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terraformindustries.wordpress.com
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Short version: cheap electricity + water
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The problem is electrolysers are expensive right now. We do have cheap enough electricity, in great location solar, which is pretty common.
The tradeoff they’re talking about, where lower capital expenditures allow them to run a less efficient electrolyzer when the sun shines or the wind blows is something I expect to see a lot more of in industrial process design.
They’re assuming a monopoly on load-shifting the cheap power.
Any process with fixed costs lower than the electrolyser will just expand that stage of the supply chain and buffer the inputs and outputs.
Industrial heat is trivially stored at much higher density per volume in bricks, sand, or graphite.
Low grade heat is way easier to store in a pond.
Any variance with more than 100 cycles/yr is better served by batteries.
So you’re left with electrolysers running at 1-5% capacity factor if you want the “unwanted” electricity. Otherwise you’re paying the same as anyone else not drawing from a battery.
This means that, assuming a $100/kW electrolyser (far cheaper than exists) pulling 70kWh/kg including compression, and feeding a load at 30-90% efficiency vs. electricity you are paying $5k-30k per kW of load you feed.
Looks like a really good article, will come back to comment after reading it
Water powered car goes brrrrrrr
Actually you would never want hydrogen powered cars from an engineering perspective.
Ideally this would only be producing hydrogen for chemical processes which require a hydrogen feed stock.
You wouldn’t want the water to hydrogen plant inside the car but a hydrogen powered car would operate fine from an engineering perspective.
You forgot to read the section on hydrogen storage, infrastructure and safety problems.
But I guess you are correct that we are from an engineering perspective able to make hydrogen powered cars but I would argue that combustion is not a good solution to transportation when proper infrastructure would be able to do without those risks.
Sure if you want a range of <150km and to need a complete teardown and engineer-certified replacement of the fuelling system every 5 years for safety.
Green hydrogen has a lot of advantages for cars compared to batteries: quick refuelling, much less weight, better range. Compared to CO2 emitting fuels (including non-green hydrogen), no contest.
It’s especially good for heavy vehicles. It’s the only way we can currently use non-carbon fuels for air travel. It’s much more feasible for trucking than batteries.
Green hydrogen is more like a kind of battery than a fuel. It’s a good way to store renewable energy that cannot be used immediately, or that needs to be used off-grid. How hydrogen is transforming these tiny Scottish islands
quick refueling only matters if your travel distance exceeds your battery’s range (which for 95% of driving is less than 100 miles) I would agree on the weight issue only if you don’t engineer the hydrogen storage to properly survive car crashes. Range is of no practical use if it vastly exceeds your needs.
I find trains better for heavy transport and fixed route power lines would cover that problem in a more efficient manner.
Hydrogen would take double conversion loses if used like a battery and a flywheel would be more efficient at storing renewable energy at a grid level.
Off-grid energy storage can be done in heavy weight battery chemistries which can last forever without the maintenance cost that must occur with combustion. (heck even Nickel–iron batteries from 1901 would work)
I will grant you that hydrogen has many useful and wonderful applications.
Home energy storage and transportation are not one of them.
quick refueling only matters if your travel distance exceeds your battery’s range (which for 95% of driving is less than 100 miles)
This is such a non-argument. I cannot have one car for short distances and another one for road trips.
There are no electric cars that can get me to my Dad’s and back without recharging. He does at least have off-road parking but he doesn’t have a safe charging point. I don’t have off-road parking so charging at home is not possible. Yes, I can pay over the odds to charge while I do my supermarket shop, but I wouldn’t usually use my car for the supermarket shop and I don’t want to use my car for the supermarket shop. The only option for long journeys is to take an annoyingly long break.
Hydrogen is very inefficient, for sure. But there’s no other way to get an electric plane that can replace existing passenger aircraft. Batteries are a non-starter for heavy transport because they’re too big and too heavy to be practical. That’s why we’ve been rolling out hydrogen buses for a couple of years now.
completely fair perspective, if you are required to travel large distances outside of cities then liquid fuels would be the superior option.
But if cities are linked by high speed rail and effective bus coverage; there would be no need for a car to visit someone. #fuckcars
I do agree that batteries are not a good solution for planes but I believe plane use should be only for special cases that are extremely time sensitive (like organ transplant transportation) and are of high social benefit (which could justify carbon fuel usage)
One doesn’t need batteries or combustion in heavy transport as fixed lines can just use electric wires which saves on moving weight and would make such transport more efficient that any carried fuel source.
I go to my Dad’s by train as often as possible but prices have doubled since the pandemic and there are usually two of us. It’s become impossibly expensive, which is why we bought a car last year after ten years without one. It does not get used for short journeys because the bus and the tram still work well enough, as do our feet and our bikes.
We cannot electrify our bus routes, unless we make them entirely useless for most people. Come on. I live where I do because it’s close to the tram station. But most people need a bus to get them to a tram station. And I usually need one when I get off the tram.
