Preface: Most people think that electric truck makers need to tell us the specs — the battery kWh, price, performance, and so on — before we can possibly know anything about their truck. But that’s simply not true.  We know what lithium-ion batteries are capable of. And we know the kWh, size, and weight of the battery needed to move a truck of given weight a certain number of miles. 

That makes it possible for scientists to work backwards and figure out how many kWh the battery would need to be to go 300 to 500 miles, what it would weigh, and the likely price for the battery needed for a truck at the maximum road limit of 80,000 pounds. S. Sripad and V. Viswanathan (2017) at Carnegie Mellon have done just that.  They published a paper in the peer-reviewed American Chemical Society Letters at the following link: Performance metrics required of next-generation batteries to make a practical electric semi truck. 

In addition, there simply aren’t enough minerals on earth to make a transition to electric trucks and cars:

• Antonio Turiel (2021) Some inconvenient questions: An open letter
• Simon P. Michaux (2021) The mining of Minerals and the Limits to growth video

Tesla Semi in the news:

2022-12-8 Tesla Semi 500-Mile Trip Video Shows Truck May Have Had a Lower GVW Than 81,000 Lb “In the Semi delivery event, Musk did not answer how much the Semi costs, when other customers will receive their vehicles, how much it weighs, how many trucks Pepsico received, how big the battery pack is, and several other reasonable questions any other truck maker would be willing to solve. In the video, all we see is an accelerated trip. It would be great if the original video presented the Semi being weighed, which would make it more believable that it really tipped the scale at 81,000 lb (36,741 kilograms). The footage makes us wonder precisely about that”…..

2022-1-27: Tesla Cybertruck, Roadster, Semi delayed until 2023

2022: Frito Lay, a division of Pepsico, has “bought” 15 Tesla Semi trucks (pdf).  I put “bought” in quotes, because the California Air Resources Board and matching funds contributed $30.76 million dollars to buy these 15 Tesla heavy-duty battery electric tractors, as well as 6 Peterbilt electric trucks, 3 BYD battery electric yard trucks, 12 Crown lithium-ion battery electric forklifts and so on.  Hey!  That’s my California tax dollars at work, subsidizing the very large $199 billion market cap Pepsico  corporation and giving them a free “Clean and Green!” reputation.  How much did they pay for each Tesla?  What is the cost of charging them?  How many miles a day do they go?  Am I getting my money’s worth?  Who knows, or will ever know since they’re a private company and don’t have to disclose what they choose not to.

Alice Friedemann  www.energyskeptic.com Women in ecology  author of 2021 Life After Fossil Fuels: A Reality Check on Alternative Energy best price here; 2015 When Trucks Stop Running: Energy and the Future of Transportation”, Barriers to Making Algal Biofuels, & “Crunch! Whole Grain Artisan Chips and Crackers”.  Podcasts: Crazy Town, Collapse Chronicles, Derrick Jensen, Practical Prepping, KunstlerCast 253, KunstlerCast278, Peak Prosperity

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Authors S. Sripad and V. Viswanathan felt compelled to write their paper because there are so many guesstimates of the likely cost and performance of an electric class 8 semi-truck in the media. But these hasty calculations don’t take into account critical factors like the specific energy density of the battery pack, vehicle weight, drag, rolling resistance, battery kwH to go a given distance, and weight of the batteries given current Li-ion battery technology.

The average class 8 truck, empty, weighs around 31,000 to 37,000 pounds. The tractor (the cab in front) weighs around 17,000 to 20,000 pounds.  If you subtract 4,000 pounds of power-train weight (diesel engine, cooling system, transmission, and accessories), the cab of the truck, where the driver sits, is about 13,000 to 17,000 pounds. The authors agree: they estimate “the average empty truck weight is 6,000 to 8,000 kg (13,228 to 17,637 pounds) without the weight of the engine”.  They also imply that the empty truck weighs 13 to 17,000 pounds later on when they point out that the battery for a 600 mile range would weigh 18 tons (36,000 pounds), “twice as much as the empty vehicle”.

But oops! They forgot to add on the weight of the empty container and chassis where the payload is.  That adds another 16,000 pounds (8,000 pound empty 40 foot container, 8,000 to 10,000 pound trailer, i.e. chassis).

So my weight estimate of 29,000 pounds is closer to what a class 8 electric truck will weigh. This is why my estimates of payload are always about 10,000 pounds less than the authors.

Authors: 900 miles payload of 8,000 pounds, my payload minus 3,000 (it’s overweight by 3,000 pounds).

