Electrification of Transport Refrigeration Units for Temperature-Sensitive Freight: US Environmental Protection Agency Region 10 Technical Assistance Case Study

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Transportation Research Record

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Transport refrigeration units (TRUs) powered by integral diesel engines provide necessary temperature control for temperature-sensitive freight. TRU engines on trucks or trailers run while parked for temperature control (known as idling)—commonly for 40 to 60% of engine run time while at a home base distribution center. TRU engine idling is a sizable source of fuel consumption, causing air pollution, negative health effects, noise, and unnecessary cost. Electrification is a viable alternative to engine idling in TRUs parked at distribution centers, cold storage warehouses, truck stops, public rest areas, packing houses, terminals and other goods-movement facilities by adopting plug-in electric transport refrigeration units (eTRUs) with grid-supplied electricity. While electrification promises environmental and economic advantages over engine idling, adoption of eTRUs with grid-supplied electricity in the United States is slow. This paper presents results from a U.S. Environmental Protection Agency technical assistance pilot project to address market and behavior barriers of electrification of transport refrigeration to reduce TRU idling. The project findings revealed fleets often underestimate idling time and cost, while being skeptical about the long-term savings and benefits of electrification. The paper introduces a technical assistance approach to work with businesses to reduce operating costs while also reducing greenhouse gas emissions and toxic air pollution of temperature-controlled freight.


© National Academy of Sciences: Transportation Research Board 2018



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