Viking Cold Solutions has installed one of its hybrid cooling systems at a food bank in San Diego, Calif.
The system combines rooftop photovoltaic panels and thermal energy storage to efficiently cool Jacobs & Cushman San Diego Food Bank's 80,000-square-foot warehouse.
Plastic cells filled with a salt-hydrate phase change material are arranged in modules installed above food storage racks. Solar-powered chillers solidify the PCM during the day. When the chillers are idle, the PCM absorbs heat as it melts, keeping the warehouse within its target temperature range.
The Houston-based company says the system provides sufficient cooling capacity to cut grid consumption dramatically. "Between the hours of 7 p.m. to 7 a.m.," Viking says of one six-week period, "grid consumption dropped from 168 KWh to 8.1 KWh, a 95% reduction. And peak demand from refrigeration dropped from a high of 46 kW at midday to 1 kW overnight."
The warehouse is the central food distribution hub for San Diego County, serving an average of 400,000 people each month. Last year, the food bank distributed 22 million pounds of food.