[lovemenot]

Hydrogen does have a lot of problems which other commenters here point out.

But if HyTech is to be believed, some of these problems are solved. Probably their most significant claim, is hydride storage at ordinary temperature / pressure with safe, practical, cost effectiveness in recovering that stored energy.

[phkahler]

HyTech doesn't solve the main problem with hydrogen - that there isn't any available as fuel, and it takes more energy to extract the hydrogen than you get back from burning it or even using it in a fuel cell.

The idea of injecting small amounts of hydrogen into a combustion engine to improve fuel economy is not new, but congrats if they can bring that concept to market. That would be a win, but is not the same as hydrogen as a primary fuel.

[nine_k]

It takes more energy to charge a battery than can be had back discharging it.

Does it make the battery in your mobile phone useless?

[dpark]

No one cares about the efficiency of the tiny battery in your phone. But if charging and discharging a Tesla used twice as much energy as burning gasoline directly then people would probably care.

At some level of inefficiency, an energy solution can indeed become useless at scale.

[noir_lord]

That depends though on a bunch of factors including base price of electricity, renewable potential and how easily hydrogen can be shipped.

There are a few developed countries I can think of that have vast renewable capacity but the distances between the optimum location for renewables make it impractical at present.

Also modern nuclear plants are an option if you want to produce vast amounts of electricity with a smaller carbon footprint than coal/gas.