Waste-Oil Heater Keeps Greenhouse Heating Costs Low

Glenn Brendle uses a waste-oil heater to grow fresh produce all year for minimal costs.

| March/April 2016

Glenn Brendle, owner of Green Meadow Farm in Gap, Pennsylvania, makes his living by growing organic herbs, fruits and vegetables. He works with a network of 15 to 20 local farmers offering a wide array of fresh food – fresh as in harvested the previous day – to chefs across Pennsylvania. For decades, this co-op has provided a year-round banquet of delights: blueberries, honey, asparagus, eggs, cream, prime rib, sweet corn, microgreens and ham, to name just a few.

What is the key to Brendle’s success? “We owe most of it to the greenhouse vegetable-oil heating plan,” he says.

Anyone who owns a greenhouse and heats it throughout winter knows that fuel prices are a significant detriment to their bottom line during the cold months. Many a greenhouse owner, hearing the blower constantly kick on during a sub-zero winter’s day, might feel like they’re feeding the furnace with $100 bills instead of natural gas. But Brendle is able to heat 4,200 square feet of greenhouse space all year long for free. His fuel? Used vegetable oil from restaurants.

With free fuel, Brendle is able to grow not only tomatoes, but tender mixed greens, flavorful herbs, baby beets of colorful hues, and refreshing citrus and cardamom all through winter. “This makes a huge difference in my customer base,” he says.

What’s more, he gets enough vegetable oil to heat three greenhouses, the house, the shop, and his hot water. He also powers two trucks, a tractor and a skid loader on waste vegetable oil. “We’re not 100 percent off the grid,” he says, “but we’ve been running off the grid several days a week now.” Not bad!

This whole endeavor began on a winter day in 2001 when Brendle was delivering farm-grown goods to a Philadelphia cafe. Brendle noticed 25 or 30 jugs of vegetable oil languishing in the alley. The cafe owner said that a removal service used to pick up the used oil, but pickup costs were getting to be too much. Brendle took the oil, thinking he might be able to put it to use. A former engineer and self-described “piker,” Brendle thought he might try the oil in the burners of his greenhouse.

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