Klimaneutrales Rechenzentrum

According to a Bitkom survey one in two German enterprises wants to be climate-neutral – and the EU Commission wants data centers to be climate-neutral by 2030. The European Green Deal has been called a “man on the moon moment” for Europe. But targets on paper will only change the world (or have a positive impact on the environment) if they are actually implemented, whether they relate to energy efficiency, green power or hardware. So what are the problems, how do we solve them and what should we be doing? One thing is clear: We can’t create a new, green future unless we do it resolutely, and together.

Modern data centers are an important part of the “machinery” driving the sustainable digital transformation. As the pace of digitalization picks up, we are seeing an increasing number of initiatives setting the coordinates for a greener future – from the German government’s Digital Agenda to the EU’s most recent “Fit for 55” climate package. Launched in July, “Fit for 55” envisages a 55% net emissions reduction target for 2030 based on the 1990 levels. An ambitious target was already set for data centers back in 2020 when a European Commission paper stated the EU’s goal of 100% carbon neutrality for the entire ICT sector by 2030 – with its own resources, not with emissions certificates. The objective is clear, yet the means of achieving it are less so: “…more energy efficient, reuse waste energy, and use more renewable energy sources”. Data center operators, colocation services providers and data center tenants now face a crucial climate challenge: How to get to climate neutrality from the current status quo?

More energy efficiency – a question of perspective

Vast improvements have already been achieved in the area of data center energy efficiency. Power consumption per gigabit of data is today 12 times lower than in 2010, and electricity-related carbon emissions at data centers in Europe have been declining since 2015. Power Usage Effectiveness (PUE) is used as a measure of energy efficiency. It represents the ratio of total amount of energy used by a data center facility to the energy delivered to the IT infrastructure. The average PUE for data centers in Germany (not including stand-alone servers) declined between 2010 and 2020 from 1.98 to 1.63. In comparison: The maincubes FRA01 and FRA02 facilities in Frankfurt am Main already have a very positive PUE of under 1.3. But is this still the most informative parameter – and how can it be optimized? Here’s an example. At night only 100 of the 1,000 servers hosted at the data facility are operating at full capacity. The others are in “idle mode” because the data center tenants aren’t using them. If the 900 unused servers are switched off, energy consumption falls, which is good, but the PUE value that is so often used as a sustainability metric is then higher as a result. Which of the two is more relevant, PUE value or energy consumption? This has been a  matter of debate for some time now. maincubes’ strategy is to ensure the optimum use of all resources, operate data centers at capacity, and distribute costs. All sides benefit, especially colocation tenants, if data center operators verifiably and transparently communicate their racks’ power consumption, because this simplifies the decision on which colocation partner to choose, and improves planning reliability. On the basis of these and other factors, it is possible to develop joint solutions that optimize the operating time and power consumption of servers and other equipment.

Higher efficiency and greater compute density can also be achieved with OCP applications. The maincubes data center in Amsterdam (AMS01) is the only facility in continental Europe that is already certified as OCP Ready™. One of the main advantages of OCP-based hardware is that any company can download existing design files and use them to start building  individual solutions that dispense with unnecessary components, thereby saving resources and energy. This approach enabled Facebook to design a data center in Oregon that was 38% more energy efficient to build and 24% less expensive to run than the company’s previous facilities. As a rule, new hardware is a drain on resources. Equipment such as servers and components can be reused, repaired or recycled and refurbished hardware is another way for data centers to net a green win. If everyone gets on board the data center industry can make a big difference.

Data centers and circular energy systems

As an increasing number of economic sectors embrace digitalization, the mission is to make everything greener. The German Ministry for Economic Affairs hit the nail on the head when it said, “Digitalization is a double-edged sword for the environment and climate.” The aim is to ensure that the digital transformation is as eco-friendly as possible, and that it delivers benefits for the environment, climate and nature. One important and often hotly debated issue in connection with data centers is waste heat. Should we believe what we read about how the heat recovered from data centers could be used to heat entire cities? And how sustainable would that really be? The waste heat from data centers is not hot enough for use in district heat networks, so heat pumps have to be deployed to raise the temperature – and that involves significant costs and resources. Waste heat recovery does not primarily serve to improve the facility’s own energy efficiency, but to promote decarbonization in the heating sector. A far more effective option would be to feed the waste heat into low-temperature heating networks, or to distribute it directly to consumers (e.g. greenhouses). Opportunities to feed captured heat from data centres into systems will only benefit everyone involved if they are practical, environmentally sound and cost effective. Although data center heat recovery is already a reality in some parts of Northern Europe Germany still lacks the necessary infrastructure. Frankfurt-based utility company Mainova uses waste heat from a major colocation data center to cover around 60 percent of the heat requirements of 1,300 new apartments, but the concept hasn’t reached the necessary level of market maturity yet, so this is still a pilot project.

