Over the past week, the development of alternatives for Russian natural gas has changed from a part of climate policy to a wartime priority. In that effort, the potential for the use of hydrogen is being even more intensely examined.

Yes, hydrogen can be burnt while only producing water vapour rather than carbon product (although most present forms of making the fuel require carbon-emitting processes). Hydrogen has the potential to replace the short-term electricity grid storage provided now, on a small scale, by stationary lithium ion batteries.

On the basis of much of the material summarised for public debate, a transition to a hydrogen economy makes sense. Hydrogen could, hypothetically, be used as aircraft fuel or for heavy vehicle and ship transport. Some natural gas pipeline operators are studying hydrogen shipment through existing networks.