On particularly breezy, sunny days, Germany generates more renewable power than its grid can handle. To prevent grid overload, wind farm operators must curtail or suspend production. If that doesn’t solve the problem, grid operators have to pay the grids of neighboring countries to take the power off their hands. In other words, Germany is heavily subsidizing renewable energy and then selling it for a loss. Not an ideal situation.
It could be avoided if electricity could be stored on a large scale. One option is big new batteries that can store several megawatt-hours of output. Another option – one that has the advantage of utilizing existing infrastructure – is to use surplus renewable power to run electrolysis equipment that transforms water (H20) into green hydrogen (H2).
Help from hydrogen
Hydrogen, whose combustion properties are similar to those of natural gas, can be injected in large quantities into Germany’s network of gas pipelines and underground storage facilities. It could then be transported to all corners of the country to be used for space heating, for industrial processes, or to generate power on cloudy, windless days. Moreover, renewable energy generated in the summer could be stored and used to heat homes in the winter.
Looking further into the future, green hydrogen has enormous climate-protection potential. That’s because it could be combined with captured carbon to produce carbon-neutral fuels and inputs that would help hard-to-decarbonize industries – chemicals, steel, and marine and air transport – move toward carbon neutrality. Indeed, hydrogen “is the only fuel that can decarbonize most sectors,” emphasizes Andreas Schierebeck, the CEO of Uniper, the Düsseldorf-based energy company that funds Debate.Energy. “It can be produced where conditions are technically and economically favorable, stored in large quantities, and transported across continents to be used where necessary.”
Currently, however, green hydrogen is fairly expensive. That’s why, Dr. Veronika Grimm, Professor of Economic Theory at Erlangen-Nuremberg University, points out that “it’s important to invest now in green-hydrogen production capacity and to reduce costs by scaling up production. Green hydrogen has to become cheaper, which is typically the result of increasing the scale of production.”
Scaling up is precisely what Uniper aims to do. The company, which already has extensive experience operating small green hydrogen production plants, plans to partner with other companies to build industrial-scale green-hydrogen plants, in one case at a location in eastern Germany. The latter project has been short-listed for funding from Real-Life Laboratory, Germany’s program to accelerate the development of innovative technologies for a cleaner energy future. More support for hydrogen will come from the National Carbon Strategy that Germany announced in June 2020.
Holstein’s hydrogen hopes
In Schleswig-Holstein, Germany’s northernmost federal state, the problem of surplus renewable power is particularly urgent. A roughly 100-kilometer-wide isthmus situated between the North Sea and the Baltic, Schleswig-Holstein is flat, blustery and, not surprisingly, has a lot of wind farms. In 2019 Schleswig-Holstein generated about 3.75 terawatt-hours of surplus electricity, enough to power all 1.9 million households in the state for a year. If its wind farms weren’t frequently taken offline to prevent grid overload, it would’ve produced even more.
Schleswig-Holstein’s has decided that hydrogen can help. Its first wind-powered green-hydrogen production plant opened in August 2019 in Brunsbüttel in the southwest corner of the state. At peak output it can produce 450 cubic meters of hydrogen an hour, enough to propel a fuel-cell vehicle 4,000 kilometers. But Brunsbüttel is just the beginning. In October 2020 Schleswig-Holstein unveiled its own hydrogen strategy, which includes €30 million in funding to innovative projects through year-end 2023. The aim is to harness more of the state’s abundant renewable resource and to become a leader in hydrogen production.