@nealf I have one big reason to doubt their hydrogen generation cost estimates:
If they were really doing it 50-80% cheaper than anybody else could, they should just be selling the hydrogen.
Global hydrogen production is about $140 billion USD per year, and if they are
really half the price, they should be able to carve out a huge chunk of that market in short notice. They might not be able to compete with those that generate hydrogen as a byproduct, but they could capture almost the entire "on-purpose" hydrogen generation themselves.
There's no need to futz around with building cars and trucks. There's a reason XOM has 4x the market cap of GM.
I don't have the Mech.E. background to verify the rest of what you're saying. My physics undergrad allows me to understand the words you're saying, but not enough to check the numbers myself.
But that's the one thing that really stuck out to me, from a business perspective. If you can produce hydrogen
that cheaply, then that's your business right there. Maybe start making trucks after. Use the cheap hydrogen profits to bootstrap your truck business.