Electric and Hydrogen trucks today struggle because a truck needs a huge amount of energy to go somewhere.
If that energy could be reduced, the problem would be far easier.
Here is a free idea for anyone working on this problem:
Make it more aerodynamic. EU trucks today have flat fronts and flat back. They're super aero-inefficient. US is better but not much. The flat front and back are primarily to meet maximum length regulations, which are to allow them to navigate small streets. Bypass all this by having an inflatable front and back that auto-inflate to make a pointed front and back when going over 40 mph on a straight road. Use the same kind of construction as a SUP-paddleboard - ie. 15 psi air and thousands of cords for shape. When the truck slows down, have the whole lot deflate to leave a flat front/back.
This will ~halve energy requirements for long distance trucking, which, considering fuel/energy is ~30% of the cost of shipping goods, is a massive financial win, as well as being good for the environment!
The main barriers will be regulatory. You'll have to persuade lots of government agencies to let you run trials of such things on the road. Trucks have pretty strict regulations, and you can bet 'stick a massive inflatable on the front' is going to mean you can't meet some of them, so will need exceptions to those regulations. That in turn will mean your truck can only drive in some states or regions, which will reduce its utility.
> Electric and Hydrogen trucks today struggle because
...pollution and carbon emissions haven't been priced correctly for decades.
Now that's changing, and ICE trucks are starting to struggle, starting at the last mile, low weight, urban end of the scale, but inevitably expanding outwords.
It also explains why the 50% savings you mention haven't already been taken advantage of with ICE trucks. The costs of developing and deploying that technology (mostly related to a political fight with the people who sell the fuels and therefore really dislike efficiency and clean air) hasn't been worth the savings available.
The people who sell the fuels have approximately zero influence over the people who sell the trucks. Truck manufacturers try to optimize overall operating costs because that's the primary metric their customers look at. Adding active aerodynamic surfaces to trucks would cut fuel consumption slightly, but nowhere near in half (as londons_explore suggested); that's simply not plausible. And it would be another thing to break.
> Last week, a group of Republican attorneys general decided to sue the Environmental Protection Agency (EPA) over its decision to reinstate the waiver allowing California to set its own limitations on exhaust gasses and zero-emission vehicle mandates that would exceed federal standards.
What's your point? That article isn't relevant to my previous comment. Nothing is stopping truck manufacturers from increasing fuel efficiency. They're free to do so, regardless of whether or not California imposes emissions requirements that are stricter than the federal standard.
Big Oil lobbies government hard to not price in externalities (carbon tax).
Therefore diesel is cheaper than it might be under a carbon tax. Truck manufacturers optimise max length & volume, so flat front and back, rather than diesel efficiency.
> I don't think they do optimize volume, because they could certainly have larger trailers.
No they cannot, at least in Europe. The outer dimension of trucks are regulated, such that street planners know what to plan for and truckers know they can pass a street.
People think ya can pop a wind farm anywhere, but ya have to be able to drive the 100m plus single piece blades there, they don't fit on regular trucks, and doesn't always go as planned.
Exactly, the benefits are fairly marginal. Its a bit like those foldout truck tails, they do have a marginal benefit but they cause truckers enough pain that many avoid them.
Oh yeah, because batteries and solar panels contain the long term pollution they create in their price right? All of these prices have a lot of factors involved and none of them are actually related to their pollution aspect. In fact pricing things ONLY in carbon emissions as people would like to do nowadays is maliciously deceiving.
Batteries and solar panels are (broadly) affected by the same carbon fees and pollution regulations as other products.
Yes, those fees should be higher, and pollution regulations should be even stricter, but if they were, (which they should be!) it would only further speed the uptake of solar and batteries, because they are less polluting than their rival technologies.
> In fact pricing things ONLY in carbon emissions as people would like to do nowadays is maliciously deceiving.
I don't think anyone is suggesting this, though it may actually be better overall than not pricing carbon at all, so it's an interesting thought experiment.
The EU is already on this with new regulations. As of 2022 european trucks can be upto 90cm longer if the extra space is used for aero bodywork. The DAF XG+ is the 1st truck that uses a 60cm longer nose to get improved aero. It will be interesting to see what other truck manufacturers will do with these new EU rules.
The lowest hanging fruit is likely going to be adding a second trailer behind the first and increasing the horsepower while simultaneously reducing speed.
Ontario, Canada made this tradeoff a couple years back on very specific motorways. There are dedicated places for super-long road trains to lash-up, drive, pull over, and disassemble between London, Toronto, and Montreal. These combinations are only allowed to drive a max 90km/h speed which further reduces fuel use and permits easier passing by standards trucks and cars.
This is not correct. A distinction must be made between:[1]
a) Driving up to 15km/h too fast outside of a city/village for more than 5 minutes or in two cases after departure is fined with 140 EUR.
b) Exceeding the speed limit once for a short time by up to 10 km/h outside a town or village is finded with 30 EUR. (11-15km/h: 50 EUR; 16-20km/h: 140 EUR; ...)
There is a tolerance applied to the measurement of 3km/h for under 100km/h and 3% above 100km/h. That should take into account the inaccuracy of the measurement; however, it does not guarantee that you get away with driving 83km/h in the autobahn, because the measurement might be a little inaccurate to your disadvantage.
Trains require dedicated rails, and increasing traffic on rails requires modern signalling infrastructure, both which are a lot more expensive to build and take decades. At least if the UK is anything to go by.
Road trains use existing infra, aren’t as constrained in destinations, and don’t take decades to roll out.
Don’t get me wrong. More rail is a good thing. But we also need more road trains too.
Roads don't just emanate out of nowhere either. They must be built and maintained, or they become useless. I doubt building new highways really takes much less time than building new railways.
We wouldn't need to build new highways for this. We'd just be changing how we use existing ones (replacing existing road traffic with more efficient road traffic).
Which will wear down bridges and streets far faster. There have been experiments with extra long trucks in Germany, but so far they haven't resulted in extended regulations. Longer trucks have severe limits of manouverability in small cities.
It's all of this but mostly the flexibility. Rail is a centralized service with unpredictable schedules. Once a truck is full it can be shipped, but rail poses an additional bottleneck. Plus then you also need a driver on the other end anyway to pick up and deliver the trailer.
Rail should absolutely be used more frequently. It just isn't well integrated with trucking right now.
In India we have Ro-Ro (or whatever it is called now) where trucks are loaded onto trains and transported over long distance, fast and cheap. Then the roads take them last 100 km or so, in the heartlands (or wherever the destination). Best of both worlds.
We do the same thing in the US for more long haul things. Also we ship a lot of intermodal containers this way.
The big issue is speed. Individual trucks moving trailers is insanely fast. Semi's are commonly moving at 110km/h here in the states. The US is highly dependant on JIT shipping so any changes to slow this down would have huge economic impacts (which we saw with covid).
An absolutely horrible idea for safety outside of the autobahn. There are many distributive roads where over taking safely is impossible with two trailers in front of you.
I too used to have fun googling the scores of patents envisioning these ideas: https://patents.google.com/?q=inflatable+aerodynamic+truck&o... - the fun part is figuring out which energy crisis or recession they emerged from (post-1971, post-9/11, post-2008, etc.)
> Make it more aerodynamic. EU trucks today .... and flat back
Definitely go touch up your aerodynamics :) The flat back is actually not as bad as you think for speed these trucks moving at. It creates a circular vortex that makes a high pressure zone.
* Asterisks apply. Ask representative for details. Commentors on HN will comment that I over-simplified.
Aerodynamics are important but unless all the roads are flat like a railway (which, of course, is infeasible) they really only impact trucks driven at high speeds with light loads. Of course any 5 or 10% savings on fuel is very helpful, and most North American companies have used aerodynamic skirts and shapes to minimize resistance, but when you're hauling 80,000lbs the density of air in front of you is dwarfed by the rolling resistance of the load behind you.
Where I live, trucks are governed to 105km/h (approx 65 mph) and frequently companies cap them lower than that, so it's not like they are driving around at 75mph. No company could afford the fuel bill.
I'm not saying aerodynamics isn't important, but only that significant changes need to be made that smooth the transition between road and rail so that single truck/trailer combinations aren't being used for stupid trips across the continent that could easily be accomodated by rail and are only used for local deliveries.
However, making rail responsive enough to tie into the just-in-time manufacturing sector is more difficult than it should be.
Cars yes, but with diesel over $5.00+/gallon there are very few trucking companies that will allow their drivers to go over 65 mph. It's simply too expensive.
The ones you see driving around at 70+mph are usually owner-operators who don't have their trucks governed.
Anecdotally, as someone with a lot personal experience driving an RV down the road capped at 65mph, I get passed all the time by big trucks. I do see plenty that are likely governed at 65 though.
I've never seen any fold-out attachments for the front, so there's probably not much to be done there, except for the roof of the cab, which often has a built-in fin/wing/whatever to help air get over the trailer.
They are not allowed in all states/areas. So you might be someplace where they are not allowed, or close enough that there isn't a good place to stop and put them back out. I see them in use all the time, but that is a reflection of where I live.
