"It is feasible to use Norways vast hydro resources as a storage solution for balancing Germanys solar and wind power surpluses based on projections to 2030," asserted Atle Harby, SINTEF Energy Research. He made the statement as he presented the results of his research teams simulations of the impact of storing surplus solar and wind energy from Germany in Norways hydro pumped storage.
His simulation showed that there will be extended periods of time when Germany produces a surplus of solar and wind energy, but also periods of up to seven days where renewable energy production is negligible. The idea is to balance production and consumption mismatches with the Norwegian large-scale storage solution.
Harby added that it is possible to store up to 20 gigawatts of electricity at a reasonable cost per megawatt hour for Germany, without having to add any new damns in the future, or causing erosion and ice buildup in existing dams. Other environmental risks, such as impact on wildlife, have yet to be explored, however. Furthermore, the cost calculations did not include the investment required for grid connections, that is, laying new underground cables for a direct connection between the two countries, as well as the necessity for a North South transmission infrastructure build-out in Germany.
"The regulatory and legal frameworks for the hydro storage solution from Statkraft are in place," continued Marianne Holmen, vice president of the Europe’s Renewable Battery project at Statkraft, when she made the case for the state-owned utilitys solution. Holmen underlined the allied interests in such a project, saying that she has studied wind power output in particular and noted the variations over a month long period, positing that the Norwegian solution can "handle this exact scenario".
Besides the infrastructure investment, long term inter-governmental and market contracts are essential for the success of the effort, according to both Harby and Holmen.
Green battery competing with hydrogen storage
The Norwegian solution is one of two leading technologies proposed for large-scale storage and presented at the Solarpraxis Energy Storage Summit by international experts. The other is hydrogen storage.
Hydrogen is the less mature of the two, less efficient, and potentially more expensive. But some experts see that merely as a need to come down the learning curve at speed. The hydrogen approach is being researched in various centers in Germany and Europe, in the multi-participant Power2Gas effort, as well as in projects promoting the creation of a hydrogen mobility solutions, including hydrogen-powered cars and buses.
Both large-scale solutions are vying for a position to win a race that is just starting now and wont really gain momentum for another eight to ten years, perhaps longer, depending on the penetration of solar and wind in Germany. "If the Norwegian project goes through, it can take care of Germanys large scale renewable energy storage requirements. We wont need the hydrogen path," said Olav Hohmeyer of the University of Flensburg, speaking at the final panel discussion of the conference.
His colleague, Andreas Gutsch of the Karlsruhe Institute of Technology, was more circumspect, saying that what will win the race depends on which technology develops a mass market first. "Be it batteries, hydrogen, or another technology which one will become cheaper, sooner, faster due to volume sales, that is the question. And it is not only Germany that influences that outcome. It is something that is determined by the global market."