[Richard230]

An article in my newspaper today said that the H2 fueling stations in California are not very numerous and are not being maintained very well. There are roughly 12,000 H2-powered cars on the road in California. And H2 fueling stations are hard to come by. There are only two in Sacramento (where the reporter lives), 62 in the entire state, including 22 in LA, 12 in Orange County, one in San Diego County, ten in Santa Clara County and three in San Francisco. The article says that not only are H2 stations hard to find but in the Sacramento area the fueling stations have been down almost as much as they have been up, according to John White, a longtime environmental activist who drives a Toyota H2 car. "That is not a good situation." he says.

Here is something that I didn't know: The article says that another problem with H2 is the "exorbitant cost of filling the tank", around the equivalent of $16 a gallon or higher. State Senator, Josh Newman, D-Fullerton, drives a H2 cars and loves it, but he says that "it's a challenge to keep it fueled."

[NVDucati]

An article in my newspaper today said that the H2 fueling stations in California are not very numerous and are not being maintained very well. There are roughly 12,000 H2-powered cars on the road in California. And H2 fueling stations are hard to come by. There are only two in Sacramento (where the reporter lives), 62 in the entire state, including 22 in LA, 12 in Orange County, one in San Diego County, ten in Santa Clara County and three in San Francisco. The article says that not only are H2 stations hard to find but in the Sacramento area the fueling stations have been down almost as much as they have been up, according to John White, a longtime environmental activist who drives a Toyota H2 car. "That is not a good situation." he says.

Here is something that I didn't know: The article says that another problem with H2 is the "exorbitant cost of filling the tank", around the equivalent of $16 a gallon or higher. State Senator, Josh Newman, D-Fullerton, drives a H2 cars and loves it, but he says that "it's a challenge to keep it fueled."

I'm assuming this articl is spaeking to liquid hydrogen burned in a ICU (internalcombustion) cars as opposed to hydrogen cell (electric) systems. True?

[Richard230]

I'm assuming this articl is spaeking to liquid hydrogen burned in a ICU (internalcombustion) cars as opposed to hydrogen cell (electric) systems. True?

I am not sure. I suppose that both types of cars can use compressed H2.  Apparently, whatever type of H2 system the Toyota has is what works.

[AzCal Retred]

Mostly they're "Fuel Cell EV's" (Clarity, Mirai). The last time I ciphered up the equivalency H2/Gasoline for the "local" H2 station on I5 it had an amount of compressed H2 roughly equal to a 55 gallon drum of gas. That's an exceedingly pitiful & pro-forma effort. Yes indeed they did have a refueling station, you just wouldn't want to be the 3rd guy in line at the pump...

The weird thing about the H2 burning ICE motors was that the overall fuel efficiencies were fairly comparable. I thought the fuel cell would be 2x - 4x better, but no.

[NVDucati]

Caterpillar is one of the "big rig" companies investing in burning liquid hydrogen in ICE earth movers.
I read an interview with the president of the company saying that no other form of engine can do the work to do the mining needed for electric vehicles. He makes a pretty detailed case for his position.

[AzCal Retred]

It's just the energy density of the energy storage system. Too much bulk or additional weight just to carry around "energy" adversely impacts machine function. Batteries are great but liquid hydrocarbons greatly exceed their energy storage per weight & volume. Cryogenic H2 storage adds complexity & some bulk, but apparently less so than the battery equivalent. You can recharge/resupply the energy package as fast as you can fill, no need for cabling & connections capable of handling hundreds of amps. Transitioning to H2 is a threat to existing natural gas suppliers and to electrical utilities profit margins, so there is lots of lobbyist-driven foot dragging. To me a better transportation alternative is just using "recycled carbon" & H2 to build liquid synfuels so we don't have to rework the entire energy infrastructure. An "Everyone gets a Texas" plan may not be popular with the well-heeled "House of Saudi/Aramco", "House of Putin/Gazprom" or the "House of Houston" folks.

[Richard230]

I took a look at my favorite H2 station located across the street from Alice's Restaurant today. It is now looking completely dead. The pump's LCD screen is blank and the red light that used to be on at the top of one of the equipment cabinets for the past several years is now off. A lot of money down the drain on that facility. 

[AzCal Retred]

IMHO H2 is way better off in the commercial/state/county arena. HP gas fittings don't tolerate amateur hour. Liquid H2 is even more fun. EV's handling 480 volt, 300 - 500 amp "Rapid-Charge" rates are right up there too. Room temperature liquid hydrocarbon fuels are much more in the arena of the everyman.

