How One Grower Is Heating His Greenhouses This Year

To combat the single largest expense of owning and operating greenhouses, Dick Kearley of Robrick Nursery in Hawthorne, Fla., looked to the forest.

“I was inspired by the rising cost of fuel to find some sort of alternative,” Kearley says. “Then I began looking at wood for the alternative.”

When he first began looking at conventional wood-burning stoves, Kearley found the price to be astounding. Instead of paying around $30,000 for the equipment, he came up with a plan to go with something basic and low-tech. With a water stove, the simplified unit is essentially a fire box surrounded by water. The heat gets transferred to the walls and the water heats the greenhouse.

His initial problem appeared to be solved, but after using the water stoves for two to three years, Kearley wanted to improve efficiency. He had been learning about wood gasification, the process of converting organic materials into carbon monoxide, carbon dioxide, hydrogen and methane by reacting it at high temperatures.

Kearley thought this could be a good way to address the heating and efficiency issues. At that time, however, no one was willing or able to build a gasifier that could heat a greenhouse.

“Many people didn’t feel like it was worth it to build one,” Kearley says. “So I took what I was reading and went out to go build one.”

What Kearley ended up with was a piece of equipment that used unprocessed wood to gasify the greenhouse with a water heater backup. If the gasification failed, vents could be opened so the water heater would heat the greenhouse conventionally.

With his new design, Kearley saw savings of 80 percent. Although that figure is normally the attention-grabber, there is another number to keep in mind: the nursery owner estimates that 75 percent of the heat is generated by the gas and the other 25 percent comes from the fire box.

“It gives me goosebumps every time it lights up,” says Kearley.

Another benefit Kearley sites is creating minimal fuel waste. Whereas a coal-burning model might create 40 to 50 pounds of charcoal, the gasification stove turns out a mere 20 pounds of ash. The reduced smoke output also makes the stove a much greener option.

One positive that surprised the amateur inventor was how “controllable” his stove would be. Working like a conventional home oven, the gasification stove cycles its heat.

“It doesn’t cycle as fast as the home oven, but it does the same thing,” he says. “It might pop on and off every 20 minutes or so. It shuts off and turns back on quickly. The new stove is far better in that regard.”

There is one potential downside to the gasification stove, however: cost. Although Kearley kept the specific price point a secret – he doesn’t want anyone clamoring for him to build one for their greenhouse – he notes that the price tag might make some greenhouse owners sweat.

“I will say that this stove would cost more because it has more steel. It’s a complicated structure; it has 14,000 pounds of steel and 200 pounds of welding wire,” Kearley says.

Learn more about Robrick Nursery at www.robrick.com.

Leave a Reply

2 comments on “How One Grower Is Heating His Greenhouses This Year

  1. I'd really like to see more about the heating system using wood for fuel and water pipes to hold the heat….any pictures of this fellows system????

  2. The trick for gasification is to keep the fuel particle size consistent.

    Wood chips are the most common fuel; and they need to go through a drum sorter.

    That means having a huge source of wood chips or your own hog mill.

Latest Stories
Basil Planting feature

March 29, 2017

How You Can Embrace Greenhouse Food Production With Con…

Maintaining balance, learning continuously, and seeking support will help make your transition into producing greenhouse food crops a smooth one.

Read More
California Coast

March 28, 2017

How to Follow the Greenhouse Grower Team During Califor…

California Spring Trials 2017 kicks off in less than a week, and our team at Greenhouse Grower is making final preparations before we depart. Find out what’s in store during this busy but fun adventure!

Read More
Cyclamen Allure

March 28, 2017

Blooming Potted Plants for 2018 From California Spring …

We asked breeders to give you a peek at some of the great blooming potted plants they’re introducing this year at California Spring Trials. These new varieties will show up on the retail market in 2018.

Read More
Allan Armitage Of Naked Ladies and Forget Me Nots

March 28, 2017

New Book From Allan Armitage Features Stories of Plant …

“Of Naked Ladies and Forget-Me-Nots” offers Allan’s recollections of the origins of unique plant names, as well as how many plants factored into historical events.

