Medium- and Heavy-Duty Vehicle Electrification 101

Harry Forbes

Transportation pollution affects hundreds of thousands of people in the U.S. each year and is the highest source of climate pollution in the United States. Within this sector, medium- and heavy-duty vehicles (such as trucks, buses, and delivery trucks), tend to be especially intense polluters due to their use of diesel, spewing nitrogen oxides and particulate matter that can cause chronic heart and lung diseases as well as premature deaths. Diesel pollution is especially concentrated in urban areas and tends to be worse in low-income communities and communities of color.

To bring Americans higher air quality and better health outcomes, we must transition to a fully zero-emission truck and bus fleet as soon as possible. How do we get there? By considering the need for charging infrastructure, costs of the vehicles, and getting some help from utilities and supportive policies and programs.

Making electric trucks and buses affordable

Today, there are many options for fleets to purchase electric trucks and buses—and fleets are starting to do so.

Excitingly, major companies and fleets, like USPS, PepsiCo, and Amazon, are putting in preorders for thousands of electric trucks and delivery vans. In fact, the amount of demand for clean trucks and buses has given rise to several new companies that produce them exclusively—such as Rivian and Arrival. And even legacy manufacturers are making large commitments. Volvo, for example, is aiming for 50% electric sales by 2030. Right now, the upfront purchase price of an electric truck is likely higher than that of its diesel counterpart, which may be a barrier for smaller fleet owners. But that is changing as battery prices—the highest component of vehicle cost—are decreasing rapidly. For most MHDV classes, the total cost of ownership without incentives for electric vehicles will meet or dip below the cost of internal combustion counterparts by 2030. For example, by 2030, an electric walk-in van is expected to have a 22 percent lower total cost of ownership versus its diesel counterpart, yielding savings of $47,000 per vehicle. This is mostly due to reduced costs of fueling and maintenance for zero-emission MHDVs. What’s more, the residual cost of electric trucks is expected to be higher for electric trucks. This is mostly due to reduced costs of fueling and maintenance for zero-emission MHDVs. What’s more, the residual cost of electric trucks is expected to be higher for electric trucks.

Battery costs over time

Bloomberg New Energy Finance

While we wait for full price parity, states can use incentive programs to support the purchase of electric trucks and buses and bring down that upfront price. California and New York have voucher programs that reimburse fleet owners for tens of thousands of dollars per truck – effectively eliminating the difference in price between the electric vehicles and the internal combustion alternative. Proterra—an electric transit bus manufacturer—has another creative solution to the upfront price tag issue: battery leasing. Through their new battery leasing program, Proterra has managed to reduce the upfront cost of its electric buses to that of a diesel bus.

Charging electric trucks and buses

In addition to ensure that vehicles are available to fleets, it’s crucial that vehicles are able to recharge their batteries through electric vehicle charging stations.

One of the challenges with electrifying this portion of the transportation sector is the fact that there are so many different types of medium- and heavy-duty vehicles. And each vehicle type may have different charging needs vary based on vehicle size, usage schedule, and application. There are two types of charging available: Level 2 chargers, which charge relatively slowly (on the order of 9-15 hours depending on battery capacity), and Direct Current fast chargers (DCFC), which can charge most trucks in a few hours. Trucks and buses with smaller batteries and/or long periods of downtime between shifts are well suited for Level 2 charging. This includes many Class 2-5 vehicles, meaning anything from a pickup truck to a city delivery truck. In most states, the majority of the fleet is Class 2-3 and are a good fit for Level 2 charging. Vehicles with larger batteries or vehicles with less time to charge are more likely to need DCFC. For example, regional haul and long-haul tractor-trailers that are traveling longer distances will likely need this faster charging to “refuel” during their trip.

The National Academies Press

There is also a distinction between depot and public charging. Depot charging is when fleet owners install charging infrastructure at their facilities, where only their trucks or buses can access them. This type of charging is ideal for vehicles that are frequently returning to a home base where they can recharge, generally overnight. But medium- and heavy-duty vehicles can also take advantage of public chargers that were originally intended for passenger cars, which are becoming more and more prominent across the nation. These numbers will only increase with Biden’s proposed 500,000 charging stations to be built around the country. And the buildout of new charging infrastructure creates good, well-paying jobs.

The role of utilities

In the transition to all-electric MHDVs, utility companies have a large role to play, in concert with state agencies and private investors. Utilities can build the infrastructure needed to enable charging at both public and private charging locations. Several utilities across the nation have already started incorporating MHDV charging into their plans, with $729 million approved for medium- and heavy-duty charging. But we still have a long way to go in building up sufficient charging infrastructure—both at depots and in public. Utilities can also adjust rate structures to better reflect the flexibility of MHDV charging and help to maximize benefits to the grid and fleets. Unlike buildings, many MHDV fleets can be flexible in their charging times and can charge overnight when there is extra capacity on the grid and utilities can help facilitate this by designing rates and price signals that help to maximize the fleets fuel cost savings. They can also participate in vehicle-to-grid applications, in which the vehicles send electricity from their batteries back to the grid. School buses, for example, work well for this application because they have large batteries and a lot of downtime during the summer. In a sense, they can act as storage on wheels and improve grid resiliency.

In addition to utility action, states can enact programs, policies, and regulations to get clean vehicles on the road.

Policies and programs to support the transition

California has finalized the Advanced Clean Trucks rule, which requires manufacturers to produce an increasing percentage of zero-emission trucks. Other states can also adopt this rule, which will help them kickstart the transition to a fully zero-emission medium- and heavy-duty vehicle fleet, and states such as New York, New Jersey, Oregon, and Massachusetts, are considering moving forward with this regulation. California is also in the process of finalizing the Heavy-Duty Omnibus rule, which is primarily a more stringent cap on emissions of nitrogen oxides on new fossil fuel trucks, which are harmful to human health and can cause respiratory illnesses. California has an additional rule in the works to support zero-emission MHDV: the Advanced Clean Fleets rule, which will require fleet owners to purchase new clean trucks and buses. These three rules can work in harmony to accelerate the market for zero-emission trucks while reducing pollution from the remaining internal combustion trucks.

Last year, 15 states and Washington D.C. signed a Memorandum of Understanding to accelerate medium- and heavy-duty vehicle electrification, with a goal of 100% electrification by 2050 and interim goal of 30% electrification by 2030. California and New York both have plans to achieve 100% zero-emission truck and bus sales by 2045. Other states should follow their lead and invest in transition to an all-electric fleet to help tackle the climate crisis and improve the health of American citizens.

About the Authors

Shelby Parks

Schneider Fellow, Eastern Region, Climate & Clean Energy Program

Join Us

When you sign up you'll become a member of NRDC's Activist Network. We will keep you informed with the latest alerts and progress reports.