If you want to complain about refuelling station non-usage, look at normal gasoline stations. In my lifetime I've seen stations abandoned/sold to move across the road or up the block. That's not cheap either. Gotta follow the market. The Mirai & Clarity were marketed upscale. Likely an H2 station on the corner of Affluence Street and "I Got Mine" Boulevard would have fared better.

As a rough analogy, electric light was first used in the homes of the affluent to denote status. Maybe Toyota & Honda should have hired a tank-truck to refuel these on demand.

[GlennF]

H2 was always more suited to mining/on-farm/trucking/commercial fleets rather than individual personal transport.

[AzCal Retred]

The future is sneaking up on us. Some well-to-do punter driving his Mirai or Clarity could add a couple of these to his house, along with a suitable pressure vessel & valving and power up his H2 car for his daily drive. IF these modules slave together, 2 would allow 10 KW of ongawa, 3 would get you 15 KW & 140 KWH of storage. Enough to start & run a home AC unit all day during an outage on a hot day. Comfortably off-grid for maybe US$80K in hardware...

https://newatlas.com/energy/lavo-home-hydrogen-battery-storage/
The Lavo Green Energy Storage System measures 1,680 x 1,240 x 400 mm (66 x 49 x 15.7 inches) and weighs a meaty 324 kg (714 lb), making it very unlikely to be pocketed by a thief. You connect it to your solar inverter (it has to be a hybrid one) and the mains water (through a purification unit), and sit back as it uses excess energy to electrolyze the water, releasing oxygen and storing the hydrogen in a patented metal hydride "sponge" at a pressure of 30 bar, or 435 psi.
It stores some 40 kilowatt-hours worth of energy, three times as much as Tesla's current Powerwall 2 and enough to run an average home for two days. And when that energy is needed, it uses a fuel cell to deliver energy into the home, adding a small 5-kWh lithium buffer battery for instantaneous response. There's Wi-Fi connectivity, and a phone app for monitoring and control, and businesses with higher power needs can run several in parallel to form an "intelligent virtual power plant."
At AU$34,750 (US$26,900), it costs more than what you'd pay for three Powerwalls in Australia, but not by a huge amount, and that price is set to drop to AU$29,450 (US$22,800) in the last quarter of 2022, by which point Lavo says it'll be available internationally.
How is it better than a battery? Well, Lavo says the key bits should last much longer than a battery system, up to 30 years instead of maybe 15 from a lithium battery setup. There are also no toxic chemicals to dispose of afterwards, and the company says that even though it's a bit of a beast, a single Lavo system is more compact than an equivalent amount of battery storage.

https://www.lavo.com.au/

[AzCal Retred]

@ GlennF @ #8: Here are your ICE truck motors!    At least the rest of the world isn't brain dead. Anyone with wind, tide flow or sunlight can make their own fuel. Take a hike OPEC.

https://fuelcellsworks.com/subscribers/hyundai-doosan-infracore-hdi-unveils-prototype-of-hydrogen-combustion-engine-for-mass-production-by-2025/#:~:text=By%202025%20%2D%20FuelCellsWorks-,Hyundai%20Doosan%20Infracore%20(HDI)%20Unveils%20Prototype%20of%20Hydrogen%20Combustion%20Engine,for%20Mass%20Production%20by%202025&text=HDI%20has%20designed%20a%20hydrogen,ft%20(1700Nm).
Hydrogen engines to be mass produced by Hyundai by 2025
Hyundai Doosan Infracore (HDI) Unveils Prototype of Hydrogen Combustion Engine for Mass Production by 2025. HDI has designed a hydrogen internal combustion engine and unveiled a prototype of an 11-liter internal combustion engine with an output of 402hp (300kW) and maximum torque of 1254lb. ft (1700Nm).Feb 24, 2023

