In 1941 the first early type of air-conditioning came to the reefer when the Pacific Fruit Express Company developed an alternator-driven fan system (which was powered via the car's moving axle). This system pushed air in large quantities through the ice bunkers and out of vents located near the ceiling, helping to better cool the car's contents. Around this same time better insulating techniques were developed, such as rubber seals along the car's interior seams helped to keep even more outside air out, thus farther preserving the perishable contents. However, it was the frozen-food industry of the 1950s that ultimately ended the reefer's dominance in moving perishable food. Now, everything from vegetables and meats to the new "TV dinner" could be kept frozen and, generally, fresh for weeks at a time before they were eaten. The traditional ice-cooled refrigerator cars could not keep these perishable products completely frozen, which obviously created a big problem.
Thus, the mechanical reefer was developed to alleviate this issue. The car was first successfully built and operated by the Fruit Growers Express Company just after World War II, which transported mostly southern citrus fruit from Florida to the Northeast. The FGE's original car fleet used on board gasoline-powered engines to operate the refrigeration equipment. However, with the development of the diesel-electric locomotive and its widespread use occurring around the same time the company soon engineered their cars to directly pick up the electricity created by the alternator powered by the locomotive's prime mover.
The development of mechanized refrigerator cars allowed for them to become much larger and carry a greater yield of product. However, following World War II reefers slowly saw decreasing use throughout the industry. The entire fleet had peaked in 1930 at 183,000 but by just 1950 had dropped to under 128,000. Then, by the 1970s railroads began to severely reduce or outright eliminate less profitable LCL and short-haul traffic, further reducing the reefer fleet. To make matters worse, the 1970s also saw plummeting and unreliable freight service across the industry.
Of particular note was the Southern Pacific, a system which had dominated the perishable market in California throughout most of the 20th century and prided itself on moving this freight fast and efficiently to eastern markets. It had small branch lines and spurs snaking out to serve virtually every major farm in the San Joaquin Valley. However, by the 1970s poor management saw service become so bad that entire trains of perishable traffic were rotten by the time they reached the east coast. Unable to withstand such losses California growers switched to trucks, which were more expensive but also more reliable. For more reading about the history of the refrigerator car please click here.
The SP lost virtually its entire perishable traffic business in just a few years and the skeletons of its dominance in the valley can still be seen by the many abandoned spurs and loading facilities. Growers lost so much confidence in moving their product by train that in just the last five or 10 years have they begun to again try rail service, which in tests have actually proven to be quite successful. By 2001 the refrigerator car fleet in the United States had dropped to an all-time low of around 8,000 cars. However, today that number has rebounded to over 25,000 as farmers and growers have regained a level of trust in railroads to again move their precious product by rail. For additional reading about the reefer please click here.
For more reading about refrigerator cars consider the book, Freight Train Cars, from Mike Schafer, one of the leading authors covering all corners of the railroad industry (from its history to present day operations). The book gives an excellent general history and overview on all of the common freight car types and if you are interested in learning more about them, or you are simply looking to better understanding their history and development you should very much enjoy Mr. Schafer’s book. If you're interested in perhaps purchasing this book please visit the link below which will take you to ordering information through Amazon.com, the trusted online shopping network.