In March 2023, Exmouth Lesuire Centre in Devon became the first UK site to benefit from free heat distributed through Deep Green’s heat-recapture cloud technology to heat its public swimming pool.
The technology is expected to reduce the pool’s gas requirements by 62%, resulting in savings of over £20,000 a year and will, according to Peter Gilpin, CEO of LED Community Leisure, “transform leisure centres up and down the country for the better.”
Deep Green is a tech start-up that uses its cloud data centre to perform ‘immersion cooling’ to capture heat expelled from operating data servers. This re-captured heat is then transferred into a site’s hot water system free of charge.
Current± spoke to Mark Bjornsgaard, CEO at Deep Green, to discuss what the future holds for the company’s heat re-capture technology.
Could you talk through how the technology works?
The beauty of it all is that it’s all fungible and all with a technology – that idea of technology – that’s been around for ages, but it’s just being applied in a different situation.
Immersion cooling is well understood, but data centres themselves have challenges using immersion cooling. This is because you densify (put loads more computers in the oil) leading to an even greater heat rejection problem which means that lots of data centres don’t want immersion cooling in their premises.
The theory of the technology is really simple, it’s computers in an inert oil and as the computers warm up, they heat the oil up, and then we just flow the oil into a heat exchanger, which takes the heat out of the oil and puts it into wherever it’s required. For example, the existing swimming pool hot water system. So the beauty about it is that it’s so easy to use, and so easy to install.
Following the technology first being rolled out at a swimming pool, are there other use cases you are imagining in the near future?
Pools are perfect for a growing segment of the data centre industry market. The graphic cards [powering the computer work in the installation] in Exmouth Leisure Centre are what’s called “high performance compute”, they are used for AI, machine learning, rendering movies, and they make a lot of heat. So when they make a lot of heat, we can catch the heat at 55 degrees, that’s how hot the oil gets, and because the pool only needs water at 30 degrees, it is perfect.
But the challenge and what’s blocked the data centre industry up until now in using normal cloud computing, which is more CPU based, is that you need to connect them to heat pumps. But of course, we’re no less welcome at the 11,000 district heating systems in the country, because if you’ve got a heat pump, and it’s the middle of winter, if we’re priming that to 30 degrees, that’s still amazing compared to minus five outside. So in order to use waste heat that’s ‘low grade’ we just need a heat pump.
Are there many challenges for rolling out the technology more widely that will impact Deep Green’s next moves?
I think of it the other way round, that actually computers are brilliant sources of heat, they convert 97% of their electricity into heat. As we can’t necessarily build enough heat pumps fast enough, we actually need computers as heaters to solve the problem, even if that’s just in the short term. So we’ve got a very aggressive expansion plan. But there’s so much to retrofit.
How much of an impact could collaboration make for Deep Green?
Absolutely critical. We can’t do this on our own. We can dream that hopefully in five years’ time, we’ve got enough credibility and momentum that the technology will be carried on in Deep Green’s name, but I suspect it will be powered by Deep Green, and then hopefully, the larger players will start to take it seriously.
We are having some really interesting discussions already, in a way that I didn’t think we would for at least a couple of years.
Do you think consumer buying habits increasingly towards sustainability will be enough of a driving force for companies to go green?
I think what we can do is signpost really clearly and get our message across to consumers.
The other thing to say is that as the data centre industry virtualises (where infrastructure as a service comes in) it’s becoming like a liberalisation of the computer market, similar to what was happening in the energy market 20/30 years ago. That liberalisation will itself mean that when you’re running, when you’re deciding where to put your datacentre, you won’t care where it’s running, but you will care if it’s carbon scope three negative.
50% of the data centre industry has no net zero plan and 97% are struggling to implement it. So 3% have got a plan. I suspect that’s probably the same the world over, but I think it’s fair to say the industry is certainly taking this much more seriously than it used to.
How do you think Deep Green’s technology is going to fit into the wider heat decarbonisation of Britain?
If you took all of Europe’s data centres, you still only heat 5% of the homes. So, the future is completely decentralised compute, the vast majority with heat recapture. That will almost certainly occupy us and many other people until 2035.
Hopefully, we can get there quicker and I think that’s another reason for sort of anchoring people on missions. We’ve got the infrastructure funding we just need everyone to say yes. It’s important to break it up and maintain our focus that we can get there. I think that’s often more easily understood and easier to achieve.