One part of batteries charging while the truck is driving is that this would be awesome for solar panels. The solar panels can be 24/7 energy instead of only when the sun shines with help of these batteries. And yes we do need a lot of batteries, but when I look at Australia for example, they use drop batteries on ground, which takes up a lot of space and is only used in one way, instead of two ways like in my idea.
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Tesla Class 8 Semi Truck Thoughts
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The energy density of sunlight vs the area available even on a big rig and trailer combined with the energy needs for driving that truck is way too small to be useful to do much more than shave off a tiny sliver of the energy used, and the added weight of the solar panels and extra equipment probably wouldn't be worth it.
There have been a number of threads about it here over the last few years, both for covering cars in solar panels as well as trucks. For doing things like running a circulation system to keep a car or truck from overheating while parked, or possibly even running a refrigeration/air conditioning unit while parked, solar cells might be able to make a significant enough contribution to be worth it.
The best sunlight you're going to get anywhere in the world is about 1.4 KW/m^2. And that's in places like Australia on a clear day. Solar panels peak out at about 33% efficiency (limited by the Physics), which gives your best energy at about 450 W/m^2. Most of the time you're going to get less than the 1.4 KW/m^2 because of the time of day, atmospheric conditions, angle of panels to the sun, dirt on the panels, etc. A stationary installation with good siting with respect to the sun get about 150-200 W/m^2, it would be worse on a moving truck with less than ideal angles to the sun most of the time.
Solar is really best for stationary installation and charge vehicles from charging stations. The low energy density is not as much an issue then.
It is an idea that seems good until you do the math.
The problem is not math, not physics. The problem is not even technology...though improvements will help tremendously, especially when you get into things like improved efficiencies from networked automation. The problem is cost. If it were free, everyone would want it.
When you do the math it is actually a very valid concept. With today's technology, cells on the roof of a fleet average american trailer would harvest 5-6% of a tractor's annual mileage (assuming an efficiency of .5 kwh/mi).
Once cost comes down to the point where vehicles can be manufactured with solar roofs that facilitate manageable ROI/IRR--which of course comes along with technological improvements that would only improve the above number, since obviously this isn't something that's going to happen tomorrow--every fleet operator is going to want a solar roof.
I'm not talking about solar panels on top of the truck, I'm talking about solar panels on top of the roof of a compagny that charges a battery and once the truck is back, you simply swap the battery of the truck and it can drive 300 miles of again. That way the truck doesn't need to wait for 2 hours till the battery is charged again. At the same time this battery can work to balance the grid, the same way as the batteries that Tesla just dropped in Australia.
So both the roofs, as well as the batteries are double used.
When you scale this up, 50 compagnies, 50 roofs, 50 batteries outside of the batteries the trucks already got, the price goes down the solar panels can charge everything up, also the grid, also peope with normal cars that like to supercharge (enough energy availeble anyway) and so on.
And when you really really scale this up: a 1000 villages* 50 compagnies, 50 roofs, 50 batteries, 50 trucks, then all problems are solved right? Nice thing is that nobody needs to come to your house, your appartment, your place, and you still get green energy.
Compagnies with massive, perfect flat roofs already often have trucks, already use more energy as the avarage home, compagnies that put the solar panels down love big roofs, since they can make a milion dollars with just one person to speak with instead of 100 times 10.000 dollars and 100 people to speak with on 100 different locations.
I'm basically making all cities solar city's while at the same time you barely see any differences at home.
You don't see windmills where some people claim from it makes them dizzy or makes the landscape ugly, you don't hear them like windmills, you don't smell them like coal centers, no nuclear energy is there, so no people that claim to be scared of that either.
I made a pitch for something along those lines earlier in the thread, though I didn't talk about battery swap, I talked about the ability to drop the battery at a charging depot. Usually a truck is at a warehouse for a while, many times overnight. Some might have to go out quickly, but those that are planned to sit a while can leave with the battery they came in with.
Putting solar panels on warehouse roofs is already getting common, especially in sunny climates. At minimum the company can meet all their electricity needs with their own panels (with some kind of storage for night operations).
Sorry I misunderstood.
Because a railroad can only go from A to Z and skips the B C D E F and all the other places.Why don't you electrify the railroads and transport the semi-trucks for very long distances like "le shuttle". And they would also recharge whilst on them.
So even if a truck has to go from A to Q, he still has to go from A to Z and then back to Q. In that case, driving from A to Q is more fast.
They had such a "train replaces trucks" idea in the Netherlands called "Betuwelijn", in the end the line costed bilions, and nowadays the train is still driving without actually anything on it costing the Dutch taxpayers about 200 milion euro a year. Meanwhile the trucks still drive on the road, because that's way more fast and cheap.
It's the same with trams in cities, they are slower, more expensive, need all kind of (ugly) wires in the air, kill way more pedestrians, cyclists and so on compared to buses, even next to the cyclists that fall over the rails, can't break hard, can't accellerate fast, doesn't have regenerating brakes and even if they had, they would still have to put it back on the line above them which messes up the grid and powerstations, can't steer and so on and on and on. Now in the past people could say they use less energy and use cleaner energy compared to buses, but that's no longer the case, so any dime spended on a new tramline is a waste of money in my opinion. Especially if you keep in mind that a tram lasts for about 30 years according to the builders.
