Mike Hayes, Applications Specialist, FlaktGroup, discusses the evolution of cooling technology in the data centre space and provides insight into how the organisation offers cooling solutions to its customers to allow them to meet their business and sustainability goals.
Can you introduce yourself to our readers?
I’m Mike Hayes, an application specialist at FlaktGroup, looking after the DENCO data centre range of products.
Can you tell us about some of the trends you’re seeing so far in the cooling space and how these impact you as a company?
People can’t seem to build data centres quickly enough, which is great news for us. We’re seeing larger and larger data centres, we’re seeing higher and higher water temperatures. We can’t really call it chilled water anymore. We’re talking about temperatures of up to 25 degrees, no longer the old building services temperatures of seven degrees Celsius or even 10 degrees Celsius that came later. This of course is making things much more efficient. We’re talking about year-round free cooling, we’re talking about sometimes losing the refrigeration totally from the system. If you can cope with air going onto your servers at 28 degrees for a few hours in summer, then you don’t actually need any chillers or mechanical refrigeration. To put some numbers to it, we’ve installed over 180 MW of cooling in 2021. And that gives you some idea of the range of products we have and what they’re doing.
What sorts of conversations are you having with existing and potential new customers about cooling?
We’ve introduced DENCO as a brand name again – ‘DENCO by FlaktGroup’. FlaktGroup is a very large company of which DENCO is but one product. ‘Flakt’, by the way, is the Swedish word for ‘fan’, so we’re the fan group really, and within that we have DENCO products. We started to use that brand name again and I think it’s really paying dividends. We’re having customers come to us and tell us they’re using some of our equipment and that it’s 15-20 years old. They then ask if we could perhaps refurbish or replace it. And that’s been missing for the past few years as people haven’t associated FlaktGroup with DENCO, but of course we’ve been in the data centre cooling industry for 50+ years.
What sorts of challenges are customers experiencing when it comes to cooling technology and how do your products help customers to tackle these?
The big thing is energy efficiency for sure. Even at current power right usage rates a kW is worth £1,000 per year approximately, so if you can save 100 kW on your load that’s £100,000 per year. So the cost of energy is certainly going to help us to benefit our customers. As the costs go up the payback periods for some of the energy efficient systems come way down. We’re already looking at two years being a typical payback period for investing, for example, in the free cooling system rather than just a straight chill water system. And we see this trend continuing – data centres are getting more high density and we have to cope with that in terms of cooling by air. We’re looking at hooking into water cooling systems as well and we have all the products to do that. We have fan walls, air handling units of all sorts of types, adiabatic cooling, run-around coils, free cooling systems, typically glycol-based free cooling systems. You name it, it’s all there under one roof so we can apply whatever the best solution is for the project.
How do you expect the market to evolve over the next 12 months and how will you innovate alongside this?
We expect the market to demand higher cooling capacities. In days gone by, a 100 kW cooling unit was a big unit. These days we’re looking at two and 300 kW and one particular end-user is asking us to build 500 kW cooling units. So it seems to be that bigger is better. That sort of thing wouldn’t have been dreamt of perhaps 10 years ago and certainly not when I started in the business in 1979. People said ‘Data centre cooling? You don’t want to get involved with that because computers are getting smaller and smaller and using less and less power so it’s going to be a bit of a dead-end business’. How wrong they were.
How do you ensure your operations are sustainable in the race to net zero carbon?
By minimising the energy usage is a simple answer to that. The DX systems for example, have pretty bad press. Yes, they used to use 50% of the server power, so the partial PUE would be 1.5. But these days with our inverter compressors, we can get that down to 1.2 even for a basic direct expansion system. And if we put our free cooling system on it, then that annualised PUE comes down to 1.1. So, for example, for every 100 kW of cooling you’re doing, you might – with your existing chilled water based or DX systems – be paying £50,000 per year for that 100 kW of cooling in terms of energy. With our new systems, we can cut that down to £10,000 per year. So straightaway, for every 100 kW, there’s potentially a £40,000 saving. It doesn’t take much for you to see how the payback periods come right down particularly if energy costs go up, which they’re going to.
What advice would you offer to those looking to invest in cooling solutions?
I would say invest in energy efficient systems – don’t just look at the CapEx because these sorts of cooling units can use up their CapEx within their first year of operation. A typical 50 kW unit, despite whatever you paid for that unit, you might be paying the same amount of money to run it for one year. So we must get away from this focus on the CapEx and start looking at the OpEx on these systems.
Do you have any key messages you’d like to share with our readers?
Yes – it’s all about energy efficiency. I think I’ve emphasised the point enough but with the recent increases in power costs, it really is big money in terms of looking at the energy efficiency and free cooling and such like. We have to look very carefully at running costs of our systems.
