...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.
I wish that were the case:
https://www.thetruthaboutcars.com/2022/05/gas-war-republican...
> 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.
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.
The correct metric seems to be diesel consumed per kg/cargo mile.
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.
https://www.abc.net.au/news/2019-09-19/wind-turbine-blade-bl...
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.
https://www.daf.com/en/news-and-media/news-articles/global/2...
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.
[1] Source: https://www.bussgeldrechner.org/lkw.html (in German)
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.
Rail should absolutely be used more frequently. It just isn't well integrated with trucking right now.
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).
here's a few:
- https://patents.google.com/patent/WO2013182618A1/en
- https://patents.google.com/patent/US20170158260A1/en?q=B62D3...
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.
Isn't this only true up until around 50-55 mph? IIRC, at the speeds truckers see in the US, especially on rural highways, aero dominates.
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.
Plenty are in the US. A lot of people from other countries don't appreciate just how much open space there is to cover here.
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.
In the U.S., many tractor trailers have something similar, but they fold out on the back and underneath the trailer to make the rig more aerodynamic.
Example: https://www.fleetequipmentmag.com/wp-content/uploads/2015/03...
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.
It's the backend and the wake you cause that is the major problem.
IIRC this is why cab over designs decreased in the US (length requirements were relaxed): https://www.quora.com/Why-are-Cabover-trucks-for-the-most-pa...
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.
https://www.abc.net.au/news/2021-10-11/queensland-hydrogen-t...
Average fuel economy for cars and light trucks decreases 12% going from 50 to 60 MPH: https://www.energy.gov/eere/vehicles/fact-982-june-19-2017-s...
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.
The American Trucking Association actually endorses a nation 65 MPH speed limit for trucks, which they say would save 280 million gallons of diesel per year: https://www.fleetowner.com/emissions-efficiency/article/2166...
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.
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.
We will then eliminate all old cars by raising taxes on them beyound what any sane person would pay.
It’s coming. Total control.
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 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.
I've been in the Smokey Mountains and crawling up a hill at under 20mph.
Tons of torque, of course, but getting up a grade is a function of total energy, not just torque.
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.
So, maybe, if it was 2 minutes.
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.
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.
Ah yes, the classic comparison of a real product versus something Tesla says on a website splash page.
How long will the battery last if you do that cycle twice per day every day though ?
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.
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.
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.
Check out this fancar that set a new course record at Goodwood this year: https://www.youtube.com/watch?v=xtvT2XYlcOY
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.
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.
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.
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.
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.
So far, it is not.
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
It saves a small but noticeable amount of fuel.
https://www.nrel.gov/transportation/fleettest-platooning.htm...
After that using bio or synthetic fuels, batteries, hydrogen etc are more reasonable because they need to supply vastly less energy per trip.
(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)
This is only partially related but this NASA article says with their aerodynamic technology a truck can save almost 7000 gal of diesel a year.
If we assume (just to get ballpark numbers) a semi gets about 5mpg and drives about 100k miles a year that’s about 20k gal of fuel.
Don’t truckers (at least in the US) often own their truck? I would assume that being more of a constraint than the aerodynamic tech itself
https://www.nasa.gov/offices/oct/40-years-of-nasa-spinoff/tr...
Truck brakes are wasting energy and they are dangerous because they frequently catch fire and become non operational.
An inflatable cone could use the same type of mechanism
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.
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.
[1]: https://theicct.org/sites/default/files/publications/AERO_RR... (figure 2)
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%).
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.
Like, they're being rolled out now... Electric vehicles actually make sense in Europe (distances between most places are short).
> which are to allow them to navigate small streets
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.