Those who live in the Midwest United States understand how difficult it can be to eat local during winter. But for Russ Finch and his community, the task isn’t too difficult. A former mailman living in Nebraska, Finch designed a greenhouse that produces lemons, grapefruit-sized oranges, green figs, and grapes — all for just $1 a day. His magic trick? Geothermal heating.
Finch calls his structure the Greenhouse in the Snow. The original, which he constructed more than 20 years ago, is connected to his home. Finch specifically grew citrus in the greenhouse to prove that it’s possible. “Any type of plant we saw, we would put it in and see what it could do. We didn’t baby anything,” said Finch. “We just put it in and if it died, it died. But most everything really grows well. We can grow practically any tropical plant.”
NPR reports that the structure’s design is base don a walipini, or a pit greenhouse. The floor has been dug down 4 feet below the surface, and the roof has a slant toward the south to catch the sun’s rays. During the daytime, temperatures in the greenhouse can reach over 80 degrees F. At night, geothermal heat is relied on to combat the plummeting temperatures.
Only warm air is used to heat the greenhouse — no propane or electric heaters. Warm air is obtained from perforated plastic tubing that is buried underground. The tubing runs out one end of the greenhouse and extends in a loop to the opposite side. It is circulated via a single fan. “All we try to do is keep it above 28 degrees in the winter,” said Finch. “We have no backup system for heat. The only heat source is the Earth’s heat, at 52 degrees at 8-foot deep.”
Because the 1,200 square foot greenhouse is not dependent on fossil fuels, energy costs are down to just $1 a day. Particularly in midwestern states, low energy costs matter. “There have been hardly any successful 12-month greenhouses on the northern High Plains because of the weather,” said Finch. ”The cost of energy is too high for it. But by tapping into the Earth’s heat, we’ve been able to drastically reduce the cost.”
Every year, the farmer grows a few hundred pounds of fruit which he sells at a local farmers market. His main business is selling the design for the Greenhouse in the Snow. A new version of his invention costs $22,000 to build. Finch says he has constructed 17 of them so far, throughout the United States and Canada.
While Finch might not be able to supply a supermarket with the crops he grows, he can provide fresh produce to his local community. If more people in the rural midwest invested in greenhouses that rely on geothermal energy, carbon emissions from shipping fruit and vegetables all over the country would be reduced. This, in turn, would benefit the environment and people’s health as fresh, organically-grown food is more nutrient-dense and retains more flavor.