https://www.hydrogenfuelnews.com/hydrogen-engines-hyundai/8557564/?awt_a=1jpsU&awt_l=9EoFC&awt_m=iUiNsqhhvu5DlsU
Hydrogen engines to be mass produced by Hyundai by 2025
HDI’s H2 ICE is an 11-litre class engine.
hydrogen news ebookThe hydrogen-powered internal combustion engine can produce a power output of 300 kW (402 HP) and a torque of 1700 NM at 2000 RPM. Fulfilling Tier 5/Stage 5/Euro7 regulation, the engine satisfies the emission requirements to be 90% decreased to the current level to meet Zero CO2 (below 1g/kwh) and Zero Impact Emission.
Low-purity hydrogen is used to power the hydrogen engines. This makes the engines not only strong, energy-dense and economical, but the most suitable engine system for mid-to-large-size vehicles and vehicles traveling long distances. Just one charge of 10 minutes allows for a distance up to 500 km (310.6 miles), meanwhile the H2 internal combustion engines are 25-30% more economical than battery packs or fuel cells when vehicle price and maintenance costs are factored in.
The new hydrogen engines will be installed in commercial vehicles.
To both accelerate commercialization and lower costs, HDI plans to leverage its current engine technology and facilities. The new hydrogen engines that will be produced will be installed on commercial vehicles, including large buses, trucks and construction equipment. HDI will unveil its prototype hydrogen-powered ICE power unit this year (2023), with plans for full-scale testing slated for 2024, and full-scale mass production planned for the following year in 2025.
“Hydrogen internal combustion engines will be used in mid-to-large-sized commercial vehicles such as trucks, buses and construction equipment and mid-to-large-sized power generators,” said Kim Joong-soo, HDI’s Head of the Engine Department. “We will put in the utmost effort to realize carbon neutrality in response to the eco-friendly market by developing green hydrogen-related technologies in line with increasingly strict carbon emission regulations.

[AzCal Retred]

Creating useful fuel from waste plastic sounds a lot better than "rediscovering the wheel" in the transport sector. Likely less corporate profit though...

Could waste plastic become a useful fuel source?
https://www.bbc.com/news/business-64703976
Plastic waste dumps, says Prof Erwin Reisner, could be the oil fields of the future.
"Effectively, plastic is another form of fossil fuel," says Prof Reisner, who is professor of energy and sustainability at the University of Cambridge. "It's rich in energy and in chemical composition, which we want to unlock."
Dilyana Mihaylova, plastics programme manager for the Ellen MacArthur Foundation, says: "Our extractive, take-make-waste economy [means] billions of dollars' worth of valuable materials are lost."
Worldwide, more than 400 million tonnes of plastic is produced every year - roughly the same weight as all of humanity. Today, around 85% ends up in landfill or is lost to the environment where it will stay for hundreds, perhaps thousands, of years.
Now the race is on to find the best way to break those chemical bonds and reclaim the Earth's precious resources locked into plastic.
Could a new solar-powered system show the way forward?
Prof Reisner and his team have developed a process that can convert not one, but two waste streams - plastic and CO2 - into two chemical products at the same time - all powered by sunlight.
The technology transforms CO2 and plastic into syngas - the key component of sustainable fuels such as hydrogen. It also produces glycolic acid, which is widely used in the cosmetics industry.
The system works by integrating catalysts, chemical compounds which accelerate a chemical reaction, into a light absorber.
"Our process works at room temperature and room pressure," he says.
"Reactions run automatically when you expose it to sunlight. You don't need anything else."
And, assures Prof Reisner, the process produces no harmful waste.
"The chemistry is clean," he says.
Other solar-powered technologies hold promise for tackling plastic pollution and CO2 conversion, but this is the first time they have been combined in a single process.
"Combining the two means we add value to the process," says Prof Reisner. "We now have four value streams - the mitigation of plastic waste, the mitigation of CO2, and the production of two valuable chemicals. We hope this will bring us close to commercialisation."
In addition, Prof Reiner says his system can handle otherwise unrecyclable plastic waste.
"Usually, plastic contaminated with food waste goes to incineration, but this plastic is really good for us. In fact, food is a good substrate - so it makes our process work better."
Researchers around the world are looking for ways to turn unwanted plastic into something useful.
When broken down, the elements of plastic can be re-made into a myriad of new products including detergents, lubricants, paints and solvents, and biodegradable compounds for use in biomedical applications.
Nature has found ways of breaking down polymers - substances made up of very large molecules - and plastic is a synthetic polymer.,
Victoria Bemmer from the University of Portsmouth is developing enzymes that can break down plastic
"There are already bacteria out there that have enzymes designed to break [polymers] down," says Dr Victoria Bemmer, senior research fellow at the University of Portsmouth.
"We can tweak these enzymes by changing the structure of them very slightly - to make them go faster, make them more firm or stable."
Using machine learning, Dr Bemmer and her team have developed variants of enzymes adapted to deconstruct all varieties of polyethylene terephthalate (PET), a type of polyester.
The enzymes break the plastic down in a similar way to chemical recycling, says Dr Bemmer but, because they are akin to enzymes found in nature, the process can be done in much more "benign conditions".
Where chemical recycling uses chemicals, the Portsmouth University team are able to use water. And the highest temperature they need is 70C, meaning energy consumption can be kept low compared to other processes.
Dr Bemmer and her team are developing their enzymes further and hope that their work will help them create a sustainable circular economy for plastic-based clothing too.
Polyester made from PET is the most widely used clothing fibre in the world.
However, recycling synthetic fabrics using enzymes is not easy. The addition of dyes and other chemical treatments make it difficult for them to be degraded in a natural process.
"Polyester is an absolute pain," says Dr Bemmer. "Plus, it's very rarely just pure polyester. You find mixed fibres as well."
The team hope their enzymes will reduce the PET in waste textiles to a soup of simple building blocks, ready to be made back into new polyesters.
"We're at a very early stage," says Dr Bemmer. "We don't know yet if the dyes and additives to these fabrics will inhibit the action of the enzymes on the polyester chain. Hopefully they won't have an impact and we can just carry on but if they do, we can develop our enzymes further."
Worldwide production of plastic continues to increase, and is expected to triple by 2060. For many, recycling remains the focus in addressing the issue, but some argue this will never be enough.
Back in Cambridge, Prof Reisner's team are taking "baby steps in the direction" of commercialisation. They plan to develop the system over the next five years to produce more complex products and hope that one day the technique could be used to develop an entirely solar-powered recycling plant.
Around 600 million tonnes of syngas is already produced every year, says Prof Reisner, but it's largely from fossil fuels.
"If we can make syngas, we can access almost all of the petrochemical industry and make it sustainable."

