UPDATED

They claim 8.33 kWh of energy for for less than 0.02 Euro. 8.33 kWh can be obtained from about 250 grams of hydrogen (33.33 kWh per kg of hydrogen).

After water and fill dirt, concrete is about the cheapest thing you can buy. In volume, can probably get 250 grams of concrete for about $0.02 Euro. I suspect the two undisclosed chemicals cost quite a bit more than concrete.

But let’s say this undisclosed combo of chemicals is as cheap as concrete and the water is free.

Can 250 gram of “something as cheap as concrete” plus any amount of water release 250 grams of hydrogen?

I’m dubious about that. And if the chemicals cost 10x the price of concrete, then it would have to be 25 grams of the chemicals releasing 250 grams of hydrogen. Very much more dubious.

As David Stonier-Gibson said “TANSTAAFL”, and there ain’t any such thing as Cold Fusion…but the process described in this article sure seems like Cold Fusion.