Improvements in engine fuel delivery, transmissions, and cab aerodynamics have helped semi-truck manufacturers significantly reduce fuel consumption in recent years. To go even further on less fuel, companies have also developed new add-on technologies to reduce aerodynamic drag such as trailer side skirts, wheel covers, and trailer tails (or rear fairings). Given the relatively new offerings, it would be easy to assume there are no more significant improvements to make to a typical Class 8 tractor-trailer combination.

Enter Range Energy, a startup founded in 2021 and based in Mountain View, CA, which has developed an electric trailer axle system for the heavy-duty truck market, essentially transforming a trailer into a part of a semi truck’s powertrain. The company launched in September 2022 with $8 million in seed capital and first debuted its electric drive technology for 53-ft semi-trailers at this year’s Advanced Clean Transportation Expo. It is led by a team with deep EV industry expertise from Tesla, Zoox, and Honda, and backed by investors including UP Partners, R7 Partners, and Yamaha Motor Ventures.

Since then, the folks at Range Energy have been making the case for powering trailers to improve diesel trucks’ fuel economy and electric trucks’ battery range. The concept is simple: add some electric propulsion to a trailer so it can assist—or in some cases, replace—the motor in the truck that’s pulling it, thereby reducing stress on the truck’s motor and the amount of fuel required to power it.

Earlier this month, Range Energy took another step toward validating that concept by releasing some preliminary third-party testing results, which revealed up to 36.3% fuel efficiency gains (+3.25 mpg) for semi-trucks using its electrified trailer drive system. Testing was conducted on a 25.5-mi (41-km) urban/highway loop, at about 59,000 lb (26,800 kg) gross vehicle weight (GVW), and a 60-mph (97-km/h) top speeds across multiple scenarios including stop/go and steady-speed driving situations.

“Achieving 36.3% efficiency improvements proves to the trucking industry how important and overlooked trailers are to enhancing efficiency and lowering emissions for our industry,” said Ali Javidan, CEO and Founder of Range Energy. “Range is the first electrification platform to actually prove this level of efficiency benefit, and we anticipate these numbers will only improve as we begin testing with production quality parts versus prototype components.”

The efficiency testing was conducted by Mesilla Valley Transportation Solutions (MVTS), a company that provides testing, design, and development services for the trucking industry and helps fleet operators reduce cost-per-mile expenditures and meet emissions-reduction targets.

“We were impressed with the Range trailer,” said Daryl Bear, COO of MVTS. “Whether a fleet wants to reduce fuel usage or increase BEV range, this system provides unique opportunities over a traditional trailer—and by a large amount when considering it achieved 36.3% fuel savings. Our drivers also liked the Range trailer, reporting it pulled easier and felt lighter. Naturally, there is a trade-off with electric charging and additional weight, so it may not suit every fleet, but for those considering the EV direction, Range is worth talking to.”

This past Summer, Range Energy announced its 53-ft RA electric trailer was made eligible for point-of-sale incentives up to $80,000/unit through the California Air Resources Board Clean Off-Road Equipment (CORE) voucher program, an initiative the state says puts millions of cap-and-trade dollars to work reducing greenhouse gas emissions, strengthening the economy, improving public health and the environment, and providing benefits to the most disadvantaged communities. CORE provides a streamlined voucher process by which California fleet owners and operators can receive funding to offset the cost of cleaner equipment as well as develop innovative ways to reduce pollution.

“Acceptance into the CORE program and having Range’s powered trailers included in such an innovative incentive program is a huge milestone for our team and the commercial trucking industry as a whole,” concluded Javidan. “The trailer is the most ubiquitous piece of hardware in the trucking industry, and we’re thrilled that CARB and the CORE team have recognized the meaningful impact electric-powered trailers can have as we collectively work to rapidly reduce the emissions of the commercial trucking sector.”

The RA-01 was designed to reduce diesel consumption during yard operation, at the dock, while idling, and in a multitude of other scenarios. The trailer’s electrification platform and equipment set—including an e-axle, battery pack, and smart kingpin—provides power to auxiliary devices, enables zero-emission precooling with TRUs (transport refrigeration units), provides the ability to move trailers with reduced emissions, and increases overall uptime of tractors.

Top-level system specs include a 200-kW·h energy capacity, 800-V operation and 60-A/240-V AC onboard power, and 350-kW and 14,000-N·m (10,330-lb·ft) propulsion outputs. The battery can be replenished with 19 kW (for 10.5 h) AC or 350 kW (for 45 min) DC fast charging.

 

Kevin Jost contributed to this article.