Energy isn't the problem. A small corner(100mix100mi) of the Nevada desert, or Spain can power the entire United States/Europe. The problem is storage and transport. Hydrogen solves that.
People are so obssessed about efficiency. They're completely missing the point. You don't need to be that efficent when your source of electricity of effectively unlimited.
Ammonia, the most likely carrier you're talking about has its own set of issues. It burns rather cool so will require new engine designs to overcome this. Also the engine must run efficiently or will produce nitrous oxide gases, hence smog. Lastly, and one of the bigger risk for end users is ammonia is a highly aggressive irritant. While gasoline/diesel can be bothersome in low concentrations, ammonia will send you running and choking. I personally think it will lead to consumers being more afraid of it and lead to adoption issues.
You mean a liquid hydrogen carrier pathway like liquid ammonia. That seems possible, but requires extra plants and equipment, and obviously you still have to store H2 if you want to burn it in an engine in a vehicle.
Alternate idea (which could be enabled by tele-op trucks) - make trucks go slower. Make them stick in the right couple lanes and give them a lower speed limit.
Momentum is a massive benefit that trucks try to leverage. I fully support truck lanes though, as cars are generally the cause for losing momentum on on ramps etc.
Separating different types of traffic could be a good idea, but there's no free lunch in physics. Higher speeds require more energy, period. Heavier loads require more energy, period. Wasting momentum due to curvy roads or traffic is inefficient, but higher speeds don't somehow make up for that.
Maybe speed limits are the wrong idea - you probably do want trucks to be able to speed up above their cruising speed before going up a hill. But dedicated lanes and tele-op could set up an incentive structure that favors a lower speed without any laws.
Turns out many cars and trucks are more efficient at 65mph (120km/h) than 55mph (100km/h). There are a lot of fixed losses, and ideal engine RPM is critical for efficiency.
Heavy trucks are the exception, they are typically designed for an operating point of 65 MPH. However, there are huge losses above that speed. No reason for a heavy truck to be going 70 or 75 MPH.
In my gasoline car, max efficiency is at 29 mph, or 35 if it's dark, cold and raining (energy use of lights, fan and wipers is minimised by driving faster so you need the lights for fewer hours to go the same distance)
Really? The graphs I have seen put the optimal ICE car speed at about 30-50 mph depending on car aerodynamics. For EVs it is probably even lower as drag dominate earlier.
No thanks. Try driving on highway truck route like I-5 where there are only 2 lanes in each direction. Even when the trucks stick to the right lane that still results in long delays as everyone else tries to pass on the left. Slowing the trucks down even more will just cause further delays, road rage, and dangerous driving.
> Even when the trucks stick to the right lane that still results in long delays as everyone else tries to pass on the left.
I'm always amazed in the midwest what a difference there is between traffic in states that have (and actually enforce!) a "get out of the left lane" law vs states that don't.
I-80 across the eastern half of Iowa in particular is exhausting to drive on, because a lot of people camp in the left lane and clog up traffic. That leads to desperate and aggressive driving to get around these silly bottlenecks, which kills fuel efficiency and makes the roads more dangerous.
>I'm always amazed in the midwest what a difference there is between traffic in states that have (and actually enforce!) a "get out of the left lane" law vs states that don't.
Those laws are unAmerican: they're about people doing what's best for the common good, instead of being selfish, and that's completely contrary to American ethics and mindset. That's why Americans generally hate those "keep right except to pass" signs and ignore them.
I know you're trolling, but those keep right except to pass laws are actually more common in right-leaning states with a lot of empty space. Which kinda undermines your trolling.
Or just do it where it makes sense and don't do it on two lane roads. Doesn't have to be an all-or-nothing policy. Many roads already have lower speed limits and lane restrictions for trucks. That could easily be expanded where it makes sense.
Oh, don’t worry. We’ll add more sensors and real-time monitoring to passenger cars so we’ll becable to punish those doing road rage. We’ll also put a hard speed limit in place which will be enforced electronically by the car itself.
We will then eliminate all old cars by raising taxes on them beyound what any sane person would pay.
I think that's exactly what the likes of Nikola and Tesla are doing with their trucks.
From what I understand, battery electric trucks exist in pretty much every size and weight class right now ranging from huge dump trucks used in the mining industry, long range trucks to more medium and small size trucks. Hydrogen may have a role to play with some of these.
But the decision as to use hydrogen is more a cost consideration than it is a functional necessity. The reason there are not a whole lot on the road is that cost wise, it doesn't make that much sense to go for hydrogen. Hydrogen is expensive to source, difficult to handle, there hardly any fueling stations, you need complex systems on the truck, heavy tanks, etc. It adds up to a lot of cost and limitations for not a whole lot of benefit.
As for this particular truck, it does not look like it's particularly impressive in terms of torque, range, etc. 400km range is well below the 500 mile range that Tesla is advertising for the Tesla Semi (with a ~500kwh battery). That's 2x the range (and a bit). The normal range also has a better range with about half the battery.
What is interesting is that hydrogen fueling takes a bit of time. It's not like fueling a truck with diesel. You need to squeeze a lot of hydrogen through some heavy duty pipes at very high pressure. That takes time.
People always complain that charging batteries takes so long. Well, 20 minutes of fueling time for hydrogen is also substantial and at the lower end of the scale of what a lot of EVs can do in terms of 0 to 80% charging already. There are already chargers being designed that will charge trucks at over 1MW. So, if you have 500kwh of battery, you might get it charged in about 30-40 minutes. That's a lot of range depending at what rate you are cruise (typically nowhere near the maximum capacity of the motor).
Another interesting aspect is that these hydrogen trucks have a 72 kwh battery. That's because fuel cells are not that easy to throttle up and down. So, instead it's basically a battery electrical truck with a smallish battery and a complicated hydrogen generator. Swap it out for a diesel or petrol engine and you have a hybrid truck. Swap that out for a proper battery and you have a proper battery electric truck. Same engine, just a larger battery and lot less complexity.
The reason the battery is relatively large is because they are powering a 350kw motor with a 160kw hydrogen setup. It would not be able to operate that engine at its full power. And when you are driving up a mountain, you need a bit of a buffer since you are depleting faster than you can charge it so it needs to be able to sustain high power levels for a bit.
I have a hybrid with a little battery and a small gasoline engine like this... The 'mountain problem' is real. If I drive up a long hill when fully loaded, the electric bit runs out, and the gasoline engine is really undersized. You end up limping along on the highway at 25 mph with the engine revving like crazy and your foot on the floor.
I could imagine the trucking industry might even have different models with different ratios of battery to fuel cell to motor depending on the terrain of the places it's likely to drive.
This is why big rigs have so many gears. It lets them maintain maximum power in a wider range of situations. That way they can actually reach the level of power that gets them up to speed (and more efficient RPMs) in situations like that.
I've driven big rigs. I've driven up mountains fully loaded (80,000lbs total). MOST trucks will struggle to drive up a moderate incline at that weight.
I've been in the Smokey Mountains and crawling up a hill at under 20mph.
As a long haul driver, what is your opinion on replaceable battery packs?
Assume we had these stops every 500-400km (or miles..), and you could do 4-5 hours driving per pack, and the on-site replacement process takes like 2 minutes (excluding the detour and approach time, of course..)
Look at any ad for OTR jobs. Notice the emphasis on miles, the more the merrier. It's rare for an ad to specify less than 3k miles per week. High miles aren't only an incentive, but a requirement.
Now consider several things. Drivers are paid mostly by the mile. Federal regulations dictate 11 hours of driving time daily, with a mandatory 30 minute break after 8 hours ( or 6 not long ago). On duty hours are limited to 14. As things are now, pulling into a truckstop often takes about 30 minutes after waiting in the fuel line, fueling, etc. Weighing/scaling new loads also takes time and this is necessary often. Toward the end of a shift even with the assistance of apps, parking can take significant time to find too, especially on the east coast. If a driver follows regulations, a mid-trip stop will be made for a cursory vehicle inspection, especially of tires. Many companies govern speed between 62-65mph - and this causes myriad clusterfucks of ungoverned drivers trying to pass the governed drivers. Remember, miles are dollars, and many factors stand in the way. Driving through Atlanta, or any similar monstrosity is a regular one. Detention is another, and this is a really big one that has inspired me to quit on the spot.
I could bloviate about the all that sucks in the world of trucks, but I'm quite certain that the primary element that impells the 18 wheeled slave is money. Any thing that gets in the way of those miles is discouraging. The whole experience is discouraging for me.
Much improvement could come to the industry, but mostly in theory rather than practice. I suspect anything that makes it all even slightly worse won't be too warmly welcomed. Personally, I'd probably keep doing it if I could make a bit less and ruin myself a bit less in the process. I don't want to run 3700 miles every week, 4 weeks out and 3 days home. But when I start my day, I only stop for weigh stations, at 8 hours, and to hold my piss bottle still.
