Megawatt Charging system being shown
Fit and ergonomics evaluation of the Megawatt Charging System connector and inlet. Photo by Dennis Schroeder, NREL Source: NREL/CharIN

An international task force says their recent high power “charge-in” event has yielded promising results with successful testing of novel connector prototypes that could overhaul the long-haul industry

In the trucking industry, speed and range count for a lot. And to this point, diesel outmuscles electrification in medium- and heavy-duty vehicles. But a breakthrough in the space could be flipping that equation on its head.

In September, the National Renewable Energy Laboratory (NREL) joined the Charging Interface Initiative (CharIN) in bringing together vehicle and electric equipment manufacturers to test prototypes for a new charging system: the Megawatt Charging System (MCS).

The test focused primarily on the fit and thermal performance of vehicle inlets and megawatt charger connectors.

“MCS enables the electrification of more truck routes and more electrified miles,” says Rustam Kocher, charging infrastructure lead, Daimler Trucks North America and chairperson of the Megawatt Charging System task force, in an e-mail interview with Electric Autonomy Canada. “The active participation by a broad coalition of over 100 companies and organizations, with a global spread, will drive us to a robust and broadly adopted commercial vehicle charging standard that will be capable of rapidly charging large battery packs on trucks, buses, boats, and planes.”

The charging specs

For perspective, electrifying one large truck on the road is equivalent to electrifying 25 passenger vehicles. In the U.S., transport made up 28 per cent of greenhouse gas emissions. Of that 28 per cent, medium- and heavy-duty trucks, planes and boats made up 34 per cent. In order to see significant results in the push to zero emissions, electrifying heavy transport vehicles is critical.

“MCS is a lynchpin to enable longer-distance electric trucks, higher utilization of electric trucks in all applications,” says Kocher. “It would mean that electric trucks could be utilized to their full capability, enabling farther distances, more freight moved, more hours of operation, and positive total cost of ownership.”

The problem the consortium set out to solve is, on paper, simple: deliver fast charging to large vehicles that travel long distances and make it compatible with all trucks. But, in practice, it’s anything but simple.

In ICE trucks fuelling happens during mandated driver breaks and occurs reasonably quickly. Prior to the development of the Megawatt Charging System, charging a mid- to heavy-duty truck battery took too long, rendering it either impractical or not competitive with ICEs or hydrogen fuel cell technology.

Enter the Megawatt Charging System task force.

“MCS is a lynchpin to enable longer-distance electric trucks, higher utilization of electric trucks in all applications”

Rustam Kocher, Charging Infrastructure Lead, Daimler Trucks North America and Chairperson, Megawatt Charging System Task Force

“This is a really exciting development. A real breakthrough,” says James Carter, a principal consultant at Vision Mobility. “Typically these things would need eight or 10 hours of charging even at very high power charging at 350kW. The aim of this group was to figure out how to do ultra high-power charging so that you could charge a very large semi within half an hour.”

That charging speed goal is an industry-wide aim, but was echoed most recently by Tesla, which is preparing to launch scaled production of its Semi, a Class 8 semi-truck, beginning in 2021.

As reported by Electrek, in a statement to shareholders last week, Jerome Guillen, Tesla’s president of automotive said the company was working to develop designated charging infrastructure for the Semi. Guillen acknowledged, “[W]e realized that the 350-kW or so that we are looking for cars is not going to be enough for Semi. So we’re looking for something much more powerful than that, that can achieve essentially charging the Semi during a break, between your driving time so that you can drive until the next break.”

Guillen would not confirm who Tesla was working with to develop a standardized charging system for heavy electric trucks, but said cryptically “We’re working with other parties to make sure that there is a standard infrastructure…we’re not working in isolation.” Tesla is listed as a member of CharIN.

How would it work

It’s likely impossible that without first developing and implementing a megacharging system Tesla will be able to maintain a fleet of their Semis. The electrical load would crash the existing infrastructure.

But how, one may ask, could such a massive electrical draw — as much as 4.5 megawatts — be supported by a grid, especially when the usage scale is not just one truck charging up, once a day, but thousands of 18-wheelers rolling and charging across the country.

The answer, says Carter, is best analogized with a trip to the water closet. Think of how a toilet works: a reservoir tank that exists alongside the rest of the plumbing in the building. It accumulates water in the tank with a slow and consistent filling process over a period of time. When the toilet is flushed the tank empties in a fraction of the time it took to fill. Then the filling process restarts, readying for the next flush.

“It is a good and viable economic model for long-distance road transport, it requires less time to recharge and allows more driving time. It also means you don’t have to worry about loading logistics, plugging in and getting a full charge at unimaginable speeds,” says Stephen Koskoletos, head of EV charging infrastructure Canada at ABB in an e-mail to Electric Autonomy Canada.

If a successful charging system is made with this model it would outstrip hydrogen fuel cell in efficiency by up to four times. The Megawatt Charging System may even be autonomous — drivers would simply pull up to the charging bay and be able to walk away which “at 20 times [the power of] a Tesla super charger,” says Carter, is probably safest.

“Once the standard is completed, we would expect federal and state programs to help accelerate public installation of the MCS standard to enable broad fleet electrification”

Rustam Kocher, Charging Infrastructure Lead, Daimler Trucks North America and Chairperson, Megawatt Charging System Task Force

Pooling resources to bring vision to reality

New ideas can, initially, come with a hefty price tag. The development process for the Megawatt Charging System is expensive and the building and rollout of infrastructure may be even more so. Luckily there is a powerhouse global team with numerous interested and supportive direct and indirect partners.

“ABB will continue to work closely with the standards committee to define the norms of the industry,” says Koskoletos. “We hope for a safe and reliable solution that offers flexibility in all vehicles and mass adoption where these vehicles are used (ports, marine, airports).”

Kocher, for his part, says he is “very confident” the task force will find a solution, but the private sector can’t do it alone.

“Many companies are already investing hundreds of thousands of dollars on design, development, and prototypes for MCS,” says Kocher. “Bringing them all together for common testing events like the NREL event is tremendously valuable to build knowledge and experience with the design, but it’s not free. Once the standard is completed, we would expect federal and state programs to help accelerate public installation of the MCS standard to enable broad fleet electrification.”