Hydrogen: Fueling Innovation in the Data Centre
Thu 25 Feb 2021
Hydrogen innovation for data centre applications is making great strides, writes Nicole Cappella
Over the past decade, the number of internet users has doubled while global internet traffic has increased 3x year-over-year. In 2019, data centres accounted for approximately 1% of total global energy consumption, or 200 TWh/year.
The good news is that even with increased demand, total energy consumption by data centres has remained remarkably flat. This has been due in large part to advances made in technology and design that have improved energy efficiency in data centres.
But as demand for data centre services continues to grow, and more companies make pledges to go green, controlling energy consumption and seeking out alternative energy sources is a top priority. In addition to popular renewables like solar, wind and hydro power, one area that data centres are exploring is using hydrogen fuel cells as an energy source.
How hydrogen fuel cells work
Hydrogen is readily available all over the planet but is generally found in combination with another element like water (H2O).
Pure hydrogen is needed for fuel cells, which means the elements must be separated. Then, the pure hydrogen combines with oxygen in a fuel cell, releasing water and electricity.
Benefits as an energy source
Hydrogen separation is a zero-emissions process, making it a far better option environmentally than traditional fuels. For example, diesel exhaust contains environmental contaminants including nitrogen oxide, benzene, arsenic, formaldehyde – more than 40 known pollutants, all in all.
Crude oil is processed in refineries to create usable fuel. But oil refineries cause air pollution, releasing gasses including nitrogen oxide, carbon dioxide, methane, chlorine, and more.
The fact that hydrogen can be used without generating harmful emissions is one factor in its favor, but to make it a green energy source it must be produced cleanly as well. Because of this, companies are currently researching different methods of production to obtain pure hydrogen in a clean, green way.
Keppel and Mitsubishi Heavy Industries recently announced that they were exploring a steam methane reforming process for hydrogen, in an effort to create a carbon-neutral process.
Oil and gas dependencies and issues have contributed to international issues over time, influencing the delicate balance of relations between countries. An in-country source of renewable energy, like hydrogen, would be an advantage for a country, making them less vulnerable to outside influences. Over 30 countries now have a national hydrogen strategy and budget in place, with 228 production and usage projects in the pipeline.
Challenges of hydrogen as an energy source
It takes a high volume of hydrogen to generate energy, which presents a challenge for storage. Natural gas provides 3.2 times more energy than hydrogen at equal volumes, for example. Storing hydrogen becomes complicated, because it requires high pressures, low temperatures, or chemical processes to make it compact enough for storage.
Companies are exploring the use of hydrogen storage tanks for other use cases, but these would not suffice to store enough energy needed to power your typical data centre. It’s more likely that data centres will be proximal to the site of generation, such as is being researched by Keppel and Mitsubishi Heavy Industries.
Possibly the greatest challenge to widespread adoption of hydrogen fuel cells as an energy source is creating the infrastructure required for distribution and delivery. A centralised source would reduce production costs but increase the need for an extensive distribution network.
On the other hand, a distributed production network would reduce the costs of infrastructure and transportation, but increase production costs as it would require additional processing stations.
Overcoming these challenges to create a viable energy source for data centres could go a long way toward helping businesses to reach environmental goals, including reducing carbon footprint and powering data centres with renewable and sustainable energy sources.
Most data centres today use diesel generators as a backup system for power outages and interruptions in service. Batteries are a part of the system as well, bridging the gap between a power failure and generator startup – usually a 30-60 second delay.
Last June Microsoft ran a successful test of a hydrogen fuel cell system at a data centre, with a 48-hour endurance test of a 250-kilowatt fuel cell system. This system would provide sufficient energy to power 10 racks of data centre servers.
A successful endurance test for an extended period is promising for companies that are looking to replace diesel generators with cleaner, more efficient energy sources.
According to Microsoft, the next step will be to purchase a 3-MW hydrogen fuel cell system. This is approximately the size of the diesel generators currently in use at Azure data centres, so a successful endurance test would be a positive step in replacing the diesel systems altogether.
Data centres that currently use diesel generators for backup power in the case of service interruption or power outage stand to gain the most from switching to hydrogen fuel cells.
Reducing dependence on diesel, a fuel that contributes to pollution in both production and use, and replacing it with a clean, sustainable energy source is one way that data centres and big tech companies can reach their environmental goals. Overcoming the challenges of infrastructure, storage and distribution may take time, but recent advancements are promising.