Time is money while driving. If I stop on the side of the highway to jump out and pee, I lose a GUARANTEED minimum of 15 minutes. (even if the piss-stop was under a minute) It is a bizarre phenomenon that I could never rectify, or articulate precisely HOW it happens.
When you are driving, you constantly are doing math.
Miles (or Kilometers) converted into minutes until the next turn, and also final destination. Then you try to fit that into how much time you have left in your day.
A 2 minute battery change will always take longer then 2 minutes off of your driving time. Filling up with diesel takes ~10-15 minutes. Pulling into the truck stop, grabbing more coffee or tea for your thermos, going to the bathroom, all combine make you lose 30-45 minutes. It's not the individual item times. It's the accumulation. Accelerating, decelerating, traffic, etc.
The job of Driving a truck is almost impossible to make a living at in Canada if you do it legally. Now with all trucks having an onboard electronic log-book, I'd never even try.
No, this is why big rigs make the same amount of maximum power at all points along the hill.
The reason hybrids have less power mid way up a hill is that they use the combined output of two power sources: the engine and motor(s). When hybrids deplete their battery, the only power remaining is the output from the engine. This mode of operation is unique to hybrids. The state-of-charge management software in hybrids attempt to mitigate this, but their batteries are only so big.
To be fair, most vehicle types have similar problems but they're a result of heat rather than battery exhaustion. In a pure battery EV you can run into thermal limits: drawing too much power for too long overheats the motor and batteries. Same thing happens in ICE vehicles, though I think the difference between max continuous power and max instantaneous power tends to be greater in EVs.
It always surprised me that gasoline engine manufacturers didn't cut down on the size of the radiator and cooling stuff to save money, and then say "you can only be full throttle for 1 minute at a time, and after that it will reduce to 60%". In a typical car use case, it's very very rare to be at full throttle for over a minute.
They have to have some wiggle room for high ambient air temps that happen in some places, and it’s cheaper to build one car than build a different one for each climate zone. If you go to a high performance driving event at a racetrack on a hot day, you’ll occasionally see cars that overheat.
It can happen if you're going up a long hill or towing something. Probably no car company wants their car to be known as "the car that can't make it up a hill without the radiator boiling over" even if it doesn't actually happen all that often.
>As for this particular truck, it does not look like it's particularly impressive in terms of torque, range, etc. 400km range is well below the 500 mile range that Tesla is advertising for the Tesla Semi
Ah yes, the classic comparison of a real product versus something Tesla says on a website splash page.
You need to think in miles not cycles. How many hundred thousands of miles will the battery last until it needs replacing? Most ice trucks kind of do up to about three quarters of a million miles before they head for the scrap yard. Maybe a bit more if you take good care of it. By that time they will have consumed hundreds of thousands of dollars worth of fuel and needed lots of maintenance to replace lots of its moving parts.
Batteries look pretty good when you consider that you can charge them a few thousand times before they degrade to below 80% of their original capacity. Electricity is of course not free but can be sourced a lot cheaper than diesel. The savings on that probably create a pretty nice budget for replacing the entire truck. But it might be cheaper to replace the battery and drive it for another few hundred thousand miles.
The economics of this don't favor diesel engines. That's why electrical trucks and vans are so much in demand right now with companies operating fleets of these commercially.
I was thinking about this yesterday. We should probably start allowing active aerodynamics in racing, especially electric racing like Formula E.
Active aerodynamics are under-utilized. We start to see them, but they could be used much more, as break or turn assist, etc.
Imagine a car with retractable wheels. Only have a couple (or single) "bike" (narrow) wheel(s) for propulsion at highway speed, rely on aerodynamic controls for the rest, and on lift if necessary. Deploy aerobrakes and lower both the body and wheels in case of an emergency braking.
Such a system would be much more complex, but it could probably be engineered to be as safe as current cars (with aditionnal self- checks, attention to failure modes, etc).
I am not sure how much energy could be saved, but it's probably substantial. Plus people would finally have their "flying" cars (make them jump over detected obstacles too!).
There probably are some low-hanging fruits too, like deployable wheel covers for people who do not want to sacrifice low-speed aesthetics.
Meh, no. Essentially all the aero stuff you see in racing, including active aero and fans and stuff, is to increase downforce. Which is absolutely useless, unless you're going more than 150 km/h (90 mph) while cornering hard.
Take the active spoiler on a Tesla Model X for instance - it is 100% a toy for people who enjoy the Transformers aesthetic. I don't think there are published numbers for it, but the Porsche Panamera which has a substantially more agressive spoiler is reported to produce a whopping 7 kg downforce at 250 km/h (150 mph), decreasing substantially at lower speed.
In the ordinary cars that actually need spoilers - famous example is the Audi TT - it's in order to fix crappy airflow giving lift at high speed, that is caused by the design of the car being optimized for looks rather than aero.
And aerobrakes?? Anything that's not big enough to cover 4 highway lanes is completely ineffective at speeds below 100 km/h (60 mph). It would be substantiallt more useful to install boat anchors.
For anyone unfamiliar, a fan car uses motor driven fans to actively create a low pressure zone under the car, while also reducing the low pressure drag bubble behind the car. This particular one is all electric and quite compact.
It's very fast, and yes footage of it looks weird, almost artificial, because its sustaining grip through corners that rivals F1 cars, with the torque of electric. Running full tilt the fan system creates about 2000 kg of downforce. But the neat thing is you can flip a switch and then the thing just becomes a Nissan Leaf with a really crazy body kit. So some future "track day" car based on this concept would be surprisingly practical.
I think the future of auto racing in a pure electric era is going to be surprisingly bright.
Anyhow, not really relevant to talking about making big trucks more efficient, but thought you'd find it interesting.
> But the neat thing is you can flip a switch and then the thing just becomes a Nissan Leaf with a really crazy body kit. So some future "track day" car based on this concept would be surprisingly practical.
This car is really cool, I'm not going to argue against that for a single second. But your suggestion of a "practical track day car" is missing the fact that there are two things making this crazy fast: huge downforce and ridiculously low weight. It weighs less than half of what a Nissan Leaf does, has a single seat, no storage for anything, no aircon etc. etc.
If you tried to make it approach the practicality of a Nissan Leaf while still being performant, you would not just need more space and weight for the practicality, but you'd end up tripling the weight since you would also need a much bigger battery pack to keep the runtime at the current ~30 minutes on a track, bigger motors to keep the acceleration high when you're dragging that weight, much wider tyres to enable cornering at these speeds, etc. etc. Then you're no longer killing hypercars but rather maybe matching a Bugatti Veyron, and you might as well just go for standard aero so you don't have the 120 dB (!!) fan noise inside the cabin.
Nope. There's already a variety of track cars in this weight class, including road legal ones. Check out Palatov motorsports for example. This compact but high performance format is indeed very practical and in fact in very high demand, at least for race car crap. If you can spend the same amount of money as you would on a track built 911 for something considerably higher performance, a lot of people will.
Sure you can get very lightweight two seater road legal track cars. You can even slap an Exocet kit on an MX-5 and get that for very cheap.
But you said "Nissan Leaf". A five-seater car that can fit a full baby stroller plus a bit of luggage in the trunk. That is fully incompatible with being a lightweight track car.
I'm sorry, but then I don't understand the point of the original comment. As we agree, you can already buy a lightweight two-seater track car with very good performance for quite cheap. I understood the point of your original comment to be that with active aero devices we could now have something far more practical, like a Nissan Leaf, but still having very good track performance. If that was not the point, then what is the new thing you think is going to be enabled by active aero?
There was some truly fantastical stuff imagined in the 1950s [1]. I’m particularly fond of the GM “Firebird” self-driving jet-turbine cars [2]. They prominently featured various winglets. Not sure if they were there just for futuristic looks and jet-age appeal or if they were intended for the kind of use you describe.
The concept is widespread, but to my knowledge there isn't a name for it. Bahnization is meant to be a play on carcinization, the tendency for things to evolve into crabs.
I heard they even want to electrify them and put them on rails, then they'd run electrical cables on top of the rails so they wound't need batteries. This would be hyper disruptive
Electrified freight rail has prevailed in Europe, but mostly because the European rail system is optimized for passenger travel which favors faster and shorter electric trains. America freight trains are several times longer than European freight trains, use double stacked containers (which don't fit under the wires Europe uses) and run slower. This makes them disruptive to passenger rail, but also more efficient. As a consequence of these factors, America moves a much greater percentage of its total freight tonnage by rail than Europe, which relies more on trucks.
So in short, electric freight trains are not 'disruptive'; they don't compete with diesel freight trains unless you have enough political pressure to prioritize passenger trains above diesel freight trains.
The US freight railways have priced wiring their rails. It is possible to do this, and double stacked containers are not a problem (except for a few bridges that are already borderline for being high enough). Problem is it is only worth it if you have every rail electrified, just a short section in some out of the way rarely used rail that isn't wired is enough that they have to have diesel locomotives everywhere just in case they want to send that train to the one unwired track. And so it doesn't pencil out until diesel gets substantially higher and remains there.
