A milestone in the number of Copeland scroll digital compressors shipped from St. Louis-based Emerson Climate Technologies Inc. is being celebrated. The company has shipped its 150,000th unit since 2002.

Emerson sent the compressor to the marine container industry where it will refrigerate seagoing containers of fruits and vegetables.

Digital compressor technology provides precise temperature and humidity control to maintain box temperatures to within ±0.5°F (±0.3°C). Tight control is particularly critical for perishable products like seafood, fruits and vegetables that travel in seagoing containers on vessels that encounter harsh weather.

The world’s largest producer and marketer of fresh fruits and fresh vegetables, Dole Food Co. Inc., Westlake Village, Calif., in 2005 switched almost exclusively to the use of refrigerated container systems equipped with Copeland scroll digital compressors. The units remove heat from containers that are filled with bananas in the field, quickly pulling down the temperature to the ideal level. The process results in about half the traditional energy consumption.

Emerson estimates that use of its digital scroll compressors in refrigerated containers helps the banana industry save more than $10 million in fuel costs while it reduces shrinkage and spoilage by $500 million annually. In addition, the compressors reduce carbon emissions related to banana transportation by 15 percent.