Green hydrogen is used to store renewable electricity that cannot feasibly be stored any other way. There are some small Scottish islands producing so much wind power that the UK national grid cannot take it all. There are no battery packs or hydroelectric facilities that can store it. [So they’ve been producing hydrogen instead.]((https://www.bbc.com/future/article/20190327-the-tiny-islands-leading-the-way-in-hydrogen-power)

It might not be the best solution anyone could ever wish for. But it is the only currently available solution for some storage problems and for a lot of heavy transport. And a better solution for cars than batteries. If you could wave a wand and abolish private vehicles, you should do so. But you can’t. You can make electric vehicles a lot lighter and a lot less polluting while you work on getting rid of them in this real world that we live in.