When it comes to electric vehicles overall, even beyond electric heavy-duty trucks, two major problems impede mass production and adoption: range and refueling. We have written extensively about the first one, and automotive and tech companies work around the clock to increase the number of miles an electric truck gets on a single charge. The secondary problem is arguably more important. With refueling times for electricity being many multiples of that of diesel fuel, will the infrastructure of the United States be able to withstand an electric revolution?
Longer Waits Mean Longer Waits
A trucker is driving an electric big rig and has three miles left of charge. He pulls into an electric station, with four charging stations already in use and four people in front of him in line, waiting.
Refueling with diesel to get enough energy to drive a truck for an entire day takes no longer than ten minutes, and most likely, even less time than that. However, electric refueling is a whole different story.
Tesla advertises its Semi as getting a mile on less than two kilowatt-hours of electricity, so we will use 2 kWh as the benchmark for our electricity per mile, just to be conservative. To travel 500 miles (an average number of miles traveled by a trucker in a single day), we would need 1 megawatt-hour.
How long would it take to charge a megawatt-hour? It depends on what method is used:
- Typical household outlet: 556 hours.
- Combined Charging System 1 DC: 33 hours.
- Tesla Supercharger: 4 hours.
- Tesla Megacharger: 37.5 minutes.
These numbers are very gracious, considering many factors that may slow charging down, such as outdoor heat, current battery capacity (as batteries fill, they charge slower), etc.
Back to the trucker example, if he arrives just as the four trucks charging are full and leaving, he is next in line to obtain a charge. Even in the best-outlined scenario is Megachargers, he will have to wait 37.5 minutes for a station to open, and then another 37.5 for his truck to charge. A task that would have taken less time than the FMCSA-required break when using diesel now takes over an hour to complete!
Some workarounds can be used to reduce the total time, such as having more charging stations or implementing a limit of 500 kWh for each visit, but such ideas only alleviate the symptoms of the problem, while also adding in new problems. More charging stations requires more land, and a limit only means truckers will have to come back sooner.
The total number of trucks in the nation is where the problem becomes immediately obvious: nine people needing to charge their trucks for a minimum of 37.5 minutes is an inconvenience; 2 million trucks needing to be charged every day adds up to a lot of waiting.
Even when electric heavy-duty trucks can travel a day’s worth of miles on a single charge, the need to recharge is still a glaring problem that needs to be addressed.
Many workarounds can be combined to alleviate problems. Having a more energy-efficient truck and/or higher capacity battery would reduce the amount of traffic at charging stations, as truckers would only refuel once every two, three, or four days. In the modern era, phone apps can be used to schedule appointments for haircuts, so the same can be done for charging stations where a trucker uses an application to reserve a spot for a set amount of time without having to worry about waiting. Of course, one solution that might seem easy on paper is to increase the charge rate of the station, but a stronger current of electricity can create many more problems than it solves.
There is no straightforward solution to making electric vehicles the standard in trucking, which is why some companies are already working towards hydrogen fuel cell technology. Whatever the future of the trucking industry is, it will either be interesting to see it unfold, or boring as truckers wait for hours to charge their trucks. Hopefully, the former.