[Richard230]

Here is the latest H2 manufacturing news from California.

[AzCal Retred]

Fascinating how all these are "demo" stand-alone projects using proven tech from the wayback. Fascinating how NONE of these incorporate H2 as energy storage, either by blending or as pure gas down oil wells or developed salt domes. The operative message here is to extract "Free R&D" cash rediscovering the wheel and the atechnical political lawmakers just go along with it out of ignorance. The other lesson is DO NOT get in the way of profitable natgas sales (largely extracted from public lands) or lucrative wheeling fee income for the electrical utilities. Renewable energy storage inherently conflicts with these profit-center modalities, therefore it has to be ignored/sidelined. Utility-level renewable energy storage is especially harmful to the current energy provider profit model. Let's Nationalize the grid & boot the carpetbaggers to the curb. The ONLY people interested in cheap, clean energy is the air breathing & water drinking public, not the fleet of Billionaire Playboys running the Supreme Court & Congress. Expensive energy adversely impacts the public but enriches the handful of guys controlling access to it.

And this is in freaking England...not LA or Phoenix. Rooftop PV (source & load together) should be a priority, but it's not. Source & load together means the electrical infrastructure already largely exists. Utilities don't like rooftop because there is more Capital Spend 10.5% guaranteed rate of return money to be made building electrical infrastructure into raw farmland where it wasn't before. Life's GOOD when you write the rules you operate under. Nationalize/Municipalize these a-holes. The workerbees get better bennies and the same or better money, there are no CEOs getting $70M yearly paychecks, future electrical infrastructure projects are the result of actual needs, not corporate profit-maximizing wargame strategy.

Why car parks are the hottest space in solar power
https://www.bbc.com/news/business-65626371
"Where we can co-locate solar photovoltaics alongside infrastructure that would be there anyway, like a car park, it enables us to get double use out of the land surface," she says.

[GlennF]

 " and the atechnical political lawmakers just go along with it out of ignorance"

I would potentially replace ignorance with "political convenience".

