In 2019 fleet management company PLM purchased a refrigerated trailer, or â€śreefer,â€ť with a solar-electric transport refrigeration unit (TRU) and hired a driver who completed a successful 2,400-mile run from Phoenix to Orlando, Florida â€” on a single charge.Â
PLM, a refrigerated trailer leasing, rental and maintenance operation, has focused on the cold supply chain since 1971, said Mike Marshall, vice president of sales, speaking during an ACT Virtual clean transportation conference session Tuesday. About 10 years ago, realizing how much time and energy was dedicated to pre-cooling, staging and loading, the company directed its customers to hybrid technology.Â
â€śToday weâ€™re ratcheting it up,â€ť Marshall said. â€śWe have confidence in a zero-emission, all- electric TRU.â€ť
Reefers get a closer look
TRUs are refrigeration systems powered by internal combustion engines. Basically, they keep food, pharmaceuticals and other temperature-sensitive items cool as they are transported by trucks, trailers and shipping containers.
A key component of the supply chain, the systems nevertheless face increasing scrutiny as they are responsible for a significant portion of commercial transportation emissions. In many cases, distribution centers and grocery stores use reefers to store overflow goods, concentrating emissions in those locations.
As a result, clean air regulators are cracking down on TRUs, even as shippers and fleets seek out innovative technology to reduce energy costs and meet their own sustainability targets.Â
California leads the charge
Most of the reefer emissions and cancer risk come from the diesel engines that continue to run when the units are stationary, â€śwaiting for warehouse access or keeping turkeys frozen behind grocery stores,â€ť said ACT Virtual panelist Leah Yamashita, a staff member at the California Air Resources Board (CARB).Â
Aiming to curb pollution from these systems, CARB is working on new rulemaking that would mandate zero-emissions TRU technology at certain facilities as well as establish the necessary charging infrastructure.
The regulation, currently in the development stage, would require smaller truck TRUs to be fully zero emission, while trailer TRUs used in long-haul transportation would need to use either electric or hybrid technology, with the latter plugging in when stationary for more than 15 minutes at certain facilities in California, according to Yamashita.
Other requirements include installing electronic telematic systems to monitor compliance, and using refrigerants with lower global warming potential.
As regulations move forward, so do OEMs
â€śThe system is a complete turnkey zero-emission package for the refrigeration transportation market,â€ť said Ian Fox, product manager for the refrigerated van unit.
The trailerâ€™s proprietary molded structural composite technology, he said, dramatically improves thermal efficiencies, allowing fleets to either downsize the batteries required to haul cargo, or run longer than conventional trailer that use the same battery-powered system.
Solar panels on top of the roof feed power back to the battery pack, extending the range of the system. Depending on the day and temperature, according to Fox, the solar panels replace 60% of the trailerâ€™s energy needs.
Noise reduction is another benefit. The engine on the refrigeration unit is one of the louder components, Fox explained, and by removing the engine, â€śyou eliminate the sound associated with the engine running.â€ťÂ
Finally, removing diesel from the refrigeration unit means many maintenance headaches and costs simply disappear. â€śNo more fuel filters, no more oil filters, no exhaust,â€ť he said.
Easing into the transitionÂ
PLMâ€™s all-electric unit, manufactured by Advanced Energy Management (AEM), is available for tests and trials, said Marshall.
Among the considerations fleets need to mull is charging infrastructure. â€śItâ€™s a must,â€ť he said. â€śYou canâ€™t be successful launching this without it.â€ť Fleets need to think about placement of chargers and how many dock doors need to be electrified, he said.Â
Echoing that assertion, CARBâ€™s Yamashita pointed out the electric TRUs are not a new technology. â€śBut their use is not widespread,â€ť she said, â€śbecause of the lack of infrastructure.â€ť The California regulation assumes about 6,000 charging facilities would be required to meet the boardâ€™s refrigerated trailer emission goals.Â
Once the system is installed, success is a matter of â€śculture and operational change,â€ť panelists said. PLM, for example, monitors fleets with telematics and temperature management technology, according to Marshall, and the data shows that within 48 hours fleets forget to turn off the system â€śbecause itâ€™s so quiet.â€ťÂ
CARBÂ staff will formally introduce the TRU proposal at the end of 2020, and the agency is expected to vote on the rule during its April 2021 board hearing.