Liquid hydrogen or ammonia are both very much feasible and carbon-free.
Both Yanmar and Kawasaki are developing large marine four-stroke piston engines for hydrogen, with 2025 as launch date.
Ammonia-fuelled piston engines are easy, their only problem is idling due to the poor combustion properties of ammonia, which you can solve in the pragmatic way by using a little hydrocarbons during idle - combined with power from shore during docking, that still gets you >95% emission reductions.
Hydrogen has the problem with thick-walled heavy fuel tanks - problematic for both cars and planes.
Ammonia to my knowledge has a problem of both potential toxicity (both if gas escapes in refuelling and NOx emissions after burning) and needing enriched pure oxygen rather than running with atmospheric air.
Propane or other hydrocarbons look superior to both of these to me.
Hydrogen has problems, but at the end of the day it's viable and are the best option for planes/ships if we don't find anything better. On ships fairly easily, on planes with a fair bit of re-engineering. Local pollution aside, renewable hydrocarbons would be a better option, if they're viable at all.
If the efficiency of propane production (from atmospheric CO2) can be made even close to that for hydrogen from hydrolysis, then the systems benefits of propane over compressed and/or liquid hydrogen will blow liquid hydrogen out of the water. Hydrogen is an awful fuel. It's only real advantage is the potential for being carbon neutral, and the fact that it doesn't create noxious air pollution when used in a fuel cell. It's claimed advantage of energy density is at best a wash in most applications - higher density by mass, but much lower by volume. But everything to do with hydrogen as a fuel system is hard, complicated, and expensive, compared to the alternatives.
What's your point? I literally said "renewable hydrocarbons will be a better alternative".
I'm saying that hydrogen is a bad option, but if e.g. this renewable propane turns out to cost $1000/litre then hydrogen wins by default. It wouldn't be that surprising, current synthfuel is expensive AF. And this new headline hasn't been commercialized yet, so it might not be viable after all.
The benefit of hydrogen fuel is that, while it works poorly, it does work and is already in use today, in e.g. forklifts. It was in use decades ago, in fact. It's boring and low-risk, if we can't find anything good.
Storing propane is much easier than storing hydrogen. It liquifes at reasonable pressure so it can be stored as a liquid in uninsulated, relatively lightweight tanks (the tank under your BBQ grill is an example).
Hydrogen leaks out of almost everything, embrittles steel, is hard to store as a liquid and needs very high pressures to store a meaningful amount as a gas.
Green hydrogen is still horrifically expensive, wind powered cargo ships are currently more valuable though not actually viable without a massive carbon tax. Batteries can provide enough power for ships electrical systems. There’s some niche fully battery powered boats which work fine for trips up to a few hundred miles.
A full EV transition would also free up quite a lot of biofuels. Not enough on its own, but still significant.
Green hydrogen is expensive, yes, but less expensive than synthfuel. I'm not thrilled at the prospect of a green hydrogen future, but it's our best option for replacing fossil fuels currently, and so is what we should adopt if we can't come up with a better solution in the next 10-20 years.
To my knowledge wind-powered cargo ships can only supplement cargo ships and can't fully substitute for a proper fuel source, but I would absolutely love to be proven wrong.
The bulk of biofuels are a dead end (although some types of biofuels are valuable in recycling waste products), because modern agriculture basically just turns oil into food; BEV tractors basically don't work due to the range and charging-times needed on an already very heavy vehicle.
BEV tractors work fine with hot swapping batteries. It’s not perfect in every single way, but there are significant benefits to offset the downsides. EX: “Monarch also offers a battery swap cart to keep the tractor running and uses 90% fewer moving parts than a comparable diesel unit. ”
https://www.agweb.com/news/machinery/new-machinery/future-el...
I don’t think green hydrogen or synthetic fuel is a realistic option yet. As to a fully wind powered boats, the last fully wind powered cargo boat used commercially lasted until the 1960’s it lost but not by some huge margin. So yes fossil fuels win, but they don’t win by such a huge margin that a fuel costing 4x as much also wins.
Hybrid battery/solar + wind boats are still a common thing for houseboats and pleasure craft in part because of the cost advantages. At even a 2x cost bump over bunker fuel I suspect bulk shipping would start to go a similar route. Militaries and billionaire super yachts might go with hydrogen or synthetic fuel’s it just a question of how quickly their prices fall.
I don't think you fully grasp the sheer inability of batteries to power a cargo ship. It is something like 50x too low energy density to work. Even with wind power, it is still far from being able to pull this off. Not to mention cost: The batteries will be many times more expensive than the ship itself. The whole idea is totally DOA.