Read More
Hydrangea paniculata First Editions Diamond Rouge (Bailey Nurseries)

March 28, 2017

Shrubs, Subshrubs, and Groundcovers from California Spr…

We asked breeders to share with us pictures and information on some of the shrubs, subshrubs, and groundcovers that you'll see at California Spring Trials 2017. They didn't let you down.

Read More
labor-supply-and-quality

March 27, 2017

Your Help is Needed to Save H-2B Returning Worker Exemp…

AmericanHort is leading the charge on this effort, but you can also help by contacting your elected officials via phone calls and social media, or by sending AmericanHort your personal story.

Read More
Pythium

March 27, 2017

Florida Ornamental Growers Took a Hit in 2016 Thanks to…

While damage figures from the 2015-2016 winter rains are still being compiled, researchers have found that Phytophthora and Pythium caused severe destruction in many plants.

Read More
Argus Multi-Feed RM - feature

March 26, 2017

Feeding System Allows For More Precise Delivery of Nutr…

Argus Controls’ Multi-Feed RM100 is designed to help producers custom-feed their plants based on specific nutrient recipes.

Read More
If your Wi-Fi is truly secure, your staff can help customers on the sales floor starting today

March 25, 2017

What Marketing Approach Can Attracts the Most Customers…

Inc.com surveyed more than a thousand customers to find out which marketing strategies worked best to entice them to try out a new business

Read More
Leanne Kenealy, Hoffman Nursery

March 24, 2017

New Horticulturist At Hoffman Nursery Will Focus On Dev…

Leanne Kenealy, who brings great experience in plant evaluation, says introducing consumers to new plants can hopefully generate renewed excitement for gardening.

Read More
GrowSpan Series 1000 Greenhouse (GrowSpan) feature

March 24, 2017

New Greenhouse Structure Models Emphasize Crop Protecti…

Manufacturers of new structure models say they are responding to grower concerns with designs that focus on ventilation, maximizing your space, and incorporating a wide range of crops. Here’s a look at some of their latest offerings.

Read More
GCA Summer Tour 2017 Andersons Newport Beach

March 23, 2017

Garden Centers of America Unveils Stops on Its Summer T…

Registration for the event, which includes visits to several garden centers each with their own unique highlights, is now open.

Read More
Bee on Lavender feature

March 23, 2017

Allan Armitage: Plant Consumers Don’t Talk About …

Allan Armitage says it's time to get in touch with our true audience and market plant solutions, not plant products.

Read More
Aspabroc Broccolini Sakata Vegetables Feature

March 22, 2017

Growing Tips for Sakata Vegetables’ ‘Aspabroc’ Br…

‘Aspabroc’ resembles a broccoli raab with an asparagus stem, has a mild taste, and requires little growing space.

Read More
Spin Top Gaillardia Series (Dummen Orange)

March 22, 2017

New Perennials and Tender Perennials for 2018 from Cali…

We asked breeders to share with us pictures and information on some of the true perennials and tender perennials that you'll see at California Spring Trials 2017. Here's a sampling of some of the varieties hitting retail shelves in 2018.

Read More
National Garden Bureau New Website

March 22, 2017

National Garden Bureau’s New Website Features Mobile-Fr…

The new site is designed to serve as a home base to drive traffic from NGB’s social media community to one central location.

Read More
Emerald Coast Growers Seed RoomTight feature

March 22, 2017

An Inside Look at Emerald Coast Growers’ New Seed…

Florida-based liner producer Emerald Coast Growers custom retrofitted and expanded an existing greenhouse, with the goal of increasing production efficiency.

Read More

March 21, 2017

How Greenhouse Vegetable Growers Can Prepare for a Prod…

The United Fresh Produce Association is holding a Recall Ready Workshop in April that is designed to help growers properly manage a recall, from liability to communications.

Read More