It’s no surprise that data centre providers are investing in sustainable solutions in response to growing demand from customers for long-term solutions to power their IT loads with clean energy. At the same time, many providers are striving to reach the sustainability goals to which they have committed. Businesses and governments around the world are determined to become carbon neutral by 2050 or earlier, which puts data centre sustainability firmly in the spotlight.
Today, hydrogen technology is one of the top sustainability innovations, and one of the most anticipated questions is whether it can be used to power data centres as an alternative form of energy. With this goal in mind, the UK government is even planning national subsidies to boost hydrogen production, and in August 2021 it launched the first-ever vision to kick start a world-leading hydrogen economy, which is set to support over 9,000 UK jobs and unlock £4 billion investment by 2030.
However, the embryonic hydrogen industry has not yet been able to overcome the investment, sustainability and cost issues related to data storage use cases.
The growing urgency for sustainable power alternatives is both driving hydrogen energy solutions for the data centre and incentivising investment. Data centres and IT systems not only require consistent energy continuously, 24/7, but are now very committed to reducing their carbon footprint and therefore are turning towards renewables and looking for alternative sources of energy.
Emerging hydrogen fuel cell technologies are transforming chemical energy from fuel to electricity as they offer backup loads and a reliable and sustainable off-grid or primary power source for combined power and cooling applications, grid and microgrid support.
Fuel cell opportunity
A tech consortium of seven companies chosen by the Clean Hydrogen Partnership – Equinix, InfraPrime, RISE, Snam, SolydEra (former SolidPower), TEC4FUELS and Vertiv – is working to develop a next-generation fuel-cell platform for data centres.
Vertiv is developing a UPS and battery solution to go with solid-oxide fuel cells, which will be used to provide resilient and clean primary power to data centres. This will invert the current approach of using grid energy as the backup power source. The consortium, called EcoEdge PrimePower (E2P2), aims to implement natural gas solid oxide fuel cells (SOFC) as a prime power application to pave the way for the use of green hydrogen for fuel cells for both backup and prime power systems.
SOFCs use a ceramic compound as the electrolyte. They operate at high temperatures (800-900°C /1,472-1,652 F), which eliminates the need for a precious-metal catalyst, but it increases start-up and shutdown times, making them better suited for continuous duty applications. Another benefit is that they are also more flexible when it comes to fuel input because they mainly use natural gas, with some designs able to process pure hydrogen. SOFCs have a high operating efficiency that can be further enhanced by capturing and reusing the heat it produces.
Some forward-looking companies are also considering proton exchange membrane (PEM) fuel cells as backup power sources to substitute diesel generators in data centres. PEM technology uses hydrogen as their fuel source and features a solid polymer electrolyte that brings high power density that enables a smaller footprint when compared to fuel cells. To generate electricity, they require only hydrogen and oxygen from the air, and they operate at relatively low temperatures (up to 80 °C / 176 degrees F). Because they don’t have to heat up to the high temperatures required with SOFC, they can start quickly, making them suitable for backup power applications. To separate hydrogen’s electrons and protons, PEM fuel cells require a noble-metal catalyst such as platinum, which requires special safety safeguards due to its toxicity.
Although hydrogen fuel cell technology is not new – it has been around since the 1960s and today is produced on an industrial scale for the automotive sector – based on current fuel cell technology and other developments in data centre power environment, it is possible to imagine a future in which fuel cells provide data centres with clean primary and secondary power.
As technology and innovation stand today, PEM fuel cells would provide backup power, whilst SOFCs would be used for primary power. In the event that not all SOFCs are capable of being refurbished to operate with pure hydrogen, PEM fuel cells may be able to provide primary power.
A greener future
Many organisations in the digital infrastructure industry are committed to advancing the sustainability of their operations. Some are leveraging their extensive experience in AC power systems to design and develop an integrated fuel cell power module. For example, Vertiv is already planning to develop standard UPS systems that are capable of interacting with this green technology.
