Over the past four decades, refrigeration companies have provided cooling equipment to potato growers and agricultural companies in order to keep potato crops from spoiling during storage. These refrigeration systems must meet the unique needs of potato storage applications and therefore function best when designed for each end user’s precise application, rather than an off-the-shelf technology.
History of Refrigeration Technology
In the early 1970s, six people founded a heating and cooling company, now known as RAE Corporation, in Pryor, Okla. One of those men was Jarrell Brewer. He learned that agricultural companies were facing problems in refrigerating and storing the millions of pounds of potatoes they produced each year. After potato growers harvested their crops in the summer, they did not have a good way of refrigerating and storing the produce until it could make its way to local supermarkets. When the outside temperatures would climb too high, all the potatoes would sprout and spoil. Because of this, the potato growers and distributors were forced to shut their plants down until a new crop of potatoes could grow. Most grocery stores would run out of potatoes at some point during the year, and any produce available in markets during these times was very expensive.
In 1973, a major potato grower and processor came to Brewer and his team of refrigeration experts looking for a specialized refrigeration system that would be large enough to cool and store potatoes year-round. After a process of design and experimentation, Brewer and his team developed a never-before-seen refrigeration system that was perfectly suited for potato storage applications. In 1974, Brewer opened the first Refrigeration Systems, Inc. (RSI) office in Idaho. RSI was the first manufacturer to develop chilled water evaporative cooling equipment for large potato storage applications.
Unique Demands
The need for application-specific refrigeration technology has grown in the potato market in recent years, as temperatures have reached higher extremes and farmers have gradually lowered average holding temperatures to better prevent sprouting and spoilage.
Potato storage differs from other refrigeration applications in that systems must be designed to use outside air for part of the year—when it is cool enough to do so—and to switch to partial or constant cooling based on ambient temperatures. Growers and agricultural companies prefer to cool with outside air as much as possible to reduce refrigeration costs, but refrigeration technology must be able to reliably switch in when ambient temperatures climb too high.
Additionally, potato storage applications require that refrigeration technology be incorporated into ventilation systems, whereas most other refrigeration is standalone. By incorporating the refrigeration system into the ventilation system of a potato cellar, greater uniformity of temperatures and reliability are ensured.
Demand for this technology varies widely from year to year, given that growers’ cash flow is highly dependent on production in the commodity market. When growers experience successful crops and high market prices, they are able to grow their business, replace aging technology, and add additional refrigeration to existing storages.
Cutting-edge Technology
As a result of the specific demands of potato storage applications, wherein refrigeration systems are ideally integrated into the ventilation systems of individual storages, technology designed from the ground up is more successful in meeting growers’ needs than off-the-shelf systems. With today’s technology, each system can be customized to a specific cellar or storage space based on size, specific location and more.
For example, air-cooled condensing units have been designed with flat evaporator coils to meet the specific needs of individual customers. Each refrigeration unit’s specifications can be based on a respective owner’s needs and decades of technical expertise.
Potato storage refrigeration technology has improved over the past four decades, with better control and ease of use. The introduction of computerized technology has enabled the development of better, more sensitive controls. Rather than simply being able to turn the compressor on and off, as was the case with prior generations of equipment, modern refrigeration systems feature controls that are better able to fine-tune temperature and pressure. As a result, refrigeration systems are more efficient, leading to lower operating costs and a more rapid return on investment. In addition, many refrigeration companies have incorporated technology like variable frequency drives (VFDs) for condensing fans and electronic valves, which also increase efficiency.
Potato Storage Technology
Over the past four decades, potato storage technology has greatly evolved, from an industry with little to no refrigeration systems available, to advanced refrigeration systems that ensure limited spoilage and sprouting and enable growers to bring products to market year-round. Refrigeration systems utilize modern technological advancements to meet the specific needs of storage facilities, as well as to increase efficiency and lower operating costs.
This article appears in the November 2016 issue of Potato Grower magazine.