You’ll see fewer internal-combustion reefer units like this one on California roads by the end...

You’ll see fewer internal-combustion reefer units like this one on California roads by the end of 2023, as fleets must start the phased-in transition of refrigerated straight trucks to zero emissions. 

Photo: Mack Trucks 

If you need a little excitement and intrigue in your life, pay close attention to the California refrigerated transport market next year. Some refrigerated straight-truck fleets operating in California must convert at least 15% of their trucks to electric transport refrigeration units by the end of next year.

Some may not be able to meet the deadline.

The California Air Resources Board has changed the rules for mobile transport refrigeration units, commonly known as TRUs or reefers, that are mounted on straight truck chassis. CARB said it developed this regulation to address what it calls toxic and harmful emissions from diesel-powered TRUs. These include diesel particulate matter (diesel PM), fine particulate matter (PM2.5), oxides of nitrogen (NOx), and greenhouse gases (GHG).   

The rules apply to all diesel TRUs on straight truck or van chassis operating in the state, even if they are domiciled elsewhere. 

The most significant part of the rule requires operators of vans and straight trucks to turn over at least 15% of their fleet to zero-emissions refrigeration systems each year for the next seven years until they reach 100% zero emissions by 2029. The deadline for the first 15% transition is Dec. 31, 2023. Fleets that don't convert face sanctions, which can include grounding the entire fleet.  

With that deadline just over a year away, there seems to have been remarkably little discussion in the industry about it, perhaps being overshadowed by the Advanced Clean Fleets proposal. Some fleets may not be aware of the new rules. And no doubt some hope or believe that CARB will roll back the requirement, but that's unlikely. (Which brings to mind the disappointment of the many owner-operators and small fleets who believed the electronic logging device rule would be withdrawn by the incoming Trump administration in 2017.)

There is the possibility of up to a six-month extension for individual fleets due to private financing, equipment manufacture delays, or installer delays.

In addition to the zero-emissions TRU replacement rule, there also are two requirements that go into effect at the end of 2022: 

  1. Lower PM emissions for railcar TRUs, TRU generator set engines, and domestic shipping container TRUs. 
  2. The use of a new refrigerant with a global warming potential lower than 2200. The major transport refrigeration unit suppliers have made standard R452A, which has been available as an option for several years.  

Both Carrier Transicold and Thermo King say end users will notice little operational difference with this new refrigerant compound, and both say they are already in compliance with this portion of the rule. 

Sales of ICE Reefers Frozen 

One of the consequences of this rule will be to freeze sales of traditional truck-mounted reefer units in California, since the TRU rule prohibits the sale of diesel-powered refrigeration units for medium-duty trucks in California by the end of 2023.  

Fleets making purchases before then should evaluate whether it makes sense to buy a new diesel reefer unit, says Preeti Subramanian, senior product manager, truck products, at Thermo King. In most cases, it would make more sense to go ahead and buy a zero-emissions unit.

On top of that, as of Jan. 1, 2024, TRU manufacturers can no longer pull any power whatsoever off of an internal combustion diesel engine in California. That means an end to electric TRUs driven from the truck's alternator/battery system.

While the TRU must be electric, trucks can still use internal combustion engines. (There’s another rule in the works that will see zero-emission  trucks phased in at a rate of 10% per year over a prescribed period of time.) Since there are very few full battery-electric trucks available yet, there will be cases where customers will need to put an electric reefer unit on an internal combustion truck. That means the refrigeration units will need their own battery packs.  

“It would be far easier and more straightforward if the electric reefer unit always married up to an electric truck and shared the same high-voltage battery,” says Bill Maddox, Carrier Transicold senior product manager for truck and trailer. “However, our solution needs the flexibility to do that and run off its own power supply for internal-combustion applications.” 

Is the Market Ready for 2023? 

“I think there is some level of concern from customers about the transition," says Subramanian, based on what she's hearing from customer conversations with dealers.

