Expert Insights

How Could Electrified Trucks Improve U.S. Emissions?

Carson Bristol
March 13, 2024
While much of the focus has been on passenger vehicles, electrification can bring substantial benefits for long-haul trucks. Electrifying the millions of diesel-powered trucks on U.S. roads could help the U.S. significantly reduce our carbon footprint.
electric semitruck navigating through an indoor warehouse

Electrified Trucking Explained

There’s no debate: transportation is a massive source of greenhouse gas emissions. While the electrification of personal vehicles is being closely watched nationwide, it’s important to consider other sources of greenhouse gas emissions within the transportation industry.

Medium-duty and heavy duty (MHD) trucks account for a relatively minimal 10% of vehicles on the road, but they produce significant exhaust emissions, accounting for roughly a quarter of the total produced by the transportation sector.

While less publicly monitored than personal vehicles, the medium and heavy duty trucking industry has made significant progress over the past few years in developing battery-electric trucks. Seasoned heavy-duty automakers like Daimler and Volvo already have electric big-rigs on the market, and newer entrants to the U.S, market like BYD and Tesla aren’t far behind, promising semi-trucks that offer impressive range and appealing benefits.

While there are drawbacks to battery-electric powertrains that make electrified trucking particularly difficult – range concerns being primary among them – electrified trucking offers considerable upside, including an overall lower total cost of ownership due to fuel savings, available government incentives, improved safety ratings, and significant environmental and human health benefits.

Large Electric Truck Parked

Many Trucks Can be Electrified

While limited range might imply that fully-electric powertrains and MHD trucks won’t mix well, more trucks on the road today are capable of being electrified than one might think. According to research conducted by the Rocky Mountain Institute (RMI), 60 percent of medium-duty and 43 percent of heavy-duty trucks are electrifiable.

RMI considers a truck “electrifiable” if it travels fewer than 300 miles before returning to its home base. Indeed, many of the trucks on the road today are short- and medium- haul trucks that return to a depot at the end of the day. Many trucks spend just eight hours per day on the road, while they spend an average of 16 hours parked at a depot – offering ample time for the vehicle’s battery to charge.

State Policy is Driving Adoption

While the electrification of a good chunk of medium- and heavy-duty trucks may be viable, there are very few on the road today. Adoption is slow, with battery-electric trucks accounting for under 1 percent of new MHD trucks in 2022.

But, certain states are adopting legislation that commits to significantly higher adoption rates in the coming years. Currently, 15 states have signed an agreement pushing for 30 percent of new MHD trucks to be electric by the year 2030, with 100 percent electrification of MHD trucks by 2050.

While this may seem ambitious given current adoption rates, the emissions reduction potential is massive – largely due to the disproportionate contribution of MHD trucks to the transportation sector.

electric truck with man on scooter in frame

Electrified Trucks: Impact on Emissions

Transportation accounts for more of the country’s greenhouse gas emissions than any other sector, and any avenue for reduction should not be overlooked. But, what would widespread adoption of electrified MHD trucking look like in terms of greenhouse gas emissions?

While it varies depending on the specific model and regional grid’s electricity mix, the International Council on Clean Transportation estimates that a fully-electric truck can produce 63 percent lower lifetime emissions than a standard diesel model. If the 30-percent electric MHD truck target is achieved, this would result in an almost 5 percent reduction in total transportation sector emissions.

While this may seem relatively insignificant in the grand scheme of things, a 5 percent reduction in the country’s largest emissions sector is nothing to sneeze at, particularly in an innately emissions-heavy, yet critical industry like medium- and heavy-duty trucking.

Plus, emissions reductions can only grow from there. Increased adoption of electrification beyond 30 percent will continue to drive emissions lower, and the continued progress towards moving away from a fossil fuel-dependent grid will maximize emissions reduction by reducing fuel emissions to close to zero.

If the grid were powered by 100 percent renewable energy, the reduction in transportation emissions would increase from 4.7 percent to 6.9 percent under a 30-percent electrified MHD trucking scenario. And 50-percent adoption of battery electric medium- or heavy-duty trucks powered by a clean grid would result in a reduction of close to 11 percent for the transportation sector.

These reductions are within reach, given the current state of the technology, but adoption rates need to begin increasing if the emissions savings are to be realized.