There is also the issue of how waste heat affects the climate and temperature in cities. We do not yet have any reliable data on this. So instead of  simply continuing to use waste heat, we should focus on avoiding and minimizing it by using efficient cooling technologies. Another issue with waste heat recovery is that heat is generally only required in winter. At that time of the year, though, data centers can be efficiently cooled with modern free cooling concepts that generate minimal waste heat. It therefore makes sense to select locations in cooler climates for new data centers, particularly when you consider that data centers are generally operated for 20 to 30 years at one location. Proximity to urban areas offers additional key advantages, such as connection to a high-reliability power supply and a well-developed fiber optic network. These are the reasons why the highest density of data centers in Germany can be found close to the world’s largest internet exchange, DE-CIX in Frankfurt.

Stay cool – but how?

Cooling uses up a lot of energy, which is why it is one of the main starting points for reducing carbon emissions. Unless alternative refrigerants are used, it will be almost impossible to meet climate targets – which poses challenges to both the data center operators and the refrigerant manufacturers. Partly fluorinated hydrocarbons (HFCs) with high global warming potential are still used for cooling applications. EU Regulation (No. 517/2014) envisages an HFC phase-down by 2030. The German Environmental Agency introduced “Blue Angel Certification for Colocation Data Centers“ to promote the use of halogen-free refrigerants (such as ammoniac or propane). However, data centers are still reliant on refrigerants containing halogen for certain cooling applications, so we urgently need other more eco-friendly alternatives with the necessary high level of effectiveness.

Racks, on the other hand, can be "naturally cooled” and Microsoft actually has data centers submerged under the ocean. That’s one option, but it isn’t possible everywhere, and it consumes water resources. Other operators use immersion cooling – the practice of submerging computer components or full servers in a thermally, but not electrically, conductive liquid (dielectric coolant) – or climate-friendly natural ventilation, which is what maincubes uses. At the FRA01 facility the installed “KyotoCooling” system helps it to achieve annual building acclimatization efficiency of up to 90 percent. FRA02 also has a cooling wall system that has chilled water flowing through heat exchangers for additional modular cooling as required – which comes with the additional benefit of greater energy efficiency.

Green electricity – but where to source it?

The sector also has to assume responsibility for more sustainable power sourcing – even though this is a challenging objective to achieve. Here’s an example. European data center energy requirements increased by 55 percent between 2010 and 2020. According to a Borderstep study in 2020, the some 50,000 data centers in Germany consume the same amount of energy as Berlin, and the data centers in Frankfurt am Main already use more electricity than Frankfurt Airport. One goal is to obtain more power from renewable energy sources and there are already pilot projects underway. windCORES is building data centers in wind turbines, and Windcloud opened a data center plus algae farm powered by wind energy, solar and biogas electricity in 2020. These projects are an excellent step in the right direction. However, they cannot yet compete in terms of capacity with the Frankfurt data centers. The number of wind energy licenses issued in Germany declined in 2020, by the way, to a level 40 percent below 2015. This is an area  – where additional political tailwind is called for.

At first glance, one of the forecasts in the above-mentioned Borderstep study appears to make a positive prediction: a 30% reduction in greenhouse gas emissions in Europe by 2030. However, it doesn’t apply to Germany, where slower progress is being made in green electricity generation because, as legislation currently stands, the fossil fuel phase-out could continue until 2038. In 2019 coal still accounted for around 33 percent of the electricity generation mix in Germany. A faster phase-out could therefore also speed up the rate of carbon emission reductions at data centers. The EU’s new “Fit for 55” climate plan could provide a push in the right direction because it proposes to phase out free emissions allowances and reduce the total number of CBAM certificates issued. The price of the certificates will make coal-fired power stations less profitable, which could give renewable energies a boost.

No more position papers!

Is it an ambitious plan? Yes. Is it impossible? No. However, it’s time people took action to implement it instead of writing position papers. Policymakers, industry associations and manufacturers have an obligation to work together on developing and implementing realistic solutions. Collaboration is key and competitive thinking will hinder rather than help the fossil fuel phase-out. maincubes embraces a win-win approach by making its own data centers as climate neutral as possible and collaborating with other market players on the achievement of climate targets. For example, maincubes is a member of VIRZ e.V.  – The Innovative Data Center Association and the Open Compute Project Foundation.

All the hard work is paying off because data centers are providing the basic infrastructure for the use of digital technologies that will contribute to the achievement of almost 60 percent of the 2030 climate targets, according to a Bitkom study. At EU level, Commission President Ursula von der Leyen said that her Green Deal was a  “man on the moon moment". It’s time we didn’t just build the “green rocket” but actually launched it into orbit. And we have to become carbon neutral with our own resources, not just on paper or with climate certificates.

Headquarter Frankfurt/Germany

Location Schiphol-Rijk/The Netherlands

Headquarter Frankfurt/Germany

Location Schiphol-Rijk/The Netherlands