[NVDucati]

Honda, Kawasaki, Yamaha, Suzuki To Investigate Hydrogen Power With Toyota’s Help

https://www.advrider.com/honda-kawasaki-yamaha-suzuki-to-investigate-hydrogen-power-with-toyotas-help/

[GlennF]

There is some possibility that after all these years Scotch Yoke engines may finally find an application running H2 and also as H2 range extenders.

https://www.asfgroupltd.com/wp-content/uploads/2023/02/Paper016SYTECHEngine09102022.pdf

https://www.youtube.com/watch?v=bwGQlf0y6zE

[AzCal Retred]

There's a reason the venerable rotating crankshaft/swinging conrod/rocking piston layout continues to dominate engine design. With some notable forays by the Wankel of course.

https://en.wikipedia.org/wiki/Scotch_yoke
The Scotch yoke is not used in most internal combustion engines because of the rapid wear of the slot in the yoke caused by sliding friction and high contact pressures[citation needed]. This is mitigated by a sliding block between the crank and the slot in the piston rod. Also, increased heat loss during combustion due to extended dwell at top dead centre offsets any constant volume combustion improvements in real engines.[4]

[GlennF]

There's a reason the venerable rotating crankshaft/swinging conrod/rocking piston layout continues to dominate engine design. With some notable forays by the Wankel of course.

https://en.wikipedia.org/wiki/Scotch_yoke
The Scotch yoke is not used in most internal combustion engines because of the rapid wear of the slot in the yoke caused by sliding friction and high contact pressures[citation needed]. This is mitigated by a sliding block between the crank and the slot in the piston rod. Also, increased heat loss during combustion due to extended dwell at top dead centre offsets any constant volume combustion improvements in real engines.[4]

Historically yep, but they have apparently done some fancy engineering to overcome that.

The other reason for pursuing this design is the engine ends up physically smaller than any competing design.

[AzCal Retred]

How about a turbo flathead design? Boost solves cylinder filling and you effectively eliminate the cylinder head. A flat-four or flat six would be a treat. Tiny valves raise RPM limits. It has enough compression to start & run without the turbo. EFI makes it all work neatly. No real need for voodoo engines. Turbos and EFI are well sorted pathways. A 2L motor the size of an old VW sans heads making 200 BHP at 10,000 RPM sound fun?

[OldTimer350]

" and the atechnical political lawmakers just go along with it out of ignorance"

I would potentially replace ignorance with "political convenience".

I would replace "political convenience" with "globalist agenda"

[AzCal Retred]

Elaborate?

[him a layin]

Elaborate?

aw come on everyone knows it's all a conspiracy to undermine american autonomy and authority and take our guns. the UN is their organ and it's all marxist-inspired.
never mind that when the aliens finally come out of their closet and reveal themselves to be tentacle-headed greys, we're gonna need a unified earth govt to confront them. all this anti-globalist sentiment is simply a manifestation of the aliens' devious plan to keep us divided and at each other's throats. so join the resistance, support the global agenda and give the greys the finger for god, country and the flag! it's everyone's patriotic duty. EARTH FIRST!

[AzCal Retred]

Urth Furst! 

Lots of "ideers, key words & tricky phrases" here to study on...such as "intraterrestrials from Hollow Earth" aka "Reptilians"
https://en.wikipedia.org/wiki/New_World_Order_(conspiracy_theory)
The New World Order (NWO) is a conspiracy theory that hypothesizes a secretly emerging totalitarian world government.
The common theme in conspiracy theories about a New World Order is that a secretive power elite with a globalist agenda is conspiring to eventually rule the world through an authoritarian one-world government—which will replace sovereign nation-states—and an all-encompassing propaganda whose ideology hails the establishment of the New World Order as the culmination of history's progress. Many influential historical and contemporary figures have therefore been alleged to be part of a cabal that operates through many front organizations to orchestrate significant political and financial events, ranging from causing systemic crises to pushing through controversial policies, at both national and international levels, as steps in an ongoing plot to achieve world domination.
Before the early 1990s, New World Order conspiracism was limited to two American countercultures, primarily the militantly anti-government right, and secondarily the part of fundamentalist Christianity concerned with the end-time emergence of the Antichrist.[8] Academics who study conspiracy theories and religious extremism, such as Michael Barkun and Chip Berlet, observed that right-wing populist conspiracy theories about a New World Order not only had been embraced by many seekers of stigmatized knowledge but also had seeped into popular culture, thereby inaugurating a period during the late 20th and early 21st centuries in the United States where people have been actively preparing for apocalyptic millenarian scenarios.[4][6] These political scientists wrote in the first decade of the 21st century about their concern that mass hysteria over New World Order conspiracy theories could eventually have devastating effects on American political life, ranging from escalating lone-wolf terrorism to the rise to power of authoritarian ultranationalist demagogues.

https://en.wikipedia.org/wiki/Globalism
The term is now frequently used as a pejorative by far-right movements and conspiracy theorists.[3] False usage in this way has also been associated with antisemitism, as antisemites frequently appropriate globalist to refer to Jews

[Racer57]

H2 was always more suited to mining/on-farm/trucking/commercial fleets rather than individual personal transport.