It is going to be some kind of chemical fuel, it is just a question of what and when. The alternative is just people not doing their physics homework and being totally wrong.
The batteries power electronics for navigation, communications, and ship’s systems like moving the tiller. That’s a tiny fraction of the energy needed for large cargo ship propulsion.
Wind is what provides power and scales incredibly far, we already have individual floating 16MW wind turbines. The very largest ships are approaching 60MW, but rarely operate at full power instead “slow steaming” to conserve fuel. https://en.wikipedia.org/wiki/Slow_steaming
The cost of the ship alone is irrelevant if you’re trying to sell fuel at 4x the price almost nobody is going to be willing to pay when they’re not even willing to pay full price at todays fuel prices instead choosing to travel slower than sailing ships while still paying for fuel.
PS: As to battery weight, ships scale really well around weight which is why we have ships moving 200,000+ tractor trailers worth of cargo. There’s fully battery powered ships traveling hundreds of miles for local delivery to remote areas. Which actually means going from Asia to Europe or Africa with some battery swapping is viable. Higher upfront costs and extra stops, but drastically reduced fuel consumption.
You're not putting anything like a 16MW wind turbine on a cargo ship. That thing is practically larger than the ship itself. Nor do wind turbines generate 16MW continuously. This is all just handwaving the fundamental problems away.
You're going to need chemical fuels to solve this problem. You really have to get to grips with basic physics here. Global warming can't be solved by science deniers.
PS: How are you going to battery swap on a ship? Nevermind the cost of such a thing. This is just another absurd idea stacked top of an already absurd idea.
Cargo ships swap 40’ containers at ports, many of those have electrical hookups for internal cooling. So, doing the same thing with bigger batteries and thicker cables is hardly a massive feat of engineering. You don’t even need charging infrastructure in port, toss them on a trick or train and charge em wherever is cheap.
I am not suggesting a wind turbine is an ideal fit for a cargo ship just mentioning how much power we’re already extracting on floating devices that move with the ocean.
Ultra slow steaming is 40% of max power for a 46MW cargo ship that’s 24MW so we’re in the ballpark what comes next is hardcore engineering by companies who understand the industry and they say the math is really close to working at current fuel prices. It’s you who wants people to swap to ultra expensive fuels and I’m just point out that “bunker fuel” > wind but wind > ultra expensive fuels.
And how do those cargo containers get charged? Or how can they be connected together so easily? Or how much cargo space will get taken up them? Nevermind the cost of all of that.
Again, the wind turbines you are suggest are far too big for a ship. It is totally impossible. You are not going to get more than a tiny percentage of power from wind from this. At best, you are just going to have literal sails that take off some of the power demand from the engine. The ship will still have to be powered predominately by chemical fuels.
Look, you're flat out denying the physics of this problem. You cannot solve this problem with science denier. You are doing the same thing that climate change deniers are doing.
If you want a green solution they get charged from a solar or wind farm sitting near the port. Solar farms are already being built with large battery systems to better fit the demand curve, adding extra PV and batteries to the mix is a win/win for the electric grid. Edit: Nuclear power is also viable if land is in limited supply in the area, generally more expensive than solar but still way cheaper than fossil fuels.
“Flat out denying the physics of this problem” you’re arguing that sailing ships don’t work.
Maersk the largest shipbuilder in the world already got flettner rotors to provide useful levels of propulsion, ADD a kite system and you’re traveling faster than commercial shipping doing slow steaming. As I’ve said repeatedly they don’t quite work at current fuel prices, but you want to increase fuel prices.. Read up on: https://en.wikipedia.org/wiki/MS_Onego_Deusto for why kite’s didn’t take off it was all about the economics not the underlying physics.
PS: Without paying for fuel the economics changes enough we probably aren’t going to see 200,000+ TEU ships and routes would optimize for winds. But that’s not an inherent problem it’s just a tradeoff, perhaps we invest in larger port’s that just an expense not a deal killer.
> If you want a green solution they get charged from a solar or wind farm sitting near the port.
This is just you handwaving the problem away. You will need a very reliable supply of energy for this. It actual makes more sense to convert that green energy to something like hydrogen for powering ships. If done at scale, cost will be not much more than the cost of the wind and solar energy itself. Which is potentially very low. And nevermind the fact that you have nowhere near the capacity of batteries to power your ships.
> “Flat out denying the physics of this problem” you’re arguing that sailing ships don’t work.
The largest sailship ever has a displacement tonnage of around 5,000 tons. Modern cargo ships are closer to 250,000 tons. Sailships don't work at the scale you're imagining them. It is basically going back to the 19th century in terms of shipping capacity.
