A Solar Fridge for Fresh Food in Hot Climates

By Ian Randall

The University of Cincinnati responds to food shortages with solar-powered cold storage for farms.

Food shortages in India are compounded by a lack of cold-chain storage facilities, but a new solar-powered cold storage device, developed by the University of Cincinnati in partnership with industry, could put this problem on ice.

SolerCool has been designed to provide cooling at the individual farm level. The size of a large garden shed, it can be easily transported to farms on the back of a truck.

The SolerCool project is a partnership between the University of Cincinnati and three local companies – Acutemp Thermal Systems, SimpliCool Technologies International and SAS Automation – funded by a Procter and Gamble higher-education grant.

The unit derives its power from eight solar photovoltaic panels which, when in operation, deliver 1kW to charge several deep-cycle batteries. In contrast to the short, high-current bursts of starter batteries (such as those found in a car), deep-cycle batteries are designed to regularly discharge between 50 and 80 percent of their total charging capacity, without degrading.

These power reserves ensure that the compression-based cooling unit is capable of functioning both day and night. SolerCool also features a battery health monitoring system, which digitally displays status updates and can predict in advance if any battery is in danger of failing.

“A recent report by the UK’s Institution of Mechanical Engineers highlighted that in India 21 million tonnes of wheat annually perishes due to inadequate storage and distribution. Any technology that addresses this overlooked area of development is to be welcomed,” says Ann-Marie Brouder, who specialises in sustainable food systems at Forum for the Future.

Each unit may initially be somewhat expensive, at around $5,000, University of Cincinnati engineer Mohsen Rezayat told the New York Times. However, wider applications may bring the cost down. SolerCool has potential, not only in countries with hot climates, but also as a "green" alternative to existing cold-chain technologies, says Ilse Hawkins, the associate business law professor who heads up the project at Cincinnati. Plans for commercial roll-out will be finalised following further tests, she confirms.

Ian Randall is a journalist working at CERN

Photo: Dottie Stover / University of Cincinnati