Energy company eNow announced completion of five months testing with its solar-powered Transport Refrigeration Unit (TRU), “Rayfrigeration,” on a Class 7 Challenge Dairy truck in San Joachin Valley, Calif. The system leverages a 1,800-Watt solar array supplying power to a Johnson Truck Bodies TRU for a medium dairy truck operating in ambient temperatures up to 110 degrees.
The testing highlights the technology for its reduced emissions and maintenance costs over commercial diesel-powered TRUs used in the cold chain. Further developments in the technology might also lead to new solar-power options and supplementing technologies for existing climate control systems used in ground-based transportation of temperature-sensitive cargos.
The TRU’s cold plates and batteries were charged using utility power overnight, and by the roof-mounted solar panels on the delivery route. It was tasked with maintaining constant temperatures despite cyclical opening and closing of the truck doors.
The testing showed a reduction in CO2 emissions from 2,525 lbs per week using diesel-fuel TRUs to just 159 lb. using the Rayfrigeration TRU. Nitrous oxide emissions were also reduced from 7,162 grams to just 1 gram. The reduced emissions account for overnight charging, since emissions during solar power transmission were 0.