That is according to the railroad. There are others who question the math, which is a valid thing to do, though I don't know who is right. In any case it is possible to wire all US freight, but so far nobody has done it.
Electrified rails don't prevent diesel locomotives rolling down them, so if it was cost effective right now to electrify the most active lines, they'd do it.
And India runs electric double-stack container trains, but of course it would be an enormous upgrade project to convert to this -- tunnels and bridges more than the wires: https://www.youtube.com/watch?v=yNq8lP6cfL4
The song Convoy references this - https://www.youtube.com/watch?v=Sd5ZLJWQmss - on the US interstates trucks will kind of "naturally" form convoys and the lead truck will swap off now and then; the rest will "draft" behind it.
If you want to be as green as possible with today's technology the holy grail is probably LPG derived from nuclear reactor powered atmospheric carbon capture. Existing fueling infrastructure is used, low vehicle emissions since it's not a liquid when injected, retrofit is possible for every vehicle on the road today with existing and proven technology, compact fuel storage, familiarity in much of the world, the works. It's great.
I don't think this is true if you factor in the Total carbon from the process of actually electrifying the roads. Its a ton of cabling made out of a ton of metal that needs to be mined.
I don't think it's a clear win. Because the scale of either initiative seems to be massive it warrants further study. Regardless, electrified freeways are a very interesting concept and I have never seen them anywhere yet.
Inflatable parts will need a way to ensure they can't obscure the windshield after a catastrophic failure, e.g. hitting a deer at 70mph.
(Of course you could just over-build to withstand the impact, though it would make for an interesting liability case (and interesting dashcam video) the first time a deer gets bounced off the highway and through someone's roof)
Modern aerodynamic designs have mechanical flaps to allow in just the necessary airflow for however much cooling is required. Hot day going up a hill - the flaps open. Cold day lightly loaded going downhill - the flaps close to reduce drag.
An inflatable cone could use the same type of mechanism
Hydrogen especially has this problem because the produces a LOT more waste heat than a pure battery-electric powertrain. One person familiar with the matter once told me the cooling system (fan, coolant pump, etc) on the heat exchanger of a fuel cell hydrogen semi truck prototype used about as much power as a Nissan Leaf.
Why would it impact braking distance? Aside from "everything affects everything" of course. I can't see this majorly affecting the overall vehicle's momentum or braking ability at any given speed, and speed limits wouldn't change.
It would impact braking distance because if the air isn't slowing the truck down as much then it will take longer for the brakes to slow the truck down.
That doesn’t matter much for slowing a truck down due to the high inertia. Really good low rolling resistance tires (Super Singles) should actually reduce stopping distance as they generally have a bit more contact area. You want low amounts of slippage on the tires while driving as slippage is wasted energy, which should give you more margin when you need to slow down.
Electric trucks also have a massive advantage in mountainous terrain due to ability to dump energy into the battery instead of the brakes which can and do overheat.
Oh that's a great point. It reduces drag, which would normally help braking distance. Thanks for explaining, I was genuinely having trouble thinking of how it could affect things.
Okay buddy, how about you let your car/truck/SUV be hit by a 150,000 lbs “airbag” and I will watch from afar to see what happens. I’m thinking pinball and the lanes as bumpers, yeah?
Assuming your truck does 60 mph, it appears it does[1]. 80Hp for rolling resistance, electrical and all other losses, 120Hp for aerodynamic drag.
Of that, cars modified to be super efficient (eg. [2]) can get the Cd down to about half (from about 0.31 to 0.17). Trucks could probably achieve an even greater improvement, because production cars already have a slanted windscreen and rear trunk.
So, overall, I stand by my claim that energy use of trucking could be reduced by about half with aerodynamic techniques.
You're right because internal combustion engines are so inefficient that more than 50% of energy is wasted before it can even contribute anything. But in terms of useful energy leaving the engine it's a different question.
Once you get to long-haul speeds, the energy cost is almost entirely split between air resistance and rolling resistance, but air resistance has the edge, (about 50%), rolling (30%), drivetrain (5%), and everything else (10%).
After you've accelerated the truck to highway speed, the weight only matters due to friction. The friction and aero costs are large enough that the acceleration cost doesn't dominate.
All these assume flat terrain. As soon as you start adding hills things look completely different. That's the one reason why I think e-trucks make sense, the ease of regeneration rather than burning off the momentum as heat.
> Make it more aerodynamic. EU trucks today have flat fronts and flat back. They're super aero-inefficient
Since you obviously haven't driven on the roads these trucks need to navigate, I'll just say it: they're flat because they have to navigate lots of tight roads and turns...
Edit - obviously missed part of the comment but still, long-distance trucking is less significant in the EU. Rail networks take goods much closer to the final destination than in the US... That's why it actually makes sense, now.
Still silly considering their solution is a large amount of complexity for limited benefit. Most roads have lower speed limits (thus aerodynamic drag is not nearly as significant) and long-haul trucking isn't really a thing in the American or Aussie sense... Far more rail networks, less distances to drive.
Like, they're being rolled out now... Electric vehicles actually make sense in Europe (distances between most places are short).
The solution for electric trucking has been obvious for 50 years - overhead cables on all major highways.
It is the cheapest and most efficient solution, the trucks only need enough range for local delivery and transport, and since they charge from cables, they dont occupy petrol stations.
Because the logistics never worked, and won't work for at least another 10 years.
1. How do you use it? First you need an electric truck, or a truck where at least 50% of its wheels are connected to electric motors. Either way you'd have to retrofit existing fleets of all shapes and sizes, so one or more companies would need to specialize in doing that, which would be very expensive initially. So you have to have an electric fleet to retrofit, or retrofit an ICE fleet (which makes zero economic sense).
2. How often is it used? The truck might actually only spend 1/2-2/3 of its time connected to the system, what with time waiting to load/unload at ports and depots, time before/after you're on highway, dealing with traffic on the highway itself.
3. How do you pay for the energy? You need a company to generate the energy, a company to charge users for the energy, a way to identify the truck as it's receiving the energy, tariff management software, etc.
4. Where are you going to install it? What roads will or won't work? How long will that take before you have enough roads that you'd stop losing money? Mostly long haul, so this has limited application, even in trucking.
If all the trucks were electric, all exactly the same size/type, the system were installed on all roads, all the companies needed to service it were in operation, and you trained enough service staff, and electricity was cheap enough that the portion of your ride would be offset by the amount of time you are charging that you could carry a smaller battery, then it would make sense.
But first we need to roll this system out on all highways, then everybody needs a BEV, then we retrofit them all, then shrink all their batteries, and then it will make economic sense. Before that all happens we need enough chargers, enough grid capacity, cheaper cleaner power, and enough BEVs rolled out, which will take 10 years at least.
Electric trams work in cities because they have short routes, a small identical fleet, need very little battery, and all the money comes from one pool (the city).
> first we need to roll this system out on all highways, then everybody needs a BEV
Essentially your complaint seems to be that we don't get a free lunch, but that's never been an option
You have only 3 options: large expensive batteries on every truck, smaller batteries + overhead wires, or some kind of fuel like hydrogen. In all cases you need new vehicles, and in all cases you need new infrastructure to handle charging and/or fuel.
Production of fuel from electricity and it's distribution is always under 40% efficiency. So if you want efficiency, the only question is cost of overhead wires vs cost of larger battery in every truck.
Most of the battery would be spent travelling long distance on large, straight roads, and those are also the easiest roads to electrify.
Also what's with the complaint about energy billing? We can put a 5g connection into every car and make it charge us for heated seats, but measuring energy is a problem?
You just need electric trucks with one pair of drive wheels powered by electric motors. Maybe more if you want more traction, but an 18-wheeler doesn't need 9 drive wheels. It might have 8, if the tractor has two drive axles with dual tires. In practice you could just replace the engine with an electric motor and keep the rest of the drive train the same, as is done on many EV conversions now.
If the system is on the major roads, then that's where the major energy is being used. If you're stuck somewhere in traffic or waiting to load/unload, you're not actually using much energy.
Honestly I'd be okay with the energy being unmetered. I think the cost to society of CO2 emissions is probably greater than the cost of supplying trucks with free energy would be anyways, so I think it's probably a net win for society to have it as a free service. But there are also ways to charge for it if we wanted to go that route. Paying for the energy is a non-problem, you'd just need to decide on a policy.
Ideally in the U.S. this would be installed on interstate highways, at regular intervals. Maybe 5 miles on, 20 miles off or something like that. The overhead lines don't need to be everywhere, they just need to be in enough places that cross-country shipping is possible, and local shipping between major cities is possible.
Same reason Detroit doesn't have useful mass-transit.
Entrenched interests make more money by prolonging the problem. Arguably the solution would be economically superior (vastly so!), but the folks who'd profit from it aren't in power _now_, and government lacks both the technical competency to understand what to do, and the balls to do it.
Because historically diesel has been cheap and the externalities have been ignored. It's also a major infrastructure project, and getting it installed widely enough to be useful on, say, the interstate highway system in the U.S. would require an act of Congress, plus buy-in from vehicle manufacturers and operators, plus widely-agreed on standards.
