Fuel Cells

[300mileclub]

Fast forward to 2015 and there are now 8 projects in the world storing megawatts of power by electrolysis of water. This helps carry wind power and solar installations through periods through periods when they are not generating electricity:

https://www.youtube.com/watch?v=B0Gh7gMKdRY

[300mileclub]

80% of H2 is made from hydrocarbon fuels by steam methane reforming (SMR); 20% comes as a by-product of chemical purification processes; and a negligible amount is produced by electrolysis - according to a 2007 paper on the subject.

[Timon]

Here is a video on how fuel cells work.