Why Elon Musk’s electric truck is doomed to fail
At the outset of this article, I need to say that I respect Elon Musk more than any living South African. He’s a visionary and a genius. He’s the man I most want to interview, but, when it comes to his electric truck, he’s got it wrong. Horribly wrong.
This is not just my opinion. I’ve been discussing the Tesla truck with people way smarter than me, and, without exception, they all think that Elon Musk’s plan is flawed. Here’s why:
1. The batteries will be too expensive
Tesla claims that the new truck will have a range of 800 km and an energy consumption of 1,25kWh/km. According to David Cebon, Professor of Mechanical Engineering in Cambridge University*, running 800 km will require at least 1 000 kWh of energy (using Tesla’s own performance claims) – in practice a 1 300 kWh battery.
“Suitable lithium-ion batteries for electric vehicles cost at least US$ 150/kWh today and are expected to fall to US$ 100/kWh by 2021. This suggests a 2021 battery cost of US$ 130 000: approximately equal to the current average price of new heavy truck in the United States (US) (in the Class 8 category),” he notes.
2. The batteries will be too heavy
Trucking is all about payload; the more, the merrier. Thanks to the weight of its batteries, the Tesla electric truck won’t be able to carry nearly as much as its diesel-powered counterparts.
The weight of a battery correlates to the specific energy of that particular battery. As Cebon notes, specific energy depends a lot on the battery design. “It depends on the exact chemical cell used and on many design variables,” he explains.
The specific energy of lithium-ion batteries falls within a certain band: 0,1 kWh/kg to 0,25 kWh/kg. “So, the weight of a 1 300 kWh battery will be between 5,2 and 13 t,” he explains.
In weight terms, trucks in the US are relatively inefficient by international standards. A Class 8 truck in America has a maximum gross weight of 36 t, which is eight tonnes less than the equivalent truck in the United Kingdom (UK), for instance, and 20 t less than in South Africa. “US carriers must, therefore, use their maximum payload of 21 t very effectively,” Cebon notes.
Alarmingly, the weight of the battery of a Tesla electric truck is likely to constitute 25 to 60 percent of this available payload. “Even after allowing for the absence of a fuel tank and lighter electric engine this payload penalty will deter many potential users, because, practically speaking, a fleet operator might require four electric trucks to carry the same load as three diesel-powered vehicles,” he explains.
The weight of the batteries on the Tesla will be somewhat offset in Europe – where the maximum gross weight is 40 t for diesel trucks and 41 t for electric trucks, but, then again, the required battery will need to be significantly bigger to pull the heavier load.
Also, batteries will become lighter in time. According to Marco Bassi, general manager sales and marketing for Europe at Meritor, a 100 kWh battery weighed about 1 000 kg in 2010. Today, that same battery pack weighs about 667 kg (or 0,15 kWh/kg). In 2025, that battery pack will weigh about 400 kg (0,25 kWh/kg – consistent with Cebon’s numbers). However, serial production of the Tesla starts in 2019…
3. The TCO won’t be lower than that of a diesel truck
In order for any truck to succeed, it needs to offer lower total cost of ownership – or TCO. The purchase price obviously forms part of this equation; it’s most definitely a deciding factor in most purchases.
Justin Laney, general manager, central transport at John Lewis Partnership, says there is a chance that the TCO of the Tesla truck could be appealing. “The diesel price in the UK is around US$ 4,60 per US gallon, one of the highest in Europe. Trucks typically each consume US$ 60k per year in diesel.
“They last around seven years, so there could be a business case for a very high capital cost truck with very low fuel cost. Many companies are volume constrained so could perhaps take a hit on payload if a fuel saving was there. The element that will drive adoption is if there is a strong business case,” he notes.
If that business case doesn’t exist, the Tesla won’t sell – because, generally speaking, transport operators will not pay more for a “green” truck. And Cebon says that’s precisely what Tesla is asking of customers.
“Elon Musk promises that his electric truck ‘will blow your mind clear out of your skull and into an alternate dimension’. However, in the real world, a vehicle offering at most three quarters of the payload for double the capital cost does not seem a very attractive proposition for the road-freight industry,” he points out.
Eventually, transport operators will be forced to move away from diesel – because of legislation. The city of Oxford, for instance, will ban all petrol and diesel vehicles from its centre from 2020. The mayors of Paris, Mexico City, Madrid and Athens have announced that diesel vehicles will be banned from their cities by 2025. TCO versus diesel won’t be as much of an issue then – but it will still come into play as transport operators continue to focus on economics.
4. Electric trucks haven’t sold in the past
Renault Trucks produced an electric truck called the MiCity. The company sold 40 trucks and then discontinued the vehicle. Iveco has been selling its electric Daily for eight years now – and it’s only sold 100 of these vehicles thus far. The reason, of course, is cost; electric vehicles have simply been too expensive. As Cebon has noted, battery costs are dropping – but not by enough.
5. Transport operators don’t give a hoot about 0-100
Without a trailer, the Tesla will do 0 to 100 km/h in five seconds, compared to 15 seconds in a comparable diesel truck. It will do 0 to 100 km/h in 20 seconds with a full 36-t load, a task that takes a diesel truck about a minute. That’s according to Telsa.