I mean, we still haven't even electrified all the railways, and the proposal for IceLink, a cable to import cheap renewable power from IceLand to UK, was sitting on the shelf for 60 years.
Also we had trolleybusses in many cities and got rid of them
I very much agree we should be electrifying our major roads.
There's a couple ways to do this though with pros and cons. Overhead lines are cheapest, but they'd need to be high enough that they'd be impractical for passenger cars to access.
Rails embedded in the road are a technology that's being tested in Sweden[1]. It's a bit more expensive to install, but the advantages are that it can be used by both cars and trucks, and it's less visible than the overhead lines (which some people find unattractive).
A third option is wireless, which is the most expensive and the amount of power you can practically transmit is a lot less than the other two methods.
I think the rails option is probably best if we want to kill the range anxiety issue for trucking and personal vehicles at the same time, but there are good arguments for the overhead lines too.
Your link doesn't support your claims (that it has been "obvious for 50 years" or that it's the cheapest and most efficient solution). I don't doubt that it's cheaper and more efficient than large BEVs, but like the other commenters, I would like to know where this has been conclusively studied and why this hasn't been deployed at scale anywhere.
You misunderstood the context. I didn’t request a citation, I pointed out that the provided citation didn’t support the provided claims. I mentioned that I would be interested in learning more, but that’s not the same thing as insisting on a citation.
That is the weight of the hydrogen fuel. It does not include the weight of the tank nor the fuel cell so is not comparable to battery weight in a regular EV.
The trucks also have 72kWh worth of batteries in them and it is not clear if a 400km range includes a fully charged battery pack at the start.
Interestingly Hyundais page has slightly different specs for both fuel capacity as well as battery.
All hydrogen fuel cell vehicles use small batteries to buffer charge to actually drive the electric motors because the fuel cell power output isn't high enough.
73kWH isn't huge for a large truck, equivalent to current small passenger EVs.
For a vehicle whose fundamental purpose is to haul heavy freight, the excess weight imposed by batteries is uneconomical, which is a why fuel cells make sense - especially when the H2 is renewably generated.
A promising development is physical-chemical storage that doesn't require compression for storage, that seems to make hydrogen powered vehicles far more likely to win out over current battery-based EV technologies.
One of the technologies metal organic frameworks (MOF) seems to have been creating some buzz recently.
> far more likely to win out over current battery-based EV technologies
As a BEV owner, I'll tell you right now that until the H2 can be filled at my house, I'm not willingly giving back the portion of my life I used to spend at a fuel station.
At the rate batteries and charging are improving year-over-year, compared with the practically non-existent hydrogen infrastructure (how many states have -any- hydrogen fueling stations? Two?), I can't see hydrogen ever taking over. We have a grid already which delivers electricity far more extensively than any liquid fuel infrastructure ever will.
Even with zero storage costs, hydrogen cars can't compete with batteries, since it's electricity -> battery -> electric motor vs electricity -> hydrogen -> battery -> electric motor and that extra step takes energy.
It's only on longer distances that it begins to make sense as a tradeoff but even there it's not clear there's much room for it in the market.
Surely with hydrogen it's a fuel cell (and relatively v. small battery for regenerative braking and such), not a battery like a BEV? And as the hydrogen, using a tech like MOF, would be cheaper to store, and easier to store longer term ... the extra energy expense seems a priori to remove a lot of e- waste and reliance on mining in developing nations.
I'm not sure how the life-cycle overall energy usage compares, would be interested in reading a study of someone wants to link one.
I'm hoping that hydrogen storage will become easy enough that we'll use that for large scale excesses like those from nation-size grids during excess production. So we can do seasonal shifting at scale.
Hydrogen Fuel Cell is about 4x less efficient than BEV because you lose about half the initial energy making the hydrogen and half of that going back to electricity again. It's just very hard to come back from that if you have an alternative that uses the electricity directly.
They're still better than conventional ICE (as long as the hydrogen is made from renewable energy) but just on energy alone BEVs are about 88% efficient, FCEVs 22% and ICE 18% efficient.
How much of that is recoverable? With a heat engine on the compression side to reclaim the heat, and a turbine on the expansion side to reclaim the work.
Sure but in that case please add energy costs for recycling the batteries bs recycling tanks for hydrogen. And I do not see how batteries can win in this race.
Battery fanbois choose to ignore why batteries suck so much: they weigh too much, they take up a lot of space, and they take forever to recharge.
They see hydrocarbon based fuels are dirty, but you cannot really beat that energy density.
The advantage of batteries is that you can manufacture them into any form and in case of cars, you can just hide them under the floor.
Fine, works well enough in that particular use case.
Does not discredit the what I said at all. There are many other applications where the volume and weight of the battery would make it unfeasible.
You are confusing cells with batteries. A battery is a collection of cells. This difference is rarely important and so few people ever make it. In this context is matters as a EV has many small cells in the battery. You can put those cells anywhere they fit. You can't split an engine up like that. Thus while the battery itself needs more volume and weight than an engine (or at least that is the claim, depending on range desired this might or might not be true), you can put them in empty space where an engine cannot fit.
Looking over the steady increase in energy density and steady decrease in recharge time, the future of batteries still looks pretty bright. Another 20 years and we'll see parity with liquid fuels for effective energy density.
So are batteries and the energy they are charged with.
That is such a dishonest argument. Of course the intention is not to dig up hydrocarbons to then transform them into hydrogen to then later transform them back into hydrocarbons.
Even if you assume ample clean electrical energy as a given, breaking up hydrocarbons is still the easiest way to get hydrogen.
Together, solar/wind/nuclear/hydro produce about a third of all the world's electrical generation. Despite this, only 4% of hydrogen production in 2020 used electrolysis; 95% was produced from fossil fuels.
Deceptive? I'm comparing sources of hydrogen that don't produce CO2, to those that do. The supply of carbon neutral electrical power far surpasses the supply of carbon neutral hydrogen power. It's not even close.
I don't know why you're bringing Germany specifically into this (misdirection? deception?) The overwhelming majority of hydrogen production comes from fossil fuels no matter what country you look at. If you replaced all the nuclear and hydro in the world with solar power, most hydrogen production would still be coming from hydrocarbons. Germany produces about 10% of their electrical energy with solar power, so do you think they produce 10% of their hydrogen with solar powered electrolysis? Hell no they don't.
Electricity -> hydrogen sucks even if you have a 100% solar grid. "Green hydrogen" cannot compete with batteries. Hydrogen only looks kinda okay relative to batteries if you're getting the hydrogen cheap by breaking apart hydrocarbons instead of water (aka "gray hydrogen"), and even then it sucks and has gotten out competed.
That's simply not relevant. Exclude nuclear from my above comment, consider only solar and it makes no difference. Using any kind of electricity, solar or otherwise, to split water to get hydrogen is not competitive with steam reforming of hydrocarbons and it certainly isn't competitive with batteries. The most economically efficient way to get hydrogen is to get it from hydrocarbons, and even that is not competitive with batteries.
> Green hydrogen produced by the electrolysis of water is less than 0.1% of total hydrogen production.
This is not the way it's done, and it's not because we don't have enough solar panels. It's because electrolysis sucks. Hypothesize a country where 100% of the grid is run off solar if you want to, "green hydrogen" is still dead on arrival.
That’s 1.7% of the worlds population, which is definitely a solid representation of the world.
Just as an aside, there is this little known country: China, it has 47 active nuclear power plants with ~10 more under construction and 15-20 more in the planning stage. But maybe they haven’t heard about Germany and California!
> Dams are now being removed at a rate of more than one a week on both sides of the Atlantic.
> The building of dams in Europe and the US reached a peak in the 1960s and has been in decline since then, with more now being dismantled than installed.
A major reason why:
> Many large-scale hydropower projects in Europe and the US have been disastrous for the environment.
Interesting, thanks. Hadn't heard about any plans to phase out hydro here in Germany. I knew we didn't build new ones (for the reason you've stated + at some point there's not enough space left), but don't remember any discussions to remove existing ones.
It’s not dishonest at all. There is a very real path to renewable energy with solar and wind.
There is not one for hydrogen manufacture (unless you provision heaps of renewables to do it, in which case why waste time on the hydrogen step - just put the energy straight in the battery)
I'm thinking Solar is going to be our main renewable energy resource. It sucks for heating in winter and transportation. Hydrogen definitely is a great solution for these problems, just need to improve the efficiency of turning electricity into H.
IMHO, the easiest way forward that makes sense from an engineering as well as financial standpoint:
overbuild as much energy capture as possible: solar, wind, nuclear, doesn't matter as long as it is captured at a location where it is cheap and convenient to do so.
Then use power-to-gas tech and get a well behaved hydrocarbon fuel which is easy to transport anywhere in the world, stores energy at a high density in a relatively safe way, and can be used in practically all applications.
And yes the conversion is super inefficient, which is why you need the energy capture to be cheap and to have maybe 300% of needed capacity.
Thanks, this is what I was trying to say but you did it better. :) Its fascinating things like Steel Mills which require a lot of heat are probably best located in deserts.
