A lot is said about how useful hydrogen could be. But the cost of transportation is a big problem.

In the past few years, there has been more and more talk about hydrogen. Many people see it as an important way to reduce the environmental impact of heavy industry and help countries reach their net-zero goals.

The green hydrogen industry, which is all about making hydrogen from renewable energy sources like wind and sun, has gotten a lot of attention and has some well-known backers.

They include German Chancellor Olaf Sch....