Converting to electric TRUs is going to require significant adjustments in how fleets operate, starting with how to power an all-electric reefer unit on an ICE chassis. Obviously, it will need a battery pack of its own. It will also require charging infrastructure and power to run the unit in standby mode while it’s pre-cooling or after it’s loaded and staged for delivery.  

Some larger fleets are well into the process of installing that infrastructure. Others will be caught off-guard by the initial cost and also the wait time to have that power supply installed. 

Both Carrier Transicold’s Supra line and Thermo King’s e1000 line of electric reefers for Class 5-7 straight trucks require DC direct connections and can run off of standard industrial voltages such as 480-volt 3-phase. Subramanian says she has seen estimates of $15,000 to $20,000 for portable solutions. Installing a new 480 drop and installing a CCS (Combined Charging System) charging facility could run to the high hundreds of thousands of dollars. 

Figuring out the mobile battery capacity is another hurdle. Maddox says a typical summer day with a lot of door openings will probably be in the 20-23 kilowatt-hour range in most instances, but it will vary by the length of the route and other variables. Telematics will help determine what’s needed, but there could be fleets with a handful of trucks on longer runs or with other extenuating circumstances that will require larger battery packs, adding weight and cost.  

That could hit smaller fleets particularly hard. The alternative would be a full-electric truck from which the reefer unit could draw its power, but then you’re talking several hundred thousand dollars for the truck, the unit and the charging infrastructure.  

It won’t be easy for some fleets, especially smaller operations, to get over the initial hump of converting all or some portion of their trucks to electric. There are subsidies and vouchers available to offset a significant portion of the cost, but the time to get infrastructure projects started is rapidly running out.   

Key Elements of California’s Straight-Truck TRU Rules

Effective Dec. 31, 2023, here are the key elements of the new rules that affect trucking fleets under California’s 2022 Amendments to the Airborne Toxic Control Measure for In-Use Diesel-Fueled Transport Refrigeration Units (TRU) and TRU Generator Sets, and Facilities Where TRUs Operate. (Find the full text to the rules.)

  • Expanded TRU reporting: TRU owners must report to CARB all TRUs that operate in California, even if they aren’t based in the state. 
  • TRU operating fees and compliance labels: Fleet owners must pay TRU operating fees and affix CARB compliance labels to their TRUs every three years. 
  • Zero-emission truck TRU requirement: TRU owners must turn over at least 15% of their California truck TRU fleet to zero-emissions technology each year for the next seven years. All truck TRUs operating in California must be zero emissions by Dec. 31, 2029. 
  • Compliance extensions of up to six months will be considered for delays related to manufacturing, installation, or financing.  
  • For lease and rental customers, the rule says the TRU owner (lessors) may delegate compliance responsibility to the TRU operator (lessee) if the rental or lease agreement is for a period of one year or longer.  
  • Manufacturers of zero-emission truck TRUs will have to provide comprehensive warranty coverage and have the service network in the state to provide repairs and service.  

It's the 15% turnover portion of the rule that most worries fleets and TRU manufacturers. It’s based on the number of trucks the fleet has in service and includes a “rounding” provision that could mean some fleets need additional zero-emissions units to comply.  

There are some different deadlines for very small fleets: 

  • Single-truck operations will not have to comply until 2026.  
  • Fleets with two or three trucks will have to convert at least one truck to ZE by 2024.  
  • Fleets with four, five or six trucks will need to have at least one in service by the end of 2023, and up to two by the end of 2024.  
  • Fleets with seven or more trucks are governed by the 15% requirement.  

Editors Note: This article was edited 11/14/2022 to clarify some language.

This article appears in the November/December issue of Heavy Duty Trucking

About the author
Jim Park

Jim Park

Equipment Editor

A truck driver and owner-operator for 20 years before becoming a trucking journalist, Jim Park maintains his commercial driver’s license and brings a real-world perspective to Test Drives, as well as to features about equipment spec’ing and trends, maintenance and drivers. His On the Spot videos bring a new dimension to his trucking reporting. And he's the primary host of the HDT Talks Trucking videocast/podcast.

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