Electricity can run heat pumps which are great for heating. Even better if its a water-to-ground loop underneath the building, if there is no existing district heating system.
Wind is the most efficient renewable, followed by geothermal, hydro, and then solar. Solar is nice in extremely sunny places but otherwise it's more of a back-up.
50% of current H2 is used for refining fossil fuels.
And, much like solar, it's not some random efficiency or capacity stat that matters, it's cost. Low cost electrolizers are the next big thing that will prompt Americans to ask "Why is China the world leader in this technology we've been ignoring or actively spreading lies about?"
Cost matters a lot more than efficiency. The two are related, but not the same. The correct question to ask is how much does a kWh of hydrogen cost, and how much lower can we get that.
Yes this is crazy, there is no point using Hydrogen right now.
Solar panels are getting so cheap so quickly that in sunny places electricity during the day will be virtually free. 50% efficiency is pretty good in that case.
Don't need to go that far, we could put giant solar panels that would soak up sunlight 24/7 and transmit that to earth. I see it work on small scale experiments, I really think that is SpaceX's ultimate game plan. Only those with capacity to deliver payloads at scale will be capable of building these energy stations.
How they would deal with objects, meteorites and repairing is another concern but I'd imagine it won't be a giant solar panel but modular ones that are floating in cluster
The hydrogen is produced by cracking H2 out of oil. The H2 is then liquified using electricity made mostly by burning carbon. The liquified H2 is then transported on diesel trucks. Don’t fall for this carbon energy fake out.
"Hyundai – which in its release did not clarify if the fuel cells would be charged with “green” hydrogen, using 100 per cent renewables – plans to utilise the launch of these new Xcient trucks as an opportunity to further expand its business into the wider European commercial vehicle market."
Yeah, newsflash, its not. Usual hydrogen trojan horse for continued fossil fuel use.
Aaaand, with Russia turning off the spigot for natgas...
There is a long list of reasons why hydrogen might fail as a truly clean fuel, but it makes sense to get real world use cases in place. 20 years ago it was far from certain that solar power could ever be practical for diverse applications.
Still, I would estimate it will take 20 years to learn if we will be casually storing wind power in the form of hydrogen for random consumer use cases the way we now use solar panels.
We might also casually transfer it around the world in very low loss UHVDC transmission lines.
As well as storing it short term in water reservoirs (or other gravitational storage), massive battery banks and in a bit longer term (like between seasons) as heat.
Not saying that hydrogen can't have a role, but due to a low roundtrip efficiency it might just have a niche.
I’m a big train geek and I hate trucks but I also know that we don’t have time to wait for a transport revolution if we want to prevent the climate emergency.
Assuming you are getting the CO2 from capture and the methane from synthesis.
Meaning you would have to make sure all companies from all the countries in the world won't try to make money by using a cheaper and easier to access source of methane once there is a huge market for it.
The USA are not the world. Even if suddenly they managed to taxe all the carbon in their economy, and all imports coming into their countries, you cannot force the world to follow.
China, Russia and India exchange massively between them, with Europe, Africa, and internally. Those product would be cheaper, since no carbon tax, so no incentive.
It's a hard problem to solve.
If we get a big hydrogen market, the problem never needs to be solved.
Banking on all politicians in the USA and Europe to vote and maintain forever a carbon import tax is a big bet.
And it won't affect exchanges of goods between Asia, Russia, South America and Africa, or internally in each country lika China or India. Internally use goods will not be taxed, and be cheap, so they will import less, use more internal good, and pollute more.
It's like saying don't build solar panels because we use petrol for them.
It's a chicken an egg problem.
We are using methane to produce h2 because synthesizing fuel (any fuel) is incredibly energetically inefficient. Otherwise we would be using electrolysis for h2.
Either you decide it's a problem, and you don't synthesize any fuel, or you will, and you'll oversize the energy grid and improve the synthesis process efficiency.
This thread assumes we decided we should synthesize fuel (I'm not sold, but I'm debating in that context).
If we do, then synthesis will never beat sourcing in efficiency for methane, since it's a direct process. But if there is a huge market for h2, there will be a incentive for over-sizing the grid and improving on electrolysis to the point that it can be competitive against sourcing methane + synthesize from that, which are 2 steps instead of one.
However, there is no way we can find a way to compete against sourcing methane (and no more step) alone. No good incentive to create.
Synthesizing h2 from methane is also done by electrolysis, it's just cheaper to electrolyze methane than water. This is fundamental - it takes less energy to release hydrogen from methane than from water, to such a degree that even though water is free it's still not economical. If you are concerned about people using fossil instead of synthetic methane to cut costs, you should be concerned about people using methane instead of water to cut costs. Either you can get people to comply with regulations or you can't.
Fair point. I guess I underestimate how cheap sourcing methane is if it as no change of offsetting the difference in electrolysis efficiency in the future.
What’s the environmental impact of hydrogen production + fuel cell or EVs for long distance trucking over say algie & biodiesel. Is this really better for the environment when considering the full cost?
The one (potential) benefit could be utilizing hydrogen as a sort of battery, where off-peak electrical generation capacity is used for processing hydrogen instead of being wasted or sold at a loss. My municipality was actually paying other jurisdictions to absorb excess generation capacity, so something like hydrogen generation could be a useful off-peak demand source.
I really don't get hydrogen. Yes, it has the highest possible energy density (for chemicals) but that is about it. That is the only thing it has going for it. Everything else is either equal or worse than other options:
- It is the smallest atom so it diffuses through every other material, thus you get something similar to self discharge in batteries. Yes, you can make the walls bigger to slow down the process, but that makes it also very heavy and expensive to store.
- It only reaches its advantage of the energy density at either insanely high pressure or low temperature. Both come with their own technical challenges and make it either impractical or down right dangerous (not considering its spontaneous combustion).
- It is highly explosive and very easy to ignite. Should it ever leak and mix with air, it is bound to lead to a catastrophe. This is actually much worse than with regular gasoline or even batteries.
Now, what would be better IMO? Small / short hydrocarbons such as methane (a gas at room temperature) or methanol (a liquid at room temperature):
- Methane is still dangerous to handle, but well understood and even allowed to be used in housing. Methanol on the other hand is hard to ignite and can be mixed with water to make it inflammable, thus completely safe to store. Even this water methanol solution can still be directly used in fuel cells.
- A leak of methane is still disastrous, especially if it does not burn because of its environmental impact. However, a complete spill of methanol is barely any issue at all compared to all the other options. It quickly dilutes and is bio degradable.
- A downside is the reduced energy density, but storage is really easy and cheap so that should make up for that.
- It can easily work with existing infrastructure. Pipelines, storage tanks and trucks all exists already and methane as well as methanol are among the most traded chemicals in the world.
- Combustion engines could continue to be used, they wouldn't need a catalyst anymore and not produce any toxic gases such as carbon-monoxide. Also, the practical power efficiency of fuel cells is not that much better than that of combustion engines. Though, that might be because way more R&D optimization went into combustion engines so far.
The last two are important points, people often forget the tremendous environmental impact of completely replacing all infrastructure.
Just like hydrogen, most methane and methanol today comes from other hydrocarbons, in other words fossil fuels. However, that could change e.g. by using solar power and electrolysis / electrocatalysis. So my point is, the world should bury the hydrogen idea and go for methanol instead.
Please correct me if I am wrong in any of these points, I am here to learn ;)
People overestimate how dangerous hydrogen is. It disperses more rapidly than natural gas / propane / methane, and isn’t a liquid like gasoline.
People always think of the Hindenburg disaster as an example of how dangerous Hydrogen is, but forget that the shell was made of a chemical that is now used for solid state jet fuel.
The bigger safety issue with hydrogen is that it is a compressed gas. Modern fiberglass tanks (mostly) solve that problem by twisting apart when they catastrophically fail (instead of launching shrapnel).
I don’t know how the chemistry works for carbon-neutral methanol production, but you likely already have all the feedstock required for hydrogen generation readily available at your house (water, oxygen and electricity).
Also, commercial hydrogen crackers already exist, and are in test deployment.
The way I think about hydrogen fuel cells is that they have minimal infrastructure requirements (you don’t have to run natural gas lines / tankers anywhere, and water and electricity are more universally available), and their embodied carbon is (mostly) constant with increasing range, unlike batteries, where it’s (mostly) proportional to range.
Combustion engines are pretty crap tech compared with other options. No-one really wants to use them, and even if they did, they'd be as electricity generators in hybrid vehicles, just as any hydrogen usage would be.
The uses of hydrogen in transport would be for fleets, where they already do weird things like use CNG or recycled vegetable oil to run the engines for pollution and carbon reasons, so switching to hydrogen isn't really as big a deal as it would for home users, who are not going to be using hydrogen, because battery EVs are just so much better for that use case.
Cars (and most other tech) are going to age out, there's low hanging fruit that can be replaced now (e.g. urban driving) at a cost saving and that frees up existing ICE vehicles to be moved to other areas, to replace even older ICE vehicles that are getting scrapped because they are too costly and polluting to run.