Everything you mentioned often runs 24/7, so H2 is not practical for equipment that needs refueled at 3am or in western US where there's hundreds of miles between truck stops requiring every stop to have facilities to refuel.

[AzCal Retred]

Industrial equipment supply stations are built to supply the needs of the industrial equipment supplied. The usage is known beforehand, the process provides known salaries and tax revenues and so is actually important, the stations are operated by at least semi-trained personnel, it's a whole different animal than the "private car" installations. The whole point of H2 vehicles is to be able to travel hundreds of miles between fill ups, so that part of the calculation is a given. The 24/7 aspect is also an integral part of the calculation. Anyone involved in a process industry already knows all this, now you do too.

[GlennF]

Just cover the country with overhead gantries and supply catenary power.

[AzCal Retred]

Naw - yah just needs the One...put it next to the KOMA Oklahoma City installation.

[AzCal Retred]

Here's a compact antenna that'll fit on the 2026 Suzuki Electro-Hayabusa with the room temp superconductor drive motor. It may require wearing a doped Kevlar Faraday Suit when the General Atomics Equatorial Orbital Power Platform starts beaming your power subscription down. Could be tough on the pillion too.

A New Fractal Multiband Antenna for Wireless Power Transmission Applications
https://www.hindawi.com/journals/apec/2018/2084747/

[Leofric]

Re reply 23 - Putin is saying neo colonialism is finished .I don't know what that is supposed to mean but I assume it is something to do with his idea of a new world order.

[him a layin]

Re reply 23 - Putin is saying neo colonialism is finished .I don't know what that is supposed to mean but I assume it is something to do with his idea of a new world order.

i'm having a hard time caring about what putin says lately.

[GlennF]

i'm having a hard time caring about what putin says lately.

Unfortunately ignoring the crazies because they are crazy does not historically lead to optimal outcomes.

[AzCal Retred]

The crazies have siloed up. Maybe they don't want to leak top secret MAGA sedition plan info. Maybe they are having an attack of conscience. Just kidding...

[NVDucati]

The company’s CEO has stated that the automaker is thinking that it “might exit batteries.”

Rolls-Royce is thinking about stepping away from typical battery electric vehicles in favor of hydrogen cars once H2 technology has improved enough for mainstream use at scale.

https://www.hydrogenfuelnews.com/hydrogen-cars-rolls-royce/8559239/?awt_a=1jpsU&awt_l=JfUOR&awt_m=gkO3CaIL.u5DlsU

_ My personal opinion is that Hydrogen Cell technology, as opposed to H-Internal Combustion, will be the path and we won't have to junk any already existing E cars.

[AzCal Retred]

Fuel cells are about 60% efficient, and I was surprised to find that Otto Cycle ICE engines can be 50%-60% under the exactly right conditions. However, EV's can recover braking energy via regenerative braking, a trick it would be difficult to teach an ICE motor. A fuel cell Prius hybrid would be a slick rig.

And there's always the synthetic gasoline made from "recycled" carbon for the folks that can't give up "Ol' Betsy". The airline folks (synthetic JP4) will likely go that route as there's no polite or light way to store liquid H2 or high pressure (10,000 PSI? ) H2 on a 600 MPH aircraft. Liquid hydrocarbon fuels have amazing energy densities and are relatively user friendly.

[Victor]

 An electric motor at start-up that deliveries only torque and doesn't spin yet has an efficiency of zero. You want to increase systemic efficiency Invent an motor that runs relatively clean directly on crude oil, that way sleepy Joe gets more time to sleep on the pillow with the red button underneath.

50-60% efficiency for an Otto cycle engine? Reference please, where does the figure come from? Greta's fantasy land? Or do you mean Diesel cycle?

