Yamaha unveiled the world's first hydrogen-powered outboard engine for recreational boats at the Miami Boat Show, built with Roush and Regulator Marine.
Yamaha unveiled the world's first hydrogen-powered outboard engine for recreational boats at the Miami Boat Show, built with Roush and Regulator Marine.
Decades of funding from the Japanese government - dating back decades, to a time pre-dating the development of the lithium-ion battery, to a time when it was thought that the only way out of toxic Tokyo smog was to go the hydrogen-fuel-cell route. Japanese culture is loath to ever criticise or admit being wrong, so the whole government-sponsored thing continues, while the rest of the world mostly goes a different direction.
In the rest of the world, it's at least in part a "climate action delaying" action: Criticise EV development for not having the infrastructure (which is mostly wrong - we don't have "enough" infrastructure, but we can piggyback on top of what we've already got quite easily - I just need to look outside to see what's in my driveway) and promote "Fill up in 5 minutes!" on hydrogen while failing to mention that green hydrogen production (note: GREEN hydrogen made from wind and solar - not fossil fuel masquerading in disguise like 98% - 99% of hydrogen is today) and distribution and retailing infrastructure is as close to zero as makes no difference, and you CANNOT piggyback on top of any infrastructure that we've already got - it's start from scratch. So, by promoting something that seems attractive as being only a few years off into the future while actually being in "never going to happen" territory, it delays implementation of something that can more-or-less, if perhaps imperfectly, be done today.
That said, boating is a tough application for EV conversion. Those powertrains tend to run at high load for long periods of time. Still ... if you calculate the total weight and volume of hydrogen, including the weight and volume of its storage tanks (the weight of the storage tank BY FAR exceeds the weight of the hydrogen contained within, due to the need to store it at +/- 700 bar pressure) ... It's rather unattractive. Good batteries are probably better on a total volume and weight basis ...
Apparently a Toyota Mirai (hydrogen fuel cell vehicle) uses about 0.8 kg / 100 km of hydrogen. (similar size petrol car would probably use about 8 litres of petrol weighing about 6 kg)
Density of hydrogen at STP (1 atmosphere and 25 C) is 0.09 grams per litre
At 700 bar (700 atmospheres) that density would be 63 grams per litre, so that 0.8 kg of hydrogen would take up about 12.5 litres of space. That's 50% more volume than the petrol takes up, BUT, the problem is that this is at 700 bar pressure, which severely restricts the shape and size of the containers that are required.
Minor digging finds that a typical hydrogen storage tank used in an automotive application has a capacity of 4 - 6 kg of hydrogen and weighs about 100 kg. And they have to be a cylindrical shape with rounded ends - not the almost-arbitrary shape of a normal automotive fuel tank (or, for that matter, a battery pack).
With today's batteries, 100 kg would be around 24 kWh, and we haven't even talked about the weight of the fuel cells themselves, the battery pack that fuel-cell vehicles also contain, and all the stuff around all this to make it work. Or the crash safety provisions ...
Batteries are still behind fuel cells in terms of "energy content per total kg of system weight" ... but not by an enormous factor, and they're catching up.
That said, boating is a tough application for EV conversion. Those powertrains tend to run at high load for long periods of time. Still ... if you calculate the total weight and volume of hydrogen, including the weight and volume of its storage tanks (the weight of the storage tank BY FAR exceeds the weight of the hydrogen contained within, due to the need to store it at +/- 700 bar pressure) ... It's rather unattractive. Good batteries are probably better on a total volume and weight basis ...
Gasoline or diesel is still a better choice in marine applications and will be for the foreseeable future.
Cover the top of your boat in solar panels and maybe you could run the blender...
... but but...
Making a hydrogen powered thing is the easy part. The hard part is getting economical hydrogen to put in the tank.
So far making hydrogen requires more energy put into the process than comes out. Start cracking water into hydrogen using geothermal energy in Iceland/Greenland might work... but then how do you transport the gas to market?
Energy "wise" petrol will always win... the problem is emissions. Ocean going freighters contribute a HUGE portion of emissions... like 10%
I think nuclear is our only answer in BIG boats; freighters, ocean liners.
US military is probably the biggest emitter out there
So far making hydrogen requires more energy put into the process than comes out.
That statement is true, but not only that, thanks to the laws of thermodynamics, that statement will always remain true from now until the end of time. Laws of physics aren't possible to be violated the way arbitrary laws of mankind can be.
It is possible, or rather likely, that various improvements in technology will eke out improvements in efficiency from the various steps in the process, but they are likely to only be marginal ... and there are many steps. The electrolysis is only the first one. Then you have to get the hydrogen into a form in which it is practical to transport it. Compressing a gas to 700 bar pressure requires energy, no matter how efficient your compressor is (thermodynamics, again), and it's quite significant in this case due to the low density of hydrogen, which means you have to do a lot of compressing. And, there's no practical way to recover the energy of compression in a small-scale application when it comes time to use the hydrogen for something. Sure, if you had a stationary plant on a megawatt scale, you could heat it up and run it through a turbine to recover the energy of compression, but that's not practical for an automotive scale. The best you could do is to use the expansion of the hydrogen as the means of air-conditioning the cabin in cold weather. Or you could build a fridge/freezer into the vehicle (Toyota has a history of doing that!) and use the expansion of the hydrogen to operate it. But eking out that small savings in the HVAC system is peanuts compared to the operation of the whole vehicle.
Fuel cells, right now, are 50% - 60% efficient. One of the limitations is that they have to run hot enough to eject the water as steam. Heat loss. Energy lost. Again, perhaps you can recover some of it for HVAC, but it's peanuts compared to the energy taken to operate the whole vehicle.
meanwhile ... today ... charging and discharging a lithium-ion battery is 85% - 90% efficient ...
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