You are correct that in future, the cheapest and cleanest sources of methane and methanol will be making them from green hydrogen (SpaceX is doing this in Texas), but there's no good reason to burn them (unless you need zero-carbon rocket fuel or kerosene) so they'll mostly be chemical feedstocks.
Hydrogen makes sense for long haul, ships, trucks and possibly airlines. Ideally we just bring back hydrogen airships. Hindenburg was primarily caused by flammable paint, not hydrogen.
The popular narrative that airships were ended by the Hindenburg disaster is a misleading oversimplification; the truth is the Hindenburg was only the final straw and helium airships had already proven themselves to be very dangerous as well. They were marginally safer, but not substantially so. Even when they didn't burn, airships were prone to being destroyed by a stiff breeze. The deadliest airship disaster of them all was a helium airship broken up by the wind, the USS Akron: 73 dead, 3 survivors. Compared to the Hindenburg's 36 dead, 62 survivors.
This said, in some of those accidents the hydrogen's flammability played a larger role in the fatalities. When R101 crashed, a lot of people survived the crash to the ground but subsequently perished in the hydrogen fire. Contrast that with the USS Shenandoah, which broke up midair in the wind. 14 men were killed but 29 survived by riding pieces fragments of the destroyed airship down to the ground.
> moving hydrogen is so hilariously in efficient though. It would have to be produced right where you fill the tank of those ships, trucks and planes.
Exactly! I see hundreds of H2 generation facilities adjacent to trucking routes near the massive wind resources of the US great plains.
Each would have a fuel stop with high efficiency H2 electrolyzers and tanks that buffer H2 using wind piwer when it's available, so intermittency won't matter, since stationary hydrogen storage is a solved problem. Hydrolysis is also a solved problem, and getting more efficient constantly (currently up to 70%). Oh, and the facility's only exhaust is oxygen.
Substitute wind with the locally abundant source of renewable energy, and presto, no shipping of hydrogen needed.
A megawatt electrolyser fits in a cargo container, so that's not as impractical as it sounds. But personally I think at least for ships ammonia is the nicer fuel.
Ammonia is so much more practical than elemental hydrogen that a hydrogen-based project inherently has the appearance of a toy. This is especially true in agricultural areas where existing infrastructure already produces and distributes ammonia in massive quantity for use as fertilizer.
Batteries aren’t an answer for anything but cars. Honestly even for cars they still aren’t a great answer. They are way too heavy and take up too much space.
There are all sorts of problems to solve with hydrogen, but I think we’re closer to solving those problems than we are to increasing battery density by an order of magnitude.
I mean that we're at the absolute edge of possible range with existing battery tech, and there is no path to dramatically increasing range. The Model 3 is 20% heavier than a Honda CRV, the "range" is about 30% less, and the total cargo capacity is also about 30% less. We can't add more batteries because the weight is already an issue, and so the only viable path forward is to dramatically increase energy density. I compared a sedan to an SUV because you otherwise wouldn't expect a small sedan to weigh so much more than an SUV.
Most effort today is going into decreasing costs via economies of scale. What's the path to an electric vehicle with a 1,500 mile range? Hydrogen "gen1" cars are already over 400 miles of range, and you can add 400 more miles of range in 3 minutes.
Basically... batteries seem more like a stopgap than a permanent solution. Do you really think batteries will ever power an airplane, for example? I do think it's plausible that planes could run on hydrogen.
For cars, they are much more than a stop gap. How will hydrogen work in cars? We need to build hydrogen filling infrastructure across the world, and then manufacture and ship hydrogen across the world.
Electricity on the other hand - we already have that infrastructure, and it basically costs nothing to move it huge distances.
We are no where near the edge of what is possible for batteries, every couple of years cars are released with 10+% more range. There is more efficiency, and chemistry to be done here.
Also hydrogen vehicles ARE EVs so how can you say batteries are a stop gap while also saying they are the obvious future… the fuel cell charges a battery, the battery delivers the energy to the motor.
>We are no where near the edge of what is possible for batteries, every couple of years cars are released with 10+% more range. There is more efficiency, and chemistry to be done here.
Nope. Not even close. The Tesla Model S had a range of 265 miles in 2012. The top end Model S today has a range of 375 miles. If we were truly extending range 10% every couple of years we would have vehicles approaching 700 miles in range on the market today.
Instead we have seen about 42% range growth paired with a 91% increase in price over the last decade. The majority of electric vehicles on the market or hitting the market in the near-term have EPA estimated range less than 300 miles.
There is no path this decade to an electric vehicle with a range that is even approaching 700 miles.
>Also hydrogen vehicles ARE EVs so how can you say batteries are a stop gap while also saying they are the obvious future… the fuel cell charges a battery, the battery delivers the energy to the motor.
You are overstating battery requirements of hydrogen fuel cell vehicle. The Toyota Mirai, for example, has a 1.24 kWh battery pack that weighs 45kg. There are also literal hydrogen combustion engines which require no batteries at all. Future hydrogen fuel cell vehicles may not require a battery at all, and may instead rely on a bank of super capacitors.
This giant heavy duty truck we're discussing has a 72kWh battery. Tesla sells sedans with bigger batteries than this.
>We need to build hydrogen filling infrastructure across the world, and then manufacture and ship hydrogen across the world.
Hydrogen can be made with water, locally. We're basically one electrolysis (or other) invention away from trivially mass manufacturing hydrogen wherever there is water. We've already solved every other problem with hydrogen.
If you're betting on BeV you're basically betting that we will quite literally never solve hydrogen production problems. I wouldn't take that bet.
BYD Seal has a rated range of 435 miles. Battery prices are also cheaper per kilowatt (The Seal is $100k cheaper than the model S). You are misrepresenting the state of play on batteries.
But according to you batteries are getting more expensive, so does that mean hydrogen vehicles are also going to suffer from this price inflation?
Electrolysis requires energy… so you think it’s more sustainable to turn energy into hydrogen then back into energy than instead just store the energy?
The well-to-wheel efficiency of an BEV is double to triple that of hydrogen, and the well in hydrogen = fossil fuel, where as the well of an BEV is renewables.
Betting on BEV is betting on the fact we already have global electricity infrastructure (which is a pretty safe bet, because it exists). And so far hydrogen at scale has involved processing methane… so just make a methane car, and stop pretending you’re being sustainable. Build the hydrogen car once you’ve solved electrolysis at scale. Because before then you’re just making another gas powered car.
The Model 3 long range is almost 1,000 pounds heavier than a Camry, and the Camry has more range (and a faster “charging” time). Interior volume is similar, with a slight advantage to the Camry, though given the Model 3 has smaller exterior dimensions I’d give it the edge there.
“Charging time” is such a bullshit term. EV means everyone has a “petrol pump” in their home. So charge time only matters on long distance driving, and we are talking 30-50 minutes per 400 miles. This just doesn’t feel like a real problem to me.
Who on an 800 mile road trip is upset about a 50 minute stop?
Sure. Electric vehicles have enormous batteries which weigh thousands of pounds and take up a substantial portion of interior volume. We’re at the bleeding edge of battery tech and the best we’re able to achieve is 300ish miles of range. We can’t realistically expand this to 500 to 1,500 miles anytime in the next decade or so.
As example compare the Model 3 and a CRV. This is an absurd example because the CRV is an SUV, but the comparison is telling given the weight differences.
The Model 3 weighs 4,200 pounds with 97 cubic feet of interior passenger space.
A Honda CRV weighs 3,500 pounds and 103 cubic feet of interior passenger space.
So we have a smaller car that is quite a bit heavier and it’s almost exclusively due to the battery. Tesla can’t cram more battery into that car so the only option is to dramatically increase energy density. There is nothing in the horizon except incremental improvements.
I think you're missing the point. 300 miles is not my ideal and, yes, change may or may not be incremental. I'd be happier with 1000m. But 300m is enough for me to buy one now. And that is progress.
And I think your point on space is out of date. I have no idea about the Tesla M3. In my mind I hate how that car looks and so I've never even tested one. But, for space, try an ioniq 5. Magic.
... yeah, but it's more than good enough for actual use, and moving away from internal combustion is important. Internal combustion cars can't go 500 miles on a tank of gas either, and trips longer than 300 miles are a tiny, tiny, tiny minority for most people.
For a large number of people. Nobody is claiming EVs are ready to replace all use cases for ICE vehicles, that would be silly. It is equally silly to point out shortcomings of EVs and say they're irrelevant in the current marketplace.
Also, level 3 charging is pretty fast - it's not as fast as filling up on fossil energy, but the bigger issue is simply one of availability. If there were even half as many charging stations as gas stations, the feasibility of longer trips would change considerably. You'd be trading a slightly slower trip for vastly reduced costs.
This isn’t true, there is no hydrogen filling infrastructure at all, not at 100 miles, 400 or 800. Power outlets… or heck even super chargers are everywhere.
“Just install a network of hydrogen filling stations, and hydrogen production facilities, and trucks that ship hydrogen daily to all of those filling stations” … ?