> Maersk the largest shipbuilder in the world already got flettner rotors to provide useful levels of propulsion, ADD a kite system and you’re traveling faster than commercial shipping doing slow steaming.
> You will need a very reliable supply of energy for this.
Solar is extremely reliable as long as you have an oversupply when all you want to to charge batteries. At sub 2c/kWh it’s highly variable but build in 50% extra and you’re only at 3c/kWh and now very consistent across a full week. Obviously, there’s varying tradeoffs so if the cheapest solution is to stick them on a boat and charge em in another country that’s what would end up happening. There’s also obviously tradeoffs between moving shipping containers vs moving electricity but again that’s an optimization problem not some inherent limitation.
Skysail isn’t viable at current fuel prices, the technology works just fine. Current sail designs are of limited value along current routes, but those routes are also optimized for fossil fuels.
Club Med 2 built on 1992 was 15,000 tons and a quite traditional design for aesthetics, again Skysail can significantly boost propulsion. Thousands of economically viable modern cargo ships are 50,000 ton panamax ships and plenty are well below that, those 250,000 ton monsters are an economic optimization between a handful of major ports not some inherent requirement.
The total crew size is largely independent of cargo size, but even relatively small ships are moving 100’s of TEU per worker. At that point it’s only a question of what’s the most efficient design economically not what’s the largest ship.
Uh no. You are looking at a 20% load factor with solar, plus massive seasonal variations. It is completely non-doable with batteries.
Seriously, you seem like someone who is obsessed with doing it with batteries, not a person even remotely interested in finding a working solution.
Meanwhile, the alternative, just making hydrogen with the same renewable energy source and powering your ships with it, is sitting right there as an obvious answer. If you already admit to the existence of $0.02/kWh electricity, then the rest of the cost equation is also going to be low here. You've already solved the economics of the issue. The rest is scaling up, and this time there is no need for sails or downsizing ships.
Do you forget what we were trying to do? The explicit goal is charging batteries in 40’ containers and clearly PV isn’t working at night so what matters is consistency during the daytime. A flat panel on a rotating circle has a maximum theoretical capacity of diameter/circumference = 1/pi or 31.847…% on earth it’s more complicated due to axial tilt etc, but what matters is how consistent the output per day not the number of minutes per day we’re getting power.
Real world capacity factor Capacity factor 27.9% (average 2017-2019) https://en.wikipedia.org/wiki/Copper_Mountain_Solar_Facility that’s surprisingly close to the theoretical maximum for the location and design. Some break 30% but again it’s not about maximizing output just how much it cost to guarantee we can fill X TEU worth of shipping containers per ~week. Thus it don’t matter if there a 18 hour period one day when they aren’t being charged as long as you can charge enough on average.
> Meanwhile, the alternative, just making hydrogen
Sure let’s pay vastly more per gallon that’s an easy selling point. Hydrogen has maximum limits imposed by physics that severely limit end to end efficiency. It’s a dangerous bitch to store, transport etc. Low density, damages metals it comes in contact with etc, even rocketry got away from the stuff even though it has significant advantages for them.
Nobody is using the stuff because it’s got huge problems.
Have you forgotten what your goal is? It is to get ships to zero emissions. Not force a physically nonsensical idea onto the shipping world.
You've already admitted that solar is just $0.02/kWh. You can do the rest of the math and realize that hydrogen will also be very cheap. You're entirely thinking in cliches now. It is "battery = cheap, hydrogen = expensive" despite your own argument contradicting that claim.
In reality, people will just some kind of chemical fuels. If not hydrogen directly, then something derived from it like ammonia or synfuels. It is already happening in fact, and your obsession simply won't happen.
I call green hydrogen expensive because that’s what it actually costs today. There’s a reason we only get 4% of hydrogen from electrolysis, it costs more than using fossil fuels.
Look at hydrogen fuel station pricing sometimes even using fossil fuels and compare costs vs bunker fuel. There’s projections it could possibly get close to US gas prices in 20 years, but that includes road taxes, high refining costs, transportation, etc and are therefore much higher than bunker fuel actually used by boats. So the optimistic projections are doubling a ship’s fuel costs and current prices are much higher than that.
As to your “nonsensical idea” complaint, companies actually saving companies money today using it. This isn’t some hypothetical, actual ships on the ocean are using large scale batteries to save on fuel costs. Further, the absolute largest car carrier in the world is smaller than the largest sailing vessel ever built, they load and unload from the front so sticking sails on top wouldn’t be a problem. Fossil fuels are cheap, but hydrogen isn’t viable today which is why ships aren’t using it and it’s not projected to be viable for decades. Anyone who tried using hydrogen would simply be eaten alive by the competition.
