Swedish steel maker SSAB, LKAB and Vattenfall are inaugurating HYBRIT’s pilot facility for fossil free hydrogen gas storage at Svartöberget in Lulea in Sweden. The rock cavern storage facility is the first of its kind in the world. The inauguration ceremony marks the start of the two-year test period, which will run until 2024. The hydrogen storage facility will play a very important role in the overall value chain for fossil-free iron and steel production. Producing fossil-free hydrogen gas when there is a lot of electricity, for example when it is very windy, and using stored hydrogen gas when the electricity system is under strain, will ensure a steady production of sponge iron, the raw material behind fossil-free steel.The pilot plant has a size of 100 cubic meters. At a later stage, a full-scale hydrogen gas storage facility measuring 100,000 to 120,000 cubic meters may be required, in which case it will be able to store up to 100 GWh of electricity converted to hydrogen gas, which is sufficient to supply a full-sized sponge iron factory for three to four days.The technology for storing gas in a lined rock cavern is well proven and has been used in southern Sweden for about 20 years for storing natural gas. Now the technology is taking a step forward by the development for storage of hydrogen gas, and the storage facility will also be used more dynamically, being filled and emptied at pace with the hydrogen production.HYBRIT initiative was launched in 2016 by the three owners; SSAB, LKAB and Vattenfall. Using HYBRIT technology, SSAB can reduce Sweden’s carbon dioxide emissions by 10 percent. SSAB, LKAB and Vattenfall invest a total of SEK 259 million in the hydrogen storage itself, divided into three equal parts, and the Swedish Energy Agency contributes with SEK 72 million.