Hydrogen Is Happening: Is This More Hype or an Important Part of Our Climate Future?
The targeted strategy of Germany’s hydrogen pilot projects and national hydrogen plan
There are few technologies that have been hyped as much for their climate-saving possibilities as hydrogen has been. In the early 2000's, hydrogen was touted as a futuristic fuel for cars, a way to reduce dependence on foreign oil, and literally a “way to save America.” Of course, few of these predictions came true, and, if anything, mostly worked as a political tool to avoid making actual energy and climate commitments.
So with multiple countries now working on national hydrogen strategies, it would only be natural to be a bit skeptical, given the history with the imagined silver bullet that was hydrogen. Yet hydrogen technology is being examined seriously as a potential tool for cutting the carbon from our energy use. Several countries that are making significant progress on deep climate commitments are each developing hydrogen plans: Germany released its much-awaited national strategy in June, France announced a rollout last summer, and the European Union is poised to release a plan for using hydrogen across the continent. Is this more hydrogen hype or a useful building block of decarbonizing energy use?
What Hydrogen Can Actually Do
It’s worth noting what hydrogen is and isn’t. It’s a gas that is rare in our atmosphere and doesn’t exist on the planet as a pure fuel that can be somehow mined. It can, however, be formed in a number of ways, some more polluting than others, and then transported and stored before being used. In short, it serves as an energy carrier from where it’s made to where it’s used, whether that is in the form of combustion or in an electricity-generating fuel cell. The process of transporting hydrogen and storing it needs to ensure safety; options include binding it to other molecules, such as carbon, to create a stable liquid fuel or storage medium. The most critical aspect for climate policy, however, is the way hydrogen is made.
Picking A Flavor: Gray, Green, Blue, or Turquoise
To date, most hydrogen has been made by stripping H2 out of fossil fuels, primarily natural gas. This means that a lot of waste carbon is generated, emitting as much as 10 tons of CO2 (!) into the atmosphere for every 1 ton of hydrogen produced (BMWi Energiewende Direkt). Used today for industrial processes, this approach is called ‘gray hydrogen.’
But we can also make hydrogen using 100% renewable energy. Electricity from wind turbines can be sent into an electrolyzer that simply splits water into H2 and O2. The same is possible using large-scale solar plants. This hydrogen, formed through renewables, is called ‘green hydrogen.’
In the middle of the spectrum lie two other methods derived from the gray hydrogen approach: first, using fossil fuels to strip out the H2 but using carbon sequestration to store the resulting carbon dioxide underground (aka the ‘blue hydrogen’ process), and, second, using fossil fuels and waste heat to capture the carbon in a solid form (making ‘turquoise hydrogen’).
But it’s green hydrogen, made from 100% renewables, that is the focus of climate policy. The promise of green hydrogen is significant: could we use renewable energy to produce a substance that can be shipped around, as a mobile energy medium? And could this be used where renewable electricity is not directly usable?
Putting Green Hydrogen into Pilot Mode Today
In July 2019, Germany’s Federal Ministry of Economy and Energy awarded grants under a new Reallabore der Energiewende program, designed to test out scientific concepts in real-world settings. These pilot projects now underway across Germany provide a fascinating look at some of the ways that a targeted use of green hydrogen could decarbonize our energy use. Awarding €200 million across 20 winning proposals, the program focuses on “low- or no-carbon hydrogen” as one of the key themes (BMWi Reallabore der Energiewende) and accelerates creative concepts proposed by a wide range of stakeholders.
A few of the selected projects will use green hydrogen to feed otherwise carbon-intensive industrial processes. In an industrial park situated across the Rhine from Switzerland, a modern low-impact hydropower plant will be used to power a 10 megawatt (MW) electrolyzer. The resulting hydrogen will be utilized in nearby factories, and the waste heat from the electrolyzer could be tapped into as well. On Germany’s northwest coast, a similar project will use up to 30 MW of wind power to create high-purity hydrogen and oxygen for industry.
Perhaps one of the most inspiring concepts is replacing coal with hydrogen in heavy industry; it would speak directly to this idea of using hydrogen where renewable electricity can’t be used directly. The H2Stahl project will be prototyping what could amount to a fundamental change for Germany’s steel industry, the largest in the EU. The project will replace part of the coal used for refining iron ore, by directly injecting 10,000 cubic meters of hydrogen per hour into the smelter. With this pilot expected to cut carbon emissions by 20%, the project has outlined how further tests could lead to deeper reductions.
Green hydrogen also offers a possibility of creating green fuels and utilizing waste CO2. For example, one of the selected proposals will capture the CO2 from a waste incinerator’s smokestack, combine it with hydrogen, and create a low-carbon methane fuel. Another is building a 50 MW electrolyzer to create liquid methanol for fueling vehicles — more stable than hydrogen and expected to be 90% lower carbon than conventional fuel.
Storage concepts are also being piloted, with two test sites in which two underground salt caverns will be used to store the hydrogen before use, both using wind turbines for generation.
Finally, hydrogen isn’t being tested in a vacuum: several projects aim to see how hydrogen could fit into urban environments to provide heat and vehicle fuel, focused on being an integrated part of energy-efficient districts. (A later post in this series will take a closer look at its role in local-level district energy systems.)
