California Proposing New Restrictions to Diesel-powered Transport Refrigeration Units

The California Air Resources Board is developing yet another regulation designed to limit emissions from transport refrigeration units (TRUs), which could further impact carriers that operate reefers into California.

The California Regulation Development for Transport Refrigeration and Cold Storage is expected to outline control measure concepts for TRUs operating at a wide variety of facilities and properties across the state.

The basic concept is to “reduce the amount of time that TRUs operate in a stationary mode while powered by internal combustion engines” when they are at certain California locations, such as – but “not limited to” – grocery stores, distribution centers, fleet terminals, cold storage warehouses, truck stops, port terminals, railyards, rail sidings, intermodal facilities, produce and meat packing houses, food hubs, State and county fairs, public and private rest areas, and farmers’ markets.

The proposed allowable operating time limit for TRUs would decrease over three phases:

  • Phase I: 24 hours, effective January 1, 2020
  • Phase II: 1 hour, effective January 1, 2022
  • Phase III: 5 minutes, effective January 1, 2025

The first phase appears to target shippers, grocers and other facilities who run TRUs for additional storage capacity. However, many North American carriers operating diesel-powered TRUs in California will be directly impacted to some degree at least by 2022, regardless of whether or not they are faced with long wait times at these facilities.

CARB says stationary TRU operations could be reduced by using more efficient load scheduling technology and procedures, plugging hybrid-electric TRUs or all-electric refrigerated trailers and shipping containers into shore power, or using cryogenic transport refrigerators instead of conventional diesel engine-powered TRUs.

CTA is working closely with the American Trucking Associations on gathering more information on how the proposal would specifically affect carriers operating TRUs in the state.

A rule adoption public hearing is tentatively scheduled for late 2017. In the meantime, CARB will soon be scheduling a series of public workshops explaining its proposal and gathering comments from stakeholders. The first workshop notice will go out in the next several weeks, and which point CTA will inform members.

CARB’s full Sustainable Freight Discussion Document, in which the Regulation Development for Transport Refrigeration and Cold Storage is described, can be accessed here:

Any further questions can be directed to Marco Beghetto at

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