Hydrogen storage
Hydrogen held as compressed gas, liquid, in salt caverns, depleted gas fields or metal hydrides.
Storage · Chemical · No. 86
- Storage
- Duration: Days to seasons
A single salt cavern can hold up to 6,000 tonnes of hydrogen, and one British cavern has been working since 1972.
Chart: Illustration: Hydrogen storage
Where it comes from
Chart: Map of where it comes from
Hydrogen made with spare power is squeezed to 350 to 700 bar, chilled to about -253 C, pumped into caverns, or bound to a metal or liquid.
Three things to know
- Hydrogen burns from about 4% in air with an almost invisible flame, and it leaks through tiny gaps.
- Bigger caverns are much cheaper per kilogram: about USD 25/kg at 1,000 tonnes against USD 95 at 100 tonnes (calculated).
- Releasing hydrogen from an organic liquid carrier takes about 11 kWh of heat per kg, roughly a third of its energy.
The journey
- 1 ElectrolysisSpare power splits water into hydrogen
- 2 DensifyCompress, liquefy or bind to a carrier
- 3 StoreTanks, salt caverns or depleted gas fields
- 4 ReleaseDecompress, warm or heat the carrier
- 5 UseTurbine, fuel cell or industrial feedstock