Authors 600 miles payload of 24,000 pounds, my payload 15,000 pounds.

Authors: 300 miles payload 44,000 pounds, my payload 33,000 pounds.

If the authors are also using the average payload, which is 75% of the maximum payload, which is what I use, that would further explain the difference. I think the maximum should be used because in the future, both electricity and diesel are likely to be more expensive, or even rationed.  To maximize efficiency businesses will have to stop just-in-time delivery with half full trucks, and turn to full loads and inventories to stay in business.  And a lot less packaging so products don’t “cube out”, fill up the truck before a maximum weight can be achieved.

Nor can electric trucks be made lighter with aluminum or carbon fiber. They’re too expensive.

Unlike cars, where the average income of an electric car buyer is $148,158 (NRC 2015), and the amount of aluminum needed to light-weight the car is a small fraction of what a truck would require, the trucking industry is a cut throat business with razor thin profits.  Light-weighting is out of the question.

The maximum weight of a truck allowed on the road is 80,000 pounds, so if the body weight of a diesel truck is the minimum 33,000 pounds, then the maximum amount of cargo that can be carried by a diesel truck is 47,000 pounds.

Since an electric truck weighs 4,000 pounds less, that ought to shoot up to 51,000 pound payloads.  But it doesn’t because the battery packs weigh so much. For example, the authors found that the weight of the battery pack needed for a truck to go 900 miles is 54,000 pounds. There goes the payload: 54,000 + 29,000 truck weight is 83,000 pounds, over the 80,000 pound road limit. And this truck that can not haul cargo will set you back $500,000 to $650,000 dollars for the battery alone.

A 600 mile range isn’t commercial either. For starters, the battery pack would cost $320,000 to $420,000 dollars, and on top of that you’ll need add another $100,000 for the body of the truck.

To move a truck 600 miles requires a 36,000 pound battery + 29,000 pound truck weight and the truck can only carry 15,000 pounds, which is 32,000 pounds less than a diesel truck can carry. Musk claims the range of the Tesla semi truck can be as much as 500 miles.  Based on the figures in Table 1, that means the battery would cost $267,000 to $350,000 (also add on $100,000 for the truck body), and the battery will weigh 30,000 pounds + 29,000 pound truck weight and be able to carry only 21,000 pounds of cargo, which is 26,000 pounds less than a diesel truck.

Even if the range is on the low end of 300 miles, the battery will still be very heavy, with a battery weight of 18,000 pounds + 29,000 pounds truck weight and and only be able to carry 33,000 pounds of cargo, which is 14,000 pounds less than a diesel truck.

The bottom line according to the authors, is that a 600 to 900 mile range truck will use most or all of their battery power to move the battery itself, not the cargo. The cost of the battery is $160,000 to $210,000 plus $100,000 for the truck cab and trailer (minus powertrain), so overall $260,000 to $310,000, which is $140,00 to $190,000 more than a new $120,000 diesel truck and considerably more than used diesel class 8 truck, which can cost as little as $3,000.

If anyone in the trucking industry is reading this, I’d like to know if a 300 mile range with just 18,000 pounds of cargo is acceptable.  I suspect the answer is no, because the Port of Los Angeles explored the concept of using an all-electric battery drayage (short-haul) truck to transfer freight between the port and warehouses, but rejected these trucks because the 350 kWh battery weighed 7,700 pounds and reduced cargo payload too much.

Nor was the 12 hours or more to recharge the battery acceptable. Ultra-fast 30 min recharging was considered too risky since this might reduce battery lifespan, and bearing the cost of replacing these expensive batteries was out of the question (Calstart 2013). Even if a way has been found to charge a truck in half an hour without reducing battery life, the amount of power needed to do that is huge, so new transmission, voltage lines, upgrading many substations with more powerful transformers, and new natural gas generating power plants will need to be constructed.  Across the nation that’s many billion dollars.  Who will pay for that?

It shouldn’t be surprising that a truck battery would weigh so much.  Car batteries simply don’t scale up — they make trucks too heavy.  The authors calculated that a 900 mile electric class 8 truck would require a battery pack 31 times the size and weight of a 100 kWh Tesla Model S car not only because of weight, but all the other factors mentioned above (aerodynamics, rolling resistance, etc).

If the Tesla Semi or any other truck maker’s prototype performs better than this, there are additional questions to ask.  For example, new diesel trucks today get 7 miles per gallon. But the U.S. Super Truck program has built trucks that get 12 mpg. But those trucks are not being made commercially.  I don’t know why, but it could be because this achievement was done by making the prototype truck with very light weight expensive materials like carbon fiber or aluminum, costly tires with less rolling resistance, and other expensive improvements that were too expensive to be commercial.