And I agree that a lot of plane travel is entirely unnecessary. But I’m not about to tell people that they can’t move to another country without waving goodbye forever to everyone they left back home. It’s an obscene proposition.
We have got to have solutions that actually work. Green hydrogen ticks a lot of vital boxes. We just need to be very clear that the only acceptable hydrogen is Green. I know a lot of the hatred for it comes from Big Carbon trying to hijack it. But the baby should not be thrown out with the bathwater,
You are right in regards to very rural bus routes not being viable for electric buses but inside suburbs, cities and rural regions where the electric grid is already connected and in place, it is very cost effective to convert to pure electric.
But for rural bus routes away from a connected electrical grid, hydrogen is not a solution either as it is only 30% efficient (assuming only ideal conditions) and would be better served by liquid hydrocarbons. (I see no reason to deprive developing communities from the most efficient options)
I am in no way suggesting one would need to leave their family but one needs to understand up until the invention of the airplane, such relocation had to mean saying good bye and corresponding via mail or very rare train rides to visit with the whole family.
Green hydrogen outside of chemical processes (where it is actually useful) is a myth designed to keep the automotive industry alive past its expiration date.
The function of green hydrogen as an energy storage medium is better serviced by more custom chemistries as we are taking external energy to produce it (literally it would be the same as us taking CO2 + H2O + energy to produce gasoline [which we could do at the cost of $3.75/gal (if one ignores the CO2 collection costs)] using the Fischer-Tropsch process)
So skip the dream and accept the reality that if we are needing stored energy for transportation, it is more efficient to store it as liquid hydrocarbons. But if we need to store for transient demands, batteries and flywheels are better solutions.
Where is the supposed 12 hour non-stop bus route that can’t be served by a current-gen battery bus?
Also how is $3-5million per 100km for filling stations supposed to be trivial, but overhead wire on 5km per 100km route is impossible?
You’re trying to argue that 10-15 minutes of reliable delay on a road trip over 500km trumps hours over the rest of the year filling (and also a probably 20 minutes of delay because hydrogen filling stations slow way down and only give half a tank during heavy use).
FCEVs are a scam. The mirai is heavier than BEVs with similar range, bulkier, and has a much smaller internal volume. BEV busses are volume limited not weight limited and are already capable of covering most routes with only overnight charging (so hydrogen is worse there). Fuelling time in real world situations favours the vehicle that is sitting at 80-100% full every morning over the one you have to visit a fuelling station for. Heavy trucking is cost limited, not time limited – so filling the trucj with the cheap electricity directly at 4x efficiency is better even in the low production season.
It’s also not “the only way” for air travel because there are no planes that use it, volume constraints limit use cases to those that mostly overlap with batteries (and don’t replace liquid fuels) and battery aircraft are much closer to production (albeit limited in niche so far).
Every single use case of hydrogen has better alternatives.
It’s very hard to work out how much you know and how much you are making up.
World’s first hydrogen-powered commercial aircraft takes to the skies above Bedfordshire
Fuelling time in real world situations favours the vehicle that is sitting at 80-100% full every morning over the one you have to visit a fuelling station for.
Not unless the batteries have enough capacity to last all day. And hydrogen refuelling stations are being built at bus depots because obviously they are. Do you imagine carbon-fuel busses head to their local filling station when they run low?
https://en.m.wikipedia.org/wiki/ZeroAvia
They tested a small aircraft for a few minutes at a time (using batteries for flight times that are low for batteries) before crashing it and it’s nowhere near production. Compared to 2 seater electric planes in production for years, or actually serious passenger planes, ZeroAvia is a joke.
There are less clownish hydrogen plane projects, but they are flight testing redundant hardware with full ICE main systems.
Not unless the batteries have enough capacity to last all day. And hydrogen refuelling stations are being built at bus depots because obviously they are. Do you imagine carbon-fuel busses head to their local filling station when they run low?
Then you’re adding a redundant $5-10million high capacity filling station to the depot cost on top of the other costs. Also you need more depots because hydrogen busses (at least the ones that don’t get at least half their energy from a battery) have lower range than the top end battery busses.
As I said before. Op charging and pantographs are being abandoned already because overnight charging is more than sufficient. 0.7-1kWh per km is perfectly doable and 500kWh batteries even without current gen LMFP (which reduces weight by 30% vs lfp in use now) has no impact on payload, any route that isn’t non-stop can run all day with just a single charge during lunch breK. 1000kWh raises the floor or reduces clearance (but still less than hydrogen) and the bus will run for longer than a driver can legally.
Realistically most batteries are in the 250-350kWh range because more is unnecessary.
The only people still pushing hydrogen busses are platinum miners or oil and gas shills.
Heavy trucking is less absurd, but they can already drive for the maximum 11 hours in a 13 hour shift so there is little benefit.