[AzCal Retred]

Looks like 49% is the theoretical max for spark ignition motors. In any event it was a lot higher than the 20%-25% I've normally seen. Toyota's Atkinson cycle Prius engine is about 40%, The turbocharged Miller cycle engines are supposedly about 15% beyond that, so about 45%, on par with many diesels. So not 50%-60% like I stated, more like 40%-50%.
The main point I was trying to make was that fuel cells aren't necessarily all that more efficient than a good Miller or Atkinson ICE engine. I originally assumed that fuel cells were in the 80%-90% conversion efficiency range, I was surprised they were close to ICE values. If you heat recover fuel cells efficiencies can hit 85%, but that's probably a job for a stationary installation, or maybe a ship or train power supply.

https://en.wikipedia.org/wiki/Engine_efficiency#:~:text=The%20internal%20combustion%20engine%20efficiency,engines%20run%20around%2093C%2C%20200F.
The most efficient cycle is the Atkinson Cycle, but most gasoline engine makers use the Otto Cycle for higher power and torque. Some engine design, such as Mazda's Skyactiv-G and some hybrid engines designed by Toyota utilize the Atkinson and Otto cycles together with an electric motor/generator and a traction storage battery. The hybrid drivetrain can achieve effective efficiencies of close to 40%. (Toyota has measured 41%)
Diesel engines
Engines using the Diesel cycle are usually more efficient, although the Diesel cycle itself is less efficient at equal compression ratios. Since diesel engines use much higher compression ratios (the heat of compression is used to ignite the slow-burning diesel fuel), that higher ratio more than compensates for air pumping losses within the engine.
Modern turbo-diesel engines use electronically controlled common-rail fuel injection to increase efficiency. With the help of geometrically variable turbo-charging system (albeit more maintenance) this also increases the engines' torque at low engine speeds (1,200–1,800 rpm). Low speed diesel engines like the MAN S80ME-C7 have achieved an overall energy conversion efficiency of 54.4%, which is the highest conversion of fuel into power by any single-cycle internal or external combustion engine.[3][4][5] Engines in large diesel trucks, buses, and newer diesel cars can achieve peak efficiencies around 45%.[6]

https://en.wikipedia.org/wiki/Fuel_cell
The energy efficiency of a fuel cell is generally between 40 and 60%;

[GlennF]

Modern aircraft tend to use engine monitors that give you feedback on every cylinder (CHT, EGT etc etc)  allowing more precise adjustment for safety and efficiency.

https://sarasotaavionics.com/media/image/9705/gi-275-eis-wgea-24.jpg?size=250

Also, because aircraft fuel injection systems are continuous flow design, not the pulsed or timed designs used in automotive engines it has also become fashionable in aviation circles to fit Gami injectors ...

https://gami.com/gamijectors/gamijectors.php

https://www.youtube.com/watch?v=rvH4xlNC6gs

[AzCal Retred]

A 200 KW fuel cell output is about equal to 260 HP or so. That would power a medium size store or several houses, so ancillary sales should be brisk. Assuming it's modular & scalable, Hyzon may be onto something. H2 in general is better suited to industrial applications and handled by trained technicians.

Hyzon’s 1st Liquid Hydrogen Electric Truck Wows in Demo

https://www.hydrogenfuelnews.com/liquid-hydrogen-truck-demo-hyzon/8560542/?awt_a=1jpsU&awt_l=9EoFC&awt_m=gQA5d.jn785DlsU

The truck traveled over 540 miles on a 16-hour continuous run.
Hyzon Motor’s commercial demo of its liquid hydrogen fuel cell electric vehicle began its run in Temple, Texas and completed deliveries to eight Performance Food Group (PFG) customers near Dallas, Texas.
The liquid H2 truck traveled more than 540 miles in summer temperatures that climbed over 100-degrees Fahrenheit. Its continuous run took about 16 hours and was further than the distance from Sacrament to San Diego, California. The successful completion of the demo showed the viability of on-board liquid H2 to fuel long-distance, zero-emissions transport.

“With increased range and no added weight in comparison to our gaseous hydrogen trucks, we believe this liquid hydrogen demo run has demonstrated potential viability for the future of liquid hydrogen in commercial trucking,” said Hyzon Motor’s CEO Parker Meeks, in a recent company news release announcing the successful truck demo.
The long-distance range of the liquid hydrogen truck puts it on par with many diesel-powered trucks.
Meeks noted that once the liquid hydrogen truck is commercialized and powered by Hyzon’s proprietary 200 kilowatt fuel cell system, it “should be able to provide long distance range between 650 and 800 miles, on par with many diesel truck range requirements.”