Direct Use – Dehydration of onion and garlic in Nevada

Garlic gloves (source: flickr/ Tim Sackton, creative commons)
Alexander Richter 21 Jul 2019

Geothermal energy can be used directly in food processing and in this case for the dehydration of garlic and onions in the State of Nevada, U.S.

We have been publishing details about direct use of geothermal energy for some time. In a find today, we discovered a note on an interesting case of a garlic and onion dehydration plant in the State of Nevada, U.S.

It is not quite clear if the plant referred to is still in operation, but U.S. Department of Energy’s OSTI office shared these details on the plant back in 1996:

The Gunion (garlic and onion) dehydration plant, owned and operated by Integrated Ingredients, a Division of Burns Philp Food, Incorporated, uses geothermal fluids at a temperature of 306 degrees F to dehydrate 50 to 70-thousand pounds per day of garlic and onions.

The geothermal fluids are provided by Empire Farms, who has the rights for development of the resource and is the lease holder of fee land known as the Kosmos Lease. The San Emidio KGRA is located in northern Washoe County, 90 miles north-northeast of Reno, Nevada and 20 miles south of Gerlach, Nevada. Geothermal fluids exit the plant at 242 degrees F and are piped to an injection well located 3,000 feet south-southwest of the plant.

The plant location was selected not only for the geothermal resource, but also for the area’s low relative humidity. Currently, 1100-1,200 gpm of geothermal fluids, at an inlet temperature of 302 degrees F, are sufficient to provide the dryer line with ample BTU`s. Three geothermal wells drilled to depths ranging from 493 to 1817 feet produce fluids ranging in temperature from 266 to 306 degrees F. One well can easily provide the heat required by the dryer line and will be capable of providing heat for a planned three-fold expansion of the facility. The remaining two wells are used as backup, or may be used for other applications such as soil sterilization. The fluid exiting the plant at 242 degrees F may be cascaded and used for greenhouses and soil warming in the future.

Geothermal heat is also used to dehumidify onions placed in the cold storage facility. The dehydration process takes 5-6 hours to dry the product to a 4.5% moisture content. The dried product is then milled to various sizes from powder to granules. The dehydration plant operates 24 hours/day 7 days a week. Currently 80 people are employed full-time at the plant. The dehydrated onion and garlic are used in condiments, soups, sauces and salad dressing.

In an – not working article (here the cached version) – Geothermal Development Associates (GDA) in Reno, Nevada, reported on their work on the project, providing further details. According to that, the plant was in operation from 1994 to 2004, when it was shut down due to cheaper competition for dried garlic from China.

A recent tweet locally though indicates that there is still some garlic processing/ dehydration work ongoing using geothermal energy. We will investigate.

Here a presentation by John Lund, likely from around the year 2000.