Here's a fun little exercise with the Toyota Mirai.
Read the spec sheet, and read the wikipedia article. They claim the thing can hold 5 kg of H2, at 10,000 psi.
Look into how big the tanks are.
The math will show that at that pressure, taking up that much space, you can fit no more than about 3.7 kg of H2 in there.
The difference between the diesel emissions and mileage scandal and the Mirai is that they actually made the math work with the former, as well as large enough scale for people to care.
Read the spec sheet, and read the wikipedia article. They claim the thing can hold 5 kg of H2, at 10,000 psi.
Look into how big the tanks are.
The math will show that at that pressure, taking up that much space, you can fit no more than about 3.7 kg of H2 in there.
The difference between the diesel emissions and mileage scandal and the Mirai is that they actually made the math work with the former, as well as large enough scale for people to care.