“Reefers, or refrigerated trailers, are cooled by diesel fuel, with electricity from either the tractor’s generator or an Auxilary Power Unit (APU) mounted on the trailer. An idling diesel tractor burns a gallon of fuel per hour; an APU, 4/10ths of a gallon. According to XL Fleet, which makes “electrification solutions for commercial and municipal fleets,” about 50,000 diesel-powered reefers are sold every year in the U.S.
XL Fleet recently announced it is working with eNow, which makes solar and battery systems for electric Transport Refrigeration Units (eTRUs).
“XL Fleet and eNow are collaborating on the design and development of the system that will power eTRUs, as a replacement for conventional diesel-powered systems. XL Fleet is developing the high-capacity integrated lithium-ion battery and power electronics technology that will be installed underfloor on the Class 8 trailer, providing approximately 12 hours or more of run time between charges. eNow will integrate this system into its architecture, including solar panels mounted on the roof of the trailer to maintain the battery charge and extend operation.”
According to the press release, “each conventional diesel power refrigerated trailer can use as much diesel as a delivery truck uses in a day, so there are large opportunities for diesel and emissions savings with electrified refrigerated trailers.”
This got our attention since the question of the carbon footprint of imported versus local food has long been a controversial issue on Treehugger. We asked for the data behind the statement. Tod Hynes, Founder & President of XL Fleet, tells Treehugger:
“Refrigerated trailer fuel consumption is highly impacted by internal and external temperatures and operating conditions. Based on customer data, trailers can consume approximately one gallon of diesel fuel per hour, and run for 24 hours (including sitting in a yard/parking lot), which totals 24 gallons of diesel fuel per day.”
It should be noted the APUs on trailers are more efficient: According to manufacturer Thermoking, they burn 0.4 gallons per hour or 9.6 gallons per day. But let’s use the XL numbers for now.
Burning diesel emits 22.4 pounds of carbon dioxide per gallon, so a trailer full of lettuce is emitting 538 pounds of carbon dioxide per day. In her research into the cold chain for my class at Ryerson University, my student Xin Shi found a head of lettuce spent an average of 55 hours in a refrigerated truck, so just cooling a trailer full of lettuce emits 1,232 pounds of carbon dioxide….”
View the whole story here: https://www.treehugger.com/electric-reefers-eliminate-millions-tons-co2-emissions-5195419