Underground hydrogen storage
Underground hydrogen storage is the practice of hydrogen storage in underground caverns,salt domes and depleted oil/gas fields. Large quantities of gaseous hydrogen have been stored in underground caverns by ICI for many years without any difficulties. The storage of large quantities of hydrogen underground in solution-mined salt domes,aquifers or excavated rock caverns or mines can function as grid energy storage which is essential for the hydrogen economy. By using a turboexpander the electricity needs for compressed storage on 200 bar amounts to 2.1% of the energy content.
The Chevron Phillips Clemens Terminal in Texas has stored hydrogen since the 1980s in a solution-mined salt cavern. The cavern roof is about 2,800 feet (850 m) underground. The cavern is a cylinder with a diameter of 160 feet (49 m), a height of 1,000 feet (300 m) and a usable hydrogen capacity of 1,066 million cubic feet (30.2×106 m3), or 2,520 metric tons (2,480 long tons; 2,780 short tons).
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