The Koolkat: A Demonstrational Mobile Cooling Unit to Support the Development of Small and/or Urban Farms

Cooling facilities are a major barrier for small farmers in the central United States. A survey of local growers in 2014 revealed that access to proper storage facilities, especially cold storage, is one of the most frequently-encountered challenges for producers to increase local food production and implement Good Agricultural Practices (GAPs). In 2015, we found through follow-up surveys that only 32% of producers have access to quick cooling facilities, and 6% have access to refrigerated trucks. Based on these results, it is clear that more emphasis on cooling infrastructure is needed. Therefore, we built a demonstrational mobile cooler in March 2015 using a box trailer, insulation panels, and a cool-bot system with a 10,000 btu air conditioner. Structurally Insulated Panels (SIPs) were chosen for the insulation and were available locally as re-claimed materials. Unlike polystyrene foam sheets, SIPs have closed cell foam and therefore retain their R-value better during moist conditions. More importantly, the polystyrene foam is not a cleanable surface and therefore does not comply with GAPs. The SIPs we utilized have a painted metal layer on either side, and is therefore compliant. Ten, 5’x10’ panels were used for the cooler. We chose to utilize a 6’ x 12’ dual axle trailer (5’ x 11’ cooler), which could accommodate two pallets, in addition to providing substantially more weight capacity due to the second axle. The total estimated material cost for the mobile cooling unit was $6290. Once the cooler construction was complete, we were able to provide knowledge to growers as well as the general public about the benefits of proper storage temperatures.  The mobile cooling unit was featured in a number of commercial growers events in 2015-16 including a Postharvest Handling Workshop and the Commercial Fruit and Vegetable Field Day as well as the Great Plains Growers Conference. The ability for growers to be able to see the unit and look at the components has had tremendous impact.