From Pilot to Practice: What Scaling Up Looks Like
In June, the German Ministry of Economy and Energy released the National Hydrogen Strategy, designed to start shaping the infrastructure that will be needed, and to provide researchers and industry with a more certainty on policy direction. Taking a huge step to fund this vision, the federal government announced in June that €9 billion of post-pandemic recovery funds will be devoted exclusively to hydrogen (Deutschlandfunk).
What exactly will this look like? The Strategy lays out a targeted, judicious approach of key sectors and principles to focus on (BMWi National Hydrogen Strategy):
Hydrogen can serve a few key roles. Building on some of the same pilot concepts, hydrogen is seen as an energy source, a storage medium, a way of coupling sectors that cannot use renewable electricity, an industrial input, and a way to capture and use CO2.
Only green hydrogen can be part of the long-term strategy. Nearly all of the hydrogen produced today (mainly for the chemical industry) is ‘gray.’ While those middle-ground options of blue and turquoise could be a short-term option, it’s made clear that 100% renewable hydrogen is the only long-term possibility. To boost domestic production, Germany expects to install 5 gigawatts (GW) of green hydrogen generation by 2030 and look at the regulatory framework that could encourage using excess renewable energy for hydrogen: this could include a waiver of typical taxes and surcharges for electricity or incentives to use wind in off-peak hours.
Focus on the sectors that are hard to decarbonize. There is a need to replace fossil fuels with renewables. We can replace coal and gas power plants with wind turbines and solar, but there are sectors that don’t rely on electricity, with liquid and gas fuels being particularly challenging. There are three sectors specifically identified:
· Heavy industry. ‘Green chemicals’ or ‘green steel’ (made using green hydrogen) are an important focus area and can be scaled up through quotas and financial guarantees.
· Very specific transportation modes. Namely, heavy-duty cargo transport could benefit from hydrogen in fuel cells; aviation and maritime fuels could utilize synthetic fuels made from green hydrogen. In other words, a jet or a cargo ship could be fueled by solar-powered fuels. Germany expects to work with the EU to establish a quota for ‘electrically-derived fuels’ in the aviation sector.
· Heating buildings (maybe). Given the importance of energy efficiency and the potential to use heat pumps and district energy, it’s clear that hydrogen is a last resort, once efficiency and electric heat pumps are fully utilized — and it’s not meant to simply replace all of the natural gas we currently use in our boilers.
Standardizing safe storage and transport is key. Hydrogen is currently shipped and stored in countries around the world. Nonetheless, establishing standard methods of storing, moving, and even metering hydrogen is an early action item. Potential new technologies include the use of more stable liquid organic molecules that carry hydrogen and reusing old natural gas infrastructure. This will be a major research area.
Thinking big: build a market inside and outside the EU. Working at the EU level will be key for a common market of hydrogen suppliers, with common standards. But, if we’re to think really big, there may be the opportunity to work with other countries to build renewable energy plants, generate hydrogen, and then ship it to wherever it’s needed. The Strategy identifies that this cannot undermine natural resources or domestic needs. Recent studies at Friedrich Alexander Universität present the possibility, and in fact the relatively easy feasibility, of Argentina using its extensive wind potential to generate hydrogen from water and ship it to the EU, or Namibia doing the same with solar, among other examples. (Grimm, dena Kolloquium)
The Scale is Significant
To be clear, the scale of the hydrogen need, even in these focus sectors, is still significant. Germany’s steel industry alone will need 100 terawatt-hours (TWh) of hydrogen each year to replace fossil fuels. That is a full 15% of all of the electricity generated in Germany (BMWi Strommarkt der Zukunft). The 5 GW of green hydrogen generation being built in the next ten years is equal to about 4% of all renewable energy plants in the country. As a result, it is clear that a country like Germany will continue to need to import energy, but largely in the form of green hydrogen.
Both the pilots underway and the vision for a scaled-up hydrogen economy are ambitious, to say the least, especially as we consider the idea of creating a global trade of hydrogen as an energy carrier.
However, it’s also clear that hydrogen is best intended for those applications that really need it. It is best used when other, more direct approaches to using renewable energy aren’t possible — it’s for the situations where electric vehicles, transportation mode shift, heat pumps, and building retrofits aren’t possible, or when those possibilities have been thoroughly utilized. For all of the talk about creating hydrogen-based synthetic aviation fuel, there is also a major political push to simply eliminate domestic airline travel for by expanding more efficient high-speed rail (Tagesspiegel), as France is already doing. Hydrogen can be a fuel, but why not cut down on the need for that fuel first? Similarly, for heating our buildings, the role of insulation and installing heat pumps will go a lot further and cost a lot less. Recent research has shown that heat pumps are 200 to 400% more efficient in providing heat than creating hydrogen-based fuels for home heating and then burning it in place of natural gas in our boilers (Agora Energiewende, Regulatory Assistance Project).
Using hydrogen will be an important part of getting to our climate goals, for those applications where it makes the most sense. So perhaps it’s best to think of hydrogen as the last piece of the pie that is economy-wide decarbonization. We’ll have the piece after the tastier slices of energy efficiency and delicious electrification have been all eaten up. And it’s only possible if the flavor of that last slice is green.
Nikhil Nadkarni is an urban planner specializing in climate, energy, and building decarbonization strategy. He is currently living in Berlin.