You could've said the same thing about anything before it hits mass production. Wind and solar were expensive too at one point. It is not much of an argument.
The thing about hydrogen is that is made from an extremely plentiful resource: water + green energy. That puts the cost floor at below that of bunker fuel. In fact, the cost floor is pretty close to zero. So you are basically repeating the generic "renewable resources can never be cheap" argument. But it has been discredited.
Nobody uses anything like a battery powered ship for long distance travel. You are making up imaginary scenarios.
Clean energy isn’t free nor is the actual infrastructure required. Round trip efficiency for hydrogen is currently ~18% excluding horrifically expensive fuel cells which are completely off the table for these ships. On top of this you got to pay for the infrastructure to actually make the hydrogen + infrastructure to store the stuff + the increased costs of building ships to handle it.
Even optimistic estimates put Hydrogen well above bunker fuel.
> Nobody is using anything like a battery powered ship for long distance travel.
Cargo ships with hot swapping batteries are already in use. At that point it’s Europe to Asia is an infrastructure problem not a research problem. People hope to eventually solve Hydrogen’s issues with production and storage but have made minimal progress over the last 20 years. Just because we want technology to work doesn’t mean it’s actually possible to build it.
Hell just look at how much people have hyped up Nuclear as a source of cheap electricity as long as we invest in more R&D. Except even with huge investments in new designs etc there’s been zero actual progress in lowering costs.
Clean energy is regularly free or even negatively priced. It is at the very least, extremely cheap. It's funny how PV panels at 20% efficiency never stopped it from catching on. Making the same accusation against hydrogen is just repeating this already debunked argument.
The whole infrastructure for hydrogen will just repurpose or modify natural gas infrastructure. It is not expensive. It will be vastly cheaper than trying to do it entirely with batteries. And without any resource constraints, it is guaranteed to eventually be cheaper than bunker fuel. Again, you are repeating anti-wind and anti-solar argument the past. If those technologies plunged to nearly nothing in cost, why would the next renewable technology that relies on an extremely plentiful substance be any different?
Finally, you're entering into the "I'm just making this shit up" phase of your argument. People have already made ships to run on hydrogen. Something similar has happened with a variety of other green fuels like methanol, ammonia, etc. None of this is even that challenging of a problem. The only thing that is proving to be hard is trying to power everything with a battery. It is totally nuts for ships, and that's even before realizing how much it costs.
FYI, nuclear has been killed off due to legislation, many due to fears over radioactive waste. But hydrogen and other chemical fuels have no such concerns. It will scale the same as wind and solar did.
> People have already made ships to run on hydrogen.
Only at a significant loss. You can go out and buy a hydrogen powered car today and pay more for the car, have worse range, pay more for energy to move that car, and have to deal with limited infrastructure. People are operating battery powered boats at a profit, that’s a monumental difference.
Limiting yourself to “free” for electricity means spending more money on equipment. Actually making industrial scale hydrogen requires expensive electrolysis equipment and having that sit idle 95% of the time is expensive independent of electricity costs. Similarly aiming for seasonal storage requires investment in storage so it’s there when you want it. This isn’t free and no you can’t just reuse natural gas systems, even just detecting small leaks requires different equipment, the demand is higher, hydrogen embrittlement is a serious problem, and the energy density is different.
You can consistently get ~3c/kWh for close to 8 hours a day via building your solar farm, but that means your electrolysis equipment is still idle 66% of the time and your still paying 3c/0.18 = 16.7c/kWh just for electricity ignoring other costs to get 1kWh of useful energy at the end.
This is why Hydrogen is currently expensive, until something fundamentally changes with the underlying economics due to new technology it’s going to stay expensive.
Nuclear has both economic and risk issue. Legislation impacted individual countries but a handful are built each year. It’s not even just disasters, several nuclear projects have gone wildly over budget scaring both small countries and free market investors. The risks are high even ignoring accidents and the rewards don’t match those risks.
That said, I acknowledge politics has played a role it’s simply not the most important one. Japan was happy with nuclear until an unexpected 500 dollar bill, other countries look at that and get concerned.
By the time any of this hits a reasonable scale we'll be past a reasonable CO2 level in the atmosphere. The best thing to do may well be to use it as plastic feedstock and just chuck it into landfill.
Both Yanmar and Kawasaki are developing large marine four-stroke piston engines for hydrogen, with 2025 as launch date.
Ammonia-fuelled piston engines are easy, their only problem is idling due to the poor combustion properties of ammonia, which you can solve in the pragmatic way by using a little hydrocarbons during idle - combined with power from shore during docking, that still gets you >95% emission reductions.