I heard on a podcast that this https://en.wikipedia.org/wiki/Suiso_Frontier new hydrogen tanker could only go 30 days with the hydrogen it carries. Which is why it runs on diesel. It's 40 days to Europe.
This is a solved problem, why do people persist with stuff repeated in the 1980s?!
There are endless h2 vehicles on the road. Do you think the tanks used, are apt to become brittle, and leak?!
There are h2 refueling stations for said vehicles, all over the place.
Do you think these leak, and become brittle?
And amusingly, your comment is redirecting from the claim that transporting h2 is hard. You are now poking at storage, instead of at transport (which can be done with pipelines, and is done with them).
In my case it's been at least a decade since I looked at materials science and hydrogen destroys steel isn't as well known as hydrogen blows up easily.
But ignoring this, allows the anti-h2 crowd to continue to deride h2 tech.
The heart of this often claims that h2 is polluting, based upon the fact that currently, we source a lot of h2 from Ng.
Of course this disregards that electricity is often derived from dirty sources too, meaning, all the same arguments should be levied against battery based power sources too.
What we need, is to get non polluting engine/point of use tech out there, asap! And h2 is the only tech which provides the range, due to refueling speed, to replace many applications.
Without end of use clean tech, we have zero hope.
Any environmentalist should be happy, joyful, exuberant with h2.
Sounds plausible. Is the idea to build pipes out of the same stuff? Might be worth mentioning that fibre composite essentially means epoxy with fibres in, which is not necessarily environmentally superb in the thousands of miles of pipes format.
Wonder how people will deal with burying very stiff pipes without them breaking when the ground moves. Maybe sections with rubber joints, though the joints would leak.
The Mirai needs check ups and part replacement every 5000 miles[1]. It is car sold at a huge loss (middle 5 to low 6 digits) because the tech is super expensive.
The question is can this interval be reduced once the technology matures?
Let's look what the Miria II brings in that regard.
Compressed or chilled hydrogen storage is hard. I am huge fan of using geological structures for it (salt caverns f.e.), as they are voluminous the pressure route will be an unnecessary cost and security risk.
What is it with H2 crowd and their persecution fetish?
Before lion battery tech, in the 90s, h2 and fuel cells were the next big thing. The way to move to a pollution free engine.
All sorts of claims against h2 tech came out, such as the "there is no way to store it!", which was solved in the 90s and before!
These relentless claims, not just about storage, but anything h2 related, were used to erode public trust. BC, Vacouver had h2 buses in the 90s!
But that all failed, h2 evaporated, and who do you think pushed an endless whisper campaign back then, with said falsehoods?
It wasn't environmentalists!
Now, decades later this junk bull is repeated endlessly, by environmentalists, who ignore the buses and cars from the 90s, and all the current vehciles, and just repeat "oh, it's dangerous and you can't use h2. how silly"
Yeah. Sure. No reason for me to be upset.
So don't blame me if you get flack, for repeating oil industry lies from 30 years ago, which were not true even then.
You deserve to be hassled for this!
And now, you ignored my comment about Toyota safety verifying their cars, as it is new tech, because they want to know.
They aren't inspecting because they have to, or because the tanks are unsafe, they are doing so out of prudence, and correct procedure.
So there is nothing to improve with the next model.
If being on HN causes you this much mental anguish that it justifies hassling people.
> So don't blame me if you get flack, for repeating oil industry lies from 30 years ago, which were not true even then.
I blame you giving me flak as you are giving me flak. I was not alive nor in other ways able to influence the behaviour of companies 30 years ago.
Basic math suggests if all H2 in a Mirai where to react with 02 ignoring the energy released when compressed is 340 kg of TNT. And unlike liquid gasoline or solid batteries gaseous hydrogen will disperse enough to almost instantly release all that energy with in a second of of catastrophic tank failure.
The inspections are necessary to ensure the intactness of the pressure vessel meant to prevent that. Yet if a Miria would get hit by a train at high speed or fall of a cliff even a perfect tank won't fail catastrophically and the slow release mechanism burning off hydrogen in a controlled flame over minutes would make no difference. The tanks are unsafe in these situation. Regular inspections are needed to detect damage to tanks because those would make them as unsafe in more and more common situations the worse the tank is degraded. Regular inspection are necessary, not just because of some good will of Toyota. As for how regularly i can not comment.
> they are doing so out of prudence, and correct procedure.
Procedure on hydrogen tanks is not procedure because it is. Procedures are man made and high pressure tank (and especially high pressure hydrogen tanks) have those procedures for safety reasons. I ignored your assertion that Toyota requires these inspections and cars lose their road worthiness (at least in the EU) if they are not performed because i am utterly unconvinced that Toyota developing hydrogen cars for decades does this to gain insight into the technology or out of goodness of their heart.
> So there is nothing to improve with the next model.
If you think there is nothing that can be improved with regard to safety hydrogen cars are doomed as dead end tech. If you think that less frequent inspections wouldn't be an improvement you are out of touch with reality. Either way you seem possessed by some really vitriolic memes.
Storing hydrogen compressed is a horrible idea unless you really have to (the Miria has to, due to volume constraints of cars). Due to the fact that a catastrophic tank failure even in a small tank for cars leading to a explosion you should not place grid scale tanks to things you care about such as other grid scale tanks. This negates any volume/area advantage of compressed storage of stationary hydrogen storage and just introduces a horrible failure mode. Just store uncompressed hydrogen on sorta leak proof caverns with sensors to monitor O2 concentration.
The reason why H2 didn't take of the nineties is cost, lack of range and performance and no obvious way to improve storage and lack of infrastructure. H2 combustion cars and busses would actually be worse for the climate then gasoline cars. For H2 fuel cell cars i am not certain. Government action could have made H2 cars competitive but it did not. Oil companies would have sold the hydrogen anyway but their refineries would have become stranded assets so it makes sense to implicate them in a conspiracy against H2.
The reasons why electric cars could take of is because for the rugged early adaptors the charging infrastructure was their home and car companies only had to service highways with charging stations where ever existing electricity infrastructure made it easy. All things oil companies could not sabotage. The transition happened when it happened because Tesla started to sell cars which beat the range of hydrogen cars of the 90s handedly and provided an omnipresent charging infrastructure (the normal grid) which didn't slow down travel to much on long trips (super chargers).
It's relatively common to see hydrogen Mirai cars in Vancouver (Seattle too?), nowadays they look similar to newer Prius, they used to be pretty distinctive. You can/could buy them used for around $20K Canadian, very nice interiors (Lexus essentially). Fuel costs I think were comparable to gas (3 hydrogen stations in metro Vancouver)
H2 will be the future only because it gives Oil & Gas industries an exit strategy from hydrocarbon and all the logistics already invested around it. If that is the price that it takes for us to move forward without obstructionist lobbying and think-tank disinformation from Oil & gas industries so be it.
I appreciate the argument of energy density but there is a handful of applications (aviation?) where there is a real need for setting up all the hydrogen generation infrastructure.
Something governments really need to consider implementing are superfund cleanups of the existing tanks. While some stations ( (especially those at highways where 100+ mile trips are likely) may convert to electric or possibly hydrogen, we have only 2-3 years before 50% of 80% of trips can be "fueled" fromm home.
- The fill nozzles for hydrogen cars are insulated.
- Gas stations manage pressure tanks for propane already, with no problem.
- Automated pressure monitoring has been a solved problem since the steam engine.
- Hydrogen crackers don’t create superfund sites. If they leak, they leak water, hydrogen and oxygen.
A hydrogen cracker can just be plopped down wherever electricity and water are available. You probably need an attendant because of vandals, bathrooms, snacks, etc, like a current gas station. This is why current commercial crackers are often found at existing gas stations.
So if (as per that website) you have to replace the pipelines themselves and much of the gear, is the value of using existing pipelines really just that the right-of-ways, permitting, surveying and meta-infrastructure (roads to the pipelines, supporting construction, etc) are already in place?
If that energy could be reduced, the problem would be far easier.
Here is a free idea for anyone working on this problem:
Make it more aerodynamic. EU trucks today have flat fronts and flat back. They're super aero-inefficient. US is better but not much. The flat front and back are primarily to meet maximum length regulations, which are to allow them to navigate small streets. Bypass all this by having an inflatable front and back that auto-inflate to make a pointed front and back when going over 40 mph on a straight road. Use the same kind of construction as a SUP-paddleboard - ie. 15 psi air and thousands of cords for shape. When the truck slows down, have the whole lot deflate to leave a flat front/back.
This will ~halve energy requirements for long distance trucking, which, considering fuel/energy is ~30% of the cost of shipping goods, is a massive financial win, as well as being good for the environment!
The main barriers will be regulatory. You'll have to persuade lots of government agencies to let you run trials of such things on the road. Trucks have pretty strict regulations, and you can bet 'stick a massive inflatable on the front' is going to mean you can't meet some of them, so will need exceptions to those regulations. That in turn will mean your truck can only drive in some states or regions, which will reduce its utility.