That’s great. Drivers may think that this is ever so cool, but operators won’t care. Tesla should focus instead on the total time taken to do a trip. If Musk can persuade them that his truck will be more efficient when it comes to total trip times, then maybe operators will sit up and take notice.
6. A feasible long-haul electric truck is hard to come by (as competitors have discovered)
Lots of established truck companies have been working on electric trucks for some time. Some of these companies even have electric trucks on the road. MAN, for instance, begins field tests of its eTruck in December 2017.
It’s based on the TGM and has a gross vehicle mass (GVM) of between 12 and 26 t. Significantly, it offers the same payload as equivalent diesel models. The company is testing 4×2 derivatives, which have a 149-kWh battery and a range of up to 130 km as well as a 6×2, with a battery of 223 kWh and a range of up to 200 km.
BMW deployed an electric truck – Europe’s first 40-t, fully electric truck – back in 2015. This year, it added another two electric trucks to its fleet. Depending on the specific truck, its batteries take three to four hours to charge. When fully charged, the e-trucks have a range of up to 160 km each.
Daimler is also working on an arsenal of electric trucks. In July this year, serial production of the eCanter commenced. It has a range of 100 km and a load capacity of two to three tonnes – depending on body and usage. It has plans for electric trucks with bigger capacities, too; the Electric Truck (a fully electric truck for urban distribution of up to 25 t) and the E-Fuso Vision one (a heavy-duty, all-electric truck concept with a range of up to 350 km on a single charge and a payload of up to 11 t) are both in the pipeline.
As Cebon notes, to date, the large majority of other work on electric trucks has pertained to urban delivery applications. “These tend to be small vehicles (typically less than 14 t, in any case less than 27 t). They are designed for relatively short runs – maybe 50 to 80 km, doing deliveries within cities.
“In this application, much smaller batteries are needed and it is possible to design an electric lorry with a reasonable size and cost of battery. On the highway, lorries use much more energy and drive much longer distances – so it is much more difficult to electrify them,” he points out.
The fact of the matter is this: many other established companies have been working on electric trucks for ages – and none of them has managed to come up with a workable long-haul solution.
7. Charging the trucks is going to be a problem
Diesel may be persona non grata, but the fact of the matter is that it is cheap, accessible and it’s easy to refuel a rig. Take the situation in the US, for instance. Consider a moderate-sized interstate truck stop with, say, ten pumps. Each of those pumps can deliver about ten US gallons per minute. (That is typical of gasoline pumps at an in-town station. I imagine highway truck-stop pumps may well be faster.)
With all ten pumps going at once (not uncommon), that truck stop is delivering usable (after energy-efficiency considerations) energy at a rate comparable to electric power usage of a city of 150 000 people.
Not too shabby.
Now consider the charging of the electric trucks. If these trucks are to be charged in 30 minutes as Tesla claims, the power required for each vehicle is about 3 MW. “Each medium-sized distribution centre (DC), or warehouse would have to charge about 20 to 30 vehicles at a time (while they are loading).
This means that each would require a substation able to deliver 60 to 90 MW. That is sufficient capacity to power a city of 100 000 to 160 000 people (based on a figure of 0.5625 kW/capita). So, each DC would need a substation able to power a city about the size of Cambridge,” notes Cebon.
There’s also the issue of peak demand. What happens if 500 Tesla trucks need to be recharged in one city at the same time? In a city like Houston, we would have a problem.
However, Cebon says that it is possible to charge trucks while they’re in motion. “Siemens has developed and trialled quite a nice overhead pantograph system – called the eHighway system – which achieves this with a relatively low infrastructure cost.
Such a system could power a truck like the Tesla with a smart pantograph on the roof. Provided DCs are close to the interstate/motorway network (which they often are), then only a modest battery (less than 100 kWh) would be needed to get the vehicle from the interstate to the DC at either end. This would be a feasible way to electrify long-haul road freight in some locations – in the UK, for instance, or along the eastern seaboard of the US,” says Cebon.
Induction charging may also be an option (Solaris is using this technology to recharge its Urbino 12 electric buses). As Cebon notes, induction charging could work on any electric vehicle. “Most induction charging is done when vehicles are stationary. There has been some research into inductive charging while the vehicle is in motion, but this technology is in its infancy and has many technical problems that may prevent its uptake in future,” he warns.
So, there you have it: one or two (electric?) rays of sunshine, when it comes to the Tesla truck, and lots of serious question marks.
*In addition to being Professor of Mechanical Engineering in Cambridge University, David Cebon is a Fellow of the Royal Academy of Engineering. He is director of the Cambridge Vehicle Dynamics Consortium and the Centre for Sustainable Road Freight and he leads Cambridge University Engineering Department’s Transport Research Group and the Department’s research theme ‘Energy, Transport and Urban Infrastructure’.
He serves on the editorial boards of three international journals. Professor Cebon’s research covers the mechanical, civil and materials aspects of road transport engineering. He has authored or co-authored more than 150 papers on dynamic loads of heavy vehicles, road and bridge response and damage, advanced suspension design for heavy vehicles, heavy vehicle safety and mobility, heavy vehicle fuel consumption and the micromechanics of asphalt deformation and fracture.