In Alliance, Nebraska, winters are cold and windy. But for decades, retired farmer Russ Finch has been growing tropical fruit year-round, without an energy-intensive heating system.

“We have 13 varieties of citrus: lemons … limes, tangelos, tangerines, you name it,” he says.

Finch heats his greenhouse with a geothermal system that takes advantage of the consistent temperatures eight feet underground.

He first experimented with geothermal energy 40 years ago when he was building his home. He devised a system that pulls air from underground tubes where it’s 52 degrees Fahrenheit all year.

It worked so well that he installed a similar system in his greenhouse.

Fans circulate the air, but that’s the only part of the system that uses electricity. So it’s good for the climate, and Finch says the greenhouse costs less than a dollar a day to run.

“We’ve taken the cost of energy completely out of the equation,” he says.

Finch is almost 90 years old, and he’s still growing fruit year-round.

And now he’s helping more people do the same. He sells geothermal greenhouse-building kits, so other small farmers can grow citrus in the snow.

Reporting credit: Stephanie Manuzak/ChavoBart Digital Media.