Hydrogen storages important foundation for solar PV expansion in Europe – German govt scenarios

The construction of hydrogen storage facilities beyond the existing caverns is crucial for the energy system of the future, especially as a basis for solar photovoltaics (PV) expansion, according to energy scenarios for 2045 commissioned by the German economy ministry (BMWK), reported Tagesspiegel Background. "As the amount of energy generated by PV fluctuates greatly depending on the season, hydrogen storage systems are used to shift the amount of energy from summer to winter," says a presentation on the so-called "long-term scenarios," which have become an industry standard for assumptions about the most efficient decarbonisation of the entire energy system. Europe would have a storage capacity of only 42 terawatt hours (TWh) if just existing cavern facilities were used, compared to total capacity of 278 TWh with additional facilities. This would mean that only around 1,600 gigawatt (GW) of solar PV capacity would be built, instead of 1,900 GW. "A development with very little hydrogen storage is very risky and partly outside the realistic solution space," says the document.

Hydrogen made from renewable electricity is increasingly seen as a silver bullet for sectors with particularly stubborn emissions, such as heavy industry and aviation. But at the same time, Germany aims to use it as a fuel to store intermittent wind and solar energy. During especially sunny or windy days, excess electricity could be used in electrolysers to split water into oxygen and hydrogen, which is then put into storage facilities for later use, for example in hydrogen-fired power plants. Based on existing technologies, batteries can partly be used to balance out renewables feed-in in the short term, but hydrogen is better suited for this large-scale seasonal storage.