Featured Toyota and Hino Truck to Jointly Develop Class 8 Fuel Cell Electric Truck for North

https://www.daimler-truck.com/innovation-sustainability/efficient-emission-free/mercedes-benz-genh2-fuel-cell-truck.html

Looks like Mercedes is back in the game.

 

2 thoughts from the read -
- concept .... good luck w/ that MB
- liquid hydrogen ..... ⅓ of hydrogen's usable energy is spent in refrigeration (much less reformation energy sources) - bringing its gas down to Sub-Zero temps .... and what kind of boil off losses.
Of course Nasa uses liquid hydrogen .....



NASA costs were so great (even for government money) - it required huge cutbacks in their program budget.
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I think you need to understand how expensive 10,000 psi hydrogen is to pump in large quantities and liquid makes a lot more sense.

According to the DOE, it is going to take 2-8 kwh to compress and pump each kg of hydrogen. But if a station is supplied remotely its going to get liquefied and trucked in if its not close enough to be supplied by pipeline. To liquify and pump hydrogen theoretically doe says it takes about 5 kwh/kg, but in real life they estimated from fueling 10 Kwh. Let's say without transport costs the 10,000 psi hydrogen supplied by liquid would take that same 10 kwh. If an electrolyzer is 80% efficient (that's about as good as we get right now) then it will take 50kwh of electricity to make 1 kg of hydrogen. That would mean the 10,000 psi hydrogen would take 52-58 kwh/kg, and liquid 60 kwh/kg. Nikola estimated you need 80 kg to go 700 miles and had a demo (who knows if it was faked) that could fill it in 15 minutes. DOE says that leakage from liquid is about 1% a day, so if it takes you 2 days to use your 80 kg you lose 2% making it take maybe 61 kwh/kg. Using a pressurized tank and a compressed tank on a truck will lose even less.

The advantage of liquid is obvious. The station does not need to compress and cool for each load, its liquid already. Liquid can be fueled much faster meaning less expensive equipment at the station. On board the truck needs only about half the volume of tank and the tank is much less expensive.

 

The BMW Hydrogen 7 - Wikipedia had a 45 gallon liquid hydrogen tank. Typical vent rate would have it empty in 10 to 12 days while parked. Liquid hydrogen isn't very practical for personal cars that can be left park for some time. Imagine how much would have been vented with the pandemic if we were using liquid hydrogen instead of gasoline.

On the other hand, trucks generally aren't parked for extended periods, and they have chassis space for more insulation on the tank.

 

With 45 hydrogen stations in operation, California continues to lead the way in hydrogen infrastructure development in the United States and this gap will only widen with 36 more stations to be built shortly with the help from the California Energy Commission (CEC) and Volkswagen Environmental Mitigation Trust Funds. The latter is contributing $5 million. This is the first large California investment in the hydrogen infrastructure since the previous solicitation in 2015.