TBH I pretty much completely agree with this guy:
https://truckyeah.jalopnik.com/teslas-plan-to-build-a-semi-truck-is-the-smartest-idea-1784065871
I hope the swappeble battery system will have like 6 batteries for the trailer, this way smaller trucks can also use just one battery instead of 2, 4 or 6. That would make it ideal for trucks with several sizes.
https://truckyeah.jalopnik.com/teslas-plan-to-build-a-semi-truck-is-the-smartest-idea-1784065871
I hope the swappeble battery system will have like 6 batteries for the trailer, this way smaller trucks can also use just one battery instead of 2, 4 or 6. That would make it ideal for trucks with several sizes.
Reciprocity
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Can almost guarantee there won't be any batteries in the trailer, just not required. With the electric semis already announced like the Daimler/Fuso semi just recently revealed to have 220 miles of range with 300KWh pack, there is no reason for batteries in the trailer. Besides they would be to heavy and would cut the load by a tremendous amount. Battery swap might be an option for owners but I don't see it for the infrastructure, it's way too heavy handed. Elon's comments about 350KW charging be child's play and the recent patent of the automated charger that comes up from underneath the vehicle and pumps coolent points to something in the order of 700KW+ charging. If you extrapolate the Fuso numbers to Tesla where you have 30% better energy density, I could see a pack no larger then 600KWh and if we assume Tesla is also a bit better in terms of miles per KW, and assume 30% there as well, you get 600 miles of range from the 600KWh pack that can charge 80% in half an hour at 1.5c. I think drivers and companies will adapt and they will do so because of the cost savings. Part of why they push the limits now is because of costs and revenue potential, so I'm confident they will adapt. Drivers will love driving the things and all of us will love that they don't take 5 minutes going from 0-30-60 which will relieve the stress some people feel being stuck behind a semi in traffic.
Maybe Tesla makes a trailer with regen motors that can also help control the trailer, including moving a fully loaded or empty trailer around a companies terminal for staging.
One challenge will be charging at customers facilities because they may not be able to put in sufficient charging even for overnight charging, but they all have fork lifts and could potentially do battery swaps that let them cycle many packs as they charge over longer periods of time. There would be no major upgrades to power required to support this kind of charging.
600 miles of range is more then enough with 30 minute charging. And the weight of a 600KWh pack won't kill the capacity for loads.
Place your bets folks, we should know in 11 days. I'm betting 600KWh pack, no swap, no batteries in the trailer and 750KW charging at a minimum probably more like 1MW or more.
Reciprocity
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Elon said... Child's play. Now I know he is prone to exaggeration. Have you seen the drawings from the patent? The cable is like a foot thick or more and had coolent pumped through the cable and into the pack. Also could just be 6x175KW cables bundled up.. Who knows, but yes 1MW to charge 80% in half an hour.
No I haven't, could you show? What kind of person can carry a foot thick wire? Let alone plug in?
Fuso today is certainly not a class 8 truck, at least in the U.S. It's on the light end of a medium duty truck.
Tesla Semi doesn't need to do anything fancy. Batteries in the tractor with forthcoming options for capacity and charge rate will work fine. No reason Tesla can't give the customer the option of charging at 80kw for each 100kWh of capacity in the truck.
Tesla Semi doesn't need to do anything fancy. Batteries in the tractor with forthcoming options for capacity and charge rate will work fine. No reason Tesla can't give the customer the option of charging at 80kw for each 100kWh of capacity in the truck.
Reciprocity
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NeverFollow
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One possible scenario is for carriers like UPS.
Since drivers can drive about 8 to 10 hours a day and they also would like to return home every night.
I noticed that UPS has a depot half way between San Francisco and Los Angeles.
So about 200 miles and about 4 hours each way.
I don't know if they swap drivers so the driver can goes back home with an other semi truck,
or if the driver stays with the same semi truck but then the trailers must be exchanged?
I noticed that UPS connects two smaller trailers, with the second trailer using a special
fifth wheel trailer dolly attached to the first trailer, providing more delivery flexibility.
So disconnecting trailers might be common.
So with a little bit of logistic, you can have a semi truck ready to go with a full battery
when a semi arrives with an empty battery.
Unless battery pack swapping would be used, something I doubt, then depending
of the charging time at a given location and the number of truck rotations every days,
you can extrapolate how many semi trucks would be needed.
This would also includes the semi trucks who will need service,
but this would be lesser compared to diesels trucks.
I don't think that trailers will have additional batteries, while this would be easier
because there are a lot of space available under any trailer. But in this case
there should be some battery swapping removal because trailers might stay for a
longer of time in a warehouse to be loaded or unloaded.
Since drivers can drive about 8 to 10 hours a day and they also would like to return home every night.
I noticed that UPS has a depot half way between San Francisco and Los Angeles.
So about 200 miles and about 4 hours each way.
I don't know if they swap drivers so the driver can goes back home with an other semi truck,
or if the driver stays with the same semi truck but then the trailers must be exchanged?
I noticed that UPS connects two smaller trailers, with the second trailer using a special
fifth wheel trailer dolly attached to the first trailer, providing more delivery flexibility.
So disconnecting trailers might be common.
So with a little bit of logistic, you can have a semi truck ready to go with a full battery
when a semi arrives with an empty battery.
Unless battery pack swapping would be used, something I doubt, then depending
of the charging time at a given location and the number of truck rotations every days,
you can extrapolate how many semi trucks would be needed.
This would also includes the semi trucks who will need service,
but this would be lesser compared to diesels trucks.
I don't think that trailers will have additional batteries, while this would be easier
because there are a lot of space available under any trailer. But in this case
there should be some battery swapping removal because trailers might stay for a
longer of time in a warehouse to be loaded or unloaded.
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There are a lot of things that are theoretically easy, but doing it consistently on a mass scale gets difficult. Tesla has had a lot of premature wear on heavily used superchargers because they don't get a chance to cool down between uses.
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