Greenhouse powered by geothermal energy produces fresh fruit year-round in NebraskaFebruary 22, 2016
A Nebraskan entrepreneur has designed a greenhouse that runs all year long using geothermal power.
Russ Finch, an entrepreneur, engineer and retired mailman who lives in Nebraska, has designed and developed a greenhouse that is powered by geothermal energy and can operate 12 months out of the year on Nebraska’s Northern High Plains. Finch’s greenhouse is unique, not only because it runs on renewable power and can grow citrus fruit (and other produce) year-round but, because the U.S. state is known for its bad weather, which has resulted in a lack of greenhouses in the area due to the high energy cost that would be required to effectively run these facilities all year long.
Geothermal is used to heat the greenhouse in the night.
The creatively designed greenhouse is based on a pit greenhouse, also known as a Walpini, design. The bottom of the greenhouse is dug out, so its floor is located four feet beneath the surface of the ground. The roof, on the other hand, is slanted toward the sun to capture the maximum possible amount of light and heat.
Throughout the day, the temperature in the greenhouse typically climbs well over 80 degrees Fahrenheit but, once the sun goes down, temperatures rapidly decrease. Geothermal heat is then used to maintain the warm temperature that is required to grow the plants. The warm air comes from perforated plastic tubing, buried underground, and a simple fan circulates the air in the structure.
In Finch’s design, he utilizes a geothermal system that is eight feet underground, where the temperature remains at a stable 52 degrees Fahrenheit. Tapping into this level of heat is enough to ensure that when the outside temperature gets really cold, such as during the winter months, the temperature in the greenhouse is high enough to sustain the plants.
Finch is continually receiving demands to sell his geothermal energy greenhouse design.
While it took Finch plenty of trial and error to get his project up and running and required a substantial $22,000 investment, now that it is complete, his electricity costs to run the greenhouse are only $1 per day.
After testing which type of fruits would grow best in the conditions of his greenhouse, Finch decided on figs and Valencia oranges as his chief produce to grow. Although he does make a bit of money selling his produce at local markets all year long, primarily, his profits have come from selling the actual design he crated.
Interestingly, one of his geothermal energy greenhouses is located in Alliance, Nebraska and is used by students to grow vegetables for school lunches. Presently, Finch has said that a total of 17 of his greenhouses have been built in the United States and Canada.