Interesting article. Thanks!
Some things that caught my eye:
Vox wrote:Johnson boasts that his electrolyzer can produce hydrogen at about three or four times the rate of electrolyzers with similar footprints, using about a third the electrical current. That represents a stepwise drop in costs.
So this guy is claiming to have a 9X to 12X improvement over commercially available products. Let's look at what a commercial product achieves in terms of efficiency today
GinerELX wrote:In testing at the US Department of Energy’s National Renewable Energy Laboratory, the efficiency of the stack ranged from 95% to 75% at current densities exceeding 30 kA/m2.
Since the theoretical efficiency limit for electrolysis of water is 120%, the biggest POSSIBLE improvement over today's commercially-available solutions is 1.26X to 1.6X. In other words, there is no possibility to improve them by 9X to 12X.
Regarding trucks, the following claims are made:
Vox wrote:HyTech’s offer to that market is pretty remarkable: it claims that its ICA can improve the fuel efficiency of a diesel engine between 20 and 30 percent,...
Vox wrote:The cost of transforming a dirty diesel engine to a relatively clean one: around $10,000 installed, which HyTech estimates will pay itself back in nine months through avoided fuel and maintenance costs.
If they can save even 20% of the fuel used, that would be a huge win, and could be very successful. Where does the hydrogen come from? If they are generating it on-board, then this sounds quite attractive.
Edit: I see that it does:
Vox wrote:A small, onboard electrolyzer produces more than enough.
The last question then becomes what happens to the truck's warranty?
I also like the idea of storing the hydrogen as part of a hydride, but the article implies that compression is a huge energy waster. I agree it wastes energy, but even without the compression, modern high-efficiency electrolysis uses nearly 50 kWh per kg of H2
GinerELX wrote:These exceptional efficiencies correspond to an energy consumption of less than 50 kWh per kilogram of hydrogen produced and are essential in building a compelling economic business case for the technology.
That much electricity will take a BEV approximately 200 miles. By comparison, fuel-cell vehicles will go about 1/3 that far on 1 kg of H2.
It's good to see people taking a fresh look at things. While some things don't seem to add up the truck idea looks like a really good one since the H2 and O2 are generated on-board. If even one of his ideas works out, it would be great!