Data centers use a lot of energy, but they don’t just do it. The systems meet the needs of people and companies and do so more and more efficiently. Anyone who has implemented green design in their data center in recent years will have an advantage in the future.

“It’s actually a shame that you need so many applications and connections,” says Lex Coors. He is Chief Data Center Specialist and Engineering Officer at colocation specialist Digital Realty. “It is a big misconception that data centers consume energy. We all do this together. The entire economy around us is digital.”

Data centers are the engine of the digital economy, just as the steam engine was the driving force of the industrial revolution. Because we all place such high demands on servers and connections, the environmental impact of data centers is increasing worldwide. This doesn’t have to be a disaster. We previously described how large data centers are becoming increasingly efficient, so the impact of increasing digitalization on power and water consumption does not scale linearly.

More than a cool topic

Digital Realty has been working on this for quite some time. “Sustainability used to be a great topic to brighten up a company,” says Coors. “Now it’s getting concrete. Europe is working on rules. You have to know what’s coming so you can take it into account.” Coors himself sits on the political committee of the EUDCA (European Data Center Association) and keeps its finger on the pulse of the European Commission and the national industry associations of data center specialists.

“Europe is ready to talk to the sector,” notes Coors. “That’s a big difference to the USA, where rules apply. The EU relies on expertise. If they explain their goals and issues and we explain the implications of their proposed rules, we can all come to a solution. The legislation also applies to the entire industry, the competitive conditions are the same.” Due to the ecology discussion with competitors and the EU, the data center industry has known for a long time what to expect. Digital Realty has therefore set itself the goal of building new locations not according to the applicable rules, but rather taking tomorrow’s goals into account.

Pioneer sector

Coors complements the entire industry. The EU has a long-term greening strategy with the aim of being climate neutral by 2050. “The data center industry can achieve this by 2030. Our biggest competitors are our biggest partners in the area of ​​sustainability. We work together efficiently and results-oriented for greening.”

Our biggest competitors are our biggest partners in the area of ​​sustainability.

Lex Coors, Chief Data Center Specialist and Engineering Officer Digital Realty

According to Coors, one of the most important aspects of a green data center is looking forward. “True sustainability and green energy became a major issue around 2009,” recalls Coors. “At first it was a bit of a joke because the customer wasn’t interested at all. I then discussed this with the CEO. On the one hand, they wanted to gain a reputational advantage, but on the other hand, it gradually became clear that the earth’s resources were finite. That fell on deaf ears.”

Sustainable building

Digital Realty has not built its data centers as cheaply as possible, but rather has set its sights on 2030 over the past decade. The current buildings therefore comply with the guidelines.

“In 2002, we wanted to make significant cost savings,” Coors adds. “That’s why we removed everything that wasn’t necessary. This way we saved tens of thousands of euros per week. This led to a realization: Why should we even operate systems that are not necessary? Since then, we have always installed what was needed plus thirty percent for rapid scaling. The architecture of the data centers ensures that we can quickly add capacity without impacting the operational side.”

Truly green energy

Digital Realty itself has been powered entirely by green energy for more than six years. Coors is quick to point out that the company is committed to truly green energy and is not afraid of carbon credits or other things that add the green color to the energy after the fact.

“The electricity comes either from PPAs (Power purchase agreements), in which we have acquired a share in a solar or wind system, either from a GO (Guarantee of origin).” In the latter case, Digital Realty ensures that green capacity is reserved so that no one else can reserve electricity in the same green energy facility. Both designs ensure that the electricity used effectively is of green origin.

Water consumption

Data centers typically use a lot of water, but this is not the case with Digital Realty. “Our data centers no longer use additional water,” says Coors proudly. “We fill it up once and that’s it. This gives us a design that really prepares us for 2030.”

Use, don’t abuse is Coors’ mantra. “You can pump water out of the river, cool it down and then pump the warm water back into the river. Over the next five or ten years, the impact of such abuse is marginal. But if you install a lot of electricity at a river mouth over a period of years, you create a microclimate and ruin everything. There are lakes in the US that smell so bad because of the heat.”

residual heat

The residual heat that a data center generates is a complex issue, according to Coors. “We have been incorporating a heat exchanger into our designs since 2010,” he says. “The residual heat is available to the community free of charge for future projects. The problem is that the heat of the cooling water is too low. The temperature is around 31 degrees, although 60 to 70 degrees Celsius would actually be necessary.”

Chip specialists can play an important role in this. The CPU and GPU manufacturers of the world have cool specifications for their chips. “For air cooling, the water must be 21 degrees at the inlet and 30 degrees at the outlet. For the water cooling, the input is currently set to sixteen degrees. That’s a shame, because for every two degrees more you can cool for a month longer without the need for compressors.” Therefore, water cooling is currently not the ideal solution from a sustainability perspective.

Currently, water cooling is not the ideal solution from a sustainability perspective.

Lex Coors, Chief Data Center Specialist and Engineering Officer Digital Realty

Digital Realty, like other data center specialists, has to come to terms with the offer, which Coors regrets. “Turn it around, use 40-degree water for cooling, with an output of 60 or 70 degrees, and you kill two birds with one stone.” Less cooling gases are needed and the residual heat can be better used for a heating network. “Currently, chip manufacturers are not looking to adjust the thermal tolerances of their chips because these are closely linked to the performance of their chips. In other words, when it comes to residual heat, there is only so much a data center can do on its own.

What about diesel?

There are other things that Coors is looking at very prudently. For example, we see hyperscalers experimenting with alternatives to diesel to power emergency generators. “This is all about perception,” he says. “Such generators run perhaps ten hours a year. In the EU, the probability of the power grid failing is very low due to the architecture. If something goes wrong, it’s usually fixed within two to three hours.”

The switch to hydrogen doesn’t make Coors happy. “We want to produce 20 million tons of green hydrogen in Europe by 2030, and major industry knows what to do with it. It will be many years before it is our turn and green hydrogen is actually available. If we switch to hydrogen and green hydrogen is not available, we pollute with brown hydrogen. Then a diesel generator with HVO100 (renewable diesel), which already saves 97 percent of CO2 emissions, is the better option.”

And what about on-premises?

So there is still room for improvement. In particular, chips that run hotter could make the data center even more efficient. In practice, it is not difficult for Digital Realty to get the PUE below 1.2. PUE stands for Effectiveness of power consumption usageor how much additional power a data center needs to use for cooling, for example, in addition to the power the infrastructure uses for basic operations.

Efficient operation of IT infrastructure has become a professional job. Europe will also judge organizations on the sustainability of their IT. Hyperscalers have the necessary scalability for green technologies and colocation specialists certainly do too, as Coors shows. The case for on-premise data centers within companies themselves is becoming increasingly difficult to maintain. Lowering PUE accordingly, incorporating efficiency into data center design, using water and heat properly… all require a vision for the future and expertise. The data center sector may be a liability in absolute terms, but it is one of the more efficient sectors out there.

A little perspective is also in order. Coors has already pointed out that data centers consume energy not as a matter of principle, but to meet our digital needs. This digitalization brings advantages. Coors: “In any case, the energy consumption of a video call is much less than that of driving a car to a physical appointment.”