Energy for Antarctica: solar hydrogen as an alternative to crude oil?
Volkswagen Foundation funds feasibility study by HZB experts in artificial photosynthesis
The sun shines at the South Pole as well – and in summer almost around the clock. Instead of supplying research stations in the Antarctic with crude oil for producing the electricity and heating they need, solar hydrogen could be produced from sunlight in summer as an alternative. Hydrogen has a high energy density, is easy to store, and can be used as fuel when needed later without polluting the environment. An intriguingly simple idea - but one that raises many questions. Matthias May (HZB) and Kira Rehfeld (Heidelberg University) now want to examine how feasible this kind of solar fuel generation might be in Antarctica. The project is receiving financial support from the Volkswagen Foundation.
In addition to penguins, it is mostly researchers that live in Antarctica – collecting neutrinos, analysing glaciers and ice cores, and investigating how organisms survive the hostile conditions. Many research stations are operated year round and require heat and electricity, a large part of which is generated from crude oil. Environmental physicist Dr. Kira Rehfeld from Heidelberg University noticed how costly and laborious the transportation of crude oil to this region of the world is, however, when she took part in an Antarctic expedition. Even the smallest leaks are an enormous problem for the sensitive ecosystem, which is why strict precautions must be observed during transport.
Summer at the south
At the same time, the sun shines in Antarctica around the clock during the summer months and is very intense. Wouldn't it be possible to convert this solar energy into a form of energy that could be easily stored? Rehfeld played through this idea together with HZB expert Dr. Matthias May when she returned home.
Solar energy can be stored in hydrogen
May is researching complex material systems that use sunlight to split water molecules into oxygen and hydrogen. The hydrogen molecules store the energy from light as chemical energy. This chemical energy can in turn be converted into electrical power (electricity) or heat, with the hydrogen being converted back to just water with no harmful emissions.
And hydrogen can be stored in tanks
And a crucial point: hydrogen gas can be compressed and stored in tanks, so that the hydrogen stored in summer is available in the winter time as well when there is no sunlight. Rehfeld and May developed a project outline that they submitted to the Volkswagen Foundation under the Foundation’s "Experiment" programme. The project is now being funded for 18 months with a grant of 120,000 euros. May and Rehfeld will carry out a feasibility study during this period.
But does watersplitting work when it is cold?
They will have to develop approaches for solving a number of problems: splitting water with solar energy requires that photovoltaic thin-film semiconductors be combined with electrochemical reactions. However, while photovoltaic converters work quite well even at temperatures below zero, chemical reactions take place very slowly when it is cold. Moreover, modules for the production of hydrogen from sunlight must operate autonomously and be largely maintenance-free.
However, the initial solutions do not necessarily have to be particularly inexpensive. “The rise of photovoltaics also began with solar cells that were initially very expensive and could only be used in satellites”, argues May. ”Supplying the Antarctic stations with crude oil is also extremely expensive and in addition involves high risks to the environment. It is definitely worthwhile to think about alternatives“, stresses Rehfeld.
About the "Experiment!" funding initiative of the Volkswagen Foundation:
“Experiment” is oriented towards researchers who would like to test out a radically new and risky research idea. They are given the opportunity to gain initial insights as to the viability of their concept during an explorative phase. The funding provides a maximum of 120,000 euros and is limited to a maximum of 18 months.