The path to deploying fuel cells as a primary, carbon-free power source for data centre applications is longer than that of backup power applications, largely due to current hydrogen distribution limitations. But there is progress on that front too, and natural gas-powered fuel cells can be used as a stopgap solution. This will reduce emissions and provide other benefits whilst hydrogen distribution is expanded.
The waste product of a pure-hydrogen fuel cell is water vapour, which technically means zero emissions. In the real world, however, emissions are produced in the manufacture of the technology and in the processes, including transportation and storage. Therefore, hydrogen is classified according to how it is produced as the type of production process involves a certain number of emissions.
The many colours or hydrogen
Fossil fuel reforming produces brown hydrogen. Likewise, blue hydrogen is produced with fossil fuels, but CO2 is captured during the process and pink hydrogen is produced by using nuclear energy to electrolyse water. Another option is green hydrogen, which is produced by electrolysis of water with electricity generated by renewable sources like solar photovoltaic or wind. The introduction of hydrogen energy into the mix will have the effect of reducing emissions because it reduces the use of fossil fuels whilst using a fuel with much higher energy density.
As of today, there are few applications with a precise and green lifecycle of hydrogen, so it is difficult to have detailed data about its lifecycle. However, we can say that compared to the current situation, the use of hydrogen definitely brings an improvement; in comparison to the current power grid layout, which uses diesel generators as backup and batteries for short-term discharge, hydrogen has few technological rivals when it comes to lower-emission and compact footprint systems.
There are some challenges
When looking at hydrogen as a green energy alternative, there are some considerations/limitations. Hydrogen must be stored under pressure or at very low temperatures, which is expensive. Regulation is also an obstacle; other industrial sectors (glass and food production, for instance) already use hydrogen, but a new legal framework is needed, especially for data centres.
Additionally, the near invisibility of hydrogen flames and the possibility of burns pose some safety concerns. Hydrogen, however, despite its known safety hazards, is a safer fuel than gasoline and diesel when handled responsibly. When hydrogen is released, it rises and disperses rapidly, thus reducing the risk of ignition at ground level. Plus, hydrogen is non-toxic (unlike many other fuels).
The use of fuel cells is unlikely to be adopted at a rapid pace due to the challenges mentioned above. There will likely be a steady increase in the use of the technology. In the short term, fuel cell systems might gradually replace diesel generators for back-up power. Then as hydrogen costs decrease (by 2025, the cost of green hydrogen is expected to drop from $6 per kg to $2 per kg as the market grows) and single proof of concepts demonstrate the feasibility of fuel cell based systems, we could see the first primary power applications.
Transportable hydrogen, easy to use and store at a reasonable price are all prerequisites for fuel cell technology to become commercially viable. In an effort to reduce cost constraints in fuel cell technologies, organisations should work closely with different manufacturers and suppliers of fuel cells. Although more investment and research is needed, fuel cells are undoubtedly set to power a long-term clean energy transition for the data centre industry. Indeed, it’s now crucial that a clean, viable power source is found as data consumption grows at an increasing pace.
Looking ahead…
As reported by the International Energy Agency (IEA), data centres constitute approximately 1% of global electricity consumption, and this figure is expected to grow further over the coming years.
With this in mind, it is even more vital to accelerate the transition to a more sustainable future, which can only be achieved through the development of innovative technologies, such as fuel-cell solutions that offer early evidence of providing sustainable electricity for the digital age.
For operators seeking to achieve carbon neutrality, fuel cells are one of the most promising solutions. By utilising clean hydrogen, PEM fuel cells are capable of reducing CO2 emissions from maintenance checks on generators and from operation during power outages. In the near future, commercial fuel cells based on PEM technology are likely to be available in this application.
Hyperscale operators that have taken a leading position on carbon reduction are likely to be the first to utilise fuel cells to replace or supplement diesel generators. Nevertheless, as fuel cells develop, they will become an increasingly attractive solution for a wide range of data centres.
A key component of advancing the use of fuel cells in data centre applications is the delivery of critical infrastructure solutions that enable effective use of fuel cells and support additional functionality, including peak shaving, renewable energy use, and grid balancing services.
