much energy is put to use a second time

• Net PUE ((Total facility power – Heat reuse) ÷ Compute power), which gives a picture of efficiency beyond the data centre itself

• Water Usage Efficiency (WUE), as less water is used for cooling

Data centre heat could fuel the next generation of urban ecologies

Within a generation, data centres could heat our homes and public spaces for free, while also fulfilling 30% of our industry’s heating requirements. Establishing urban ecologies — or connecting with existing ones — means data centres can collaborate with communities and offer positive benefits for local people.

Want to find out more about our latest heat reuse project?