Performance can also be gamed – a diesel truck going downhill or on level ground, with less than the maximum cargo weight, going less than 45 miles per hour with an expert driver who seldom brakes, can probably get 12 mpg even though they’re not driving a Super Truck.

Who’s going to buy the Tesla Semi, Cummins EOS, Daimler E-FUSO, or BYD all-electric semi-trucks?

Most trucking companies are very small and can’t afford to buy expensive trucks: 97% of the 1.3 million trucking companies in the U.S. own 20 trucks or less, 91% have six or fewer. They simply aren’t going to buy an electric truck that costs roughly 2.5 times more than a diesel truck, carries half the weight, goes just 300 miles (diesel trucks can go 1,800 miles before refueling).

Nor will larger, wealthier trucking companies be willing to invest in electric trucks until the  government pays for and builds the necessary charging stations. This is highly unlikely given there’s no infrastructure plan (Jenkins 2017), nor likely the money to execute one, given the current reverse Robin Hood “tax reform” plan.

With less money to spend on infrastructure, charging stations might not even be on the list. The big companies that have bought hybrid electric class 4 to 6 trucks so far only did so because local, state, and federal subsidies made up the difference between the cost of a diesel and (hybrid) electric truck.  And these smaller trucks that stop and start a lot which can recharge the battery a little make much more sense than a hybrid long haul truck, where trucks brake as little as possible.

The same will likely be true of any company that makes class 8 long-haul trucks. I constructed Table 1 to summarize the averages of figure 2 in this paper, which has the estimated ranges of required battery pack sizes, weights, cost, and payload capacities of a 300, 600, or 900 mile truck.

Table 1. All electric truck data from figure 2 of Sripad (2017).  

A diesel truck Max payload is 23.5 tons.  The max payload (cargo weight) is derived from the max truck road weight of 40 tons, minus battery weight, minus weight of the truck (17.5 tons).

Even if the Tesla semi’s are built in 2022 (the latest estimate), we won’t know until 2027 if charging in just half an hour, cold weather, and thousands of miles driven reduces driving range and battery life, if the battery can withstand the rough ride of trucks, and be certain that lithium is still cheap and easily available. The only thing going for the Tesla Semi is that electricity is cheap, for now.  But at some point finite natural gas will begin to decline and become very expensive, even potentially unaffordable for the bottom 90%.  As natural gas declines exponentially continues, all the solar and wind power in the world does no good because the electric grid requires natural gas to balance their intermittent power.

There is no other kind of energy storage in sight.  Utility-scale batteries are far from commercial.  Although compressed air energy storage and pumped hydro storage dams are commercial, there are so few places to put these expensive alternatives that they can make little, if any meaningful contribution, ever.

It may be that Elon Musk is banking on government subsidies, like the $9 million State of California award to the BYD company for 27 electric trucks — $333,000 per truck (ARB 2016), and the Ports of Los Angeles and San Pedro who will subsidize a zero emission truck that can go at least 200 miles. There are many other news stories very skeptical of Tesla’s claims and why he’s making them.  One of the best, which has additional issues than those I wrote about above is here (Randall, T; Lippert J. November 24, 2017. Tesla’s Newest Promises Break the Laws of Batteries Elon Musk touted ranges and charging times that don’t compute with the current physics and economics of batteries. Bloomberg).

References

ARB. 2016. State to award $9 million for zero-emission trucks at two rail yards, one freight transfer yard in Southern California. California Air Resources Board.

Calstart. 2013. I-710 project zero-emission truck commercialization study. Calstart for Los Angeles County Metropolitan Transportation Authority. 4.7

Jenkins, A. 2017. Will anybody actually use Tesla’s electric semi truck? Fortune.

Kane M (2021) Tesla Delays (Again) Semi Launch To 2022. InsideEVS.com

McCarthy, N. September 23, 2016. Survey: 69% Of Americans Have Less Than $1,000 In Savings. Forbes.

NRC. 2015. Overcoming barriers to deployment of plug-in electric vehicles. Washington, DC: National Academies Press.

Sripad, S.; Viswanathan, V. 2017. Performance metrics required of next-generation batteries to make a practical electric semi truck.  ACS Energy Letters 2: 1669-1673.

Vartabedian, M. 2017. Exclusive: Tesla’s long-haul electric truck aims for 200 to 300 miles on a charge. Reuters.