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
ISO-Group-Transplanter-feature

December 11, 2017

Evaluating Robotic Transplanters for Plant Cuttings

There are several factors that might affect your decision to invest in transplant robots, based on initial observations and reported information about available equipment.

Read More
Overhead-irrigation-to-maintain-moisture-content-feature

December 10, 2017

Greens Production Goes High-Tech at lēf Farms

A Finland-based company has developed two new automatic growing systems for lettuce heads and baby leaf lettuce. Learn how one grower is making it work for them.

Read More
California Wildfires

December 9, 2017

Southern California’s Wildfires Endanger Greenhouse and…

Here’s an update on horticulture businesses in the areas affected by the California wildfires.

Read More
Monitoring the plant canopy for temperature

December 9, 2017

Infrared Thermometers for Monitoring Plant and Substra…

Growers use many tools to monitor the greenhouse environment. Learn about the best practices for using an infrared thermometer to measuring plant temperature.

Read More
Weigela Czechmark (Spring Meadow Nursery)

December 8, 2017

Spring Meadow’s New Logo Highlights Focus on New, Color…

In a move that highlights its commitment to developing new, colorful flowering shrubs, Spring Meadow Nursery has unveiled a new logo.

Read More
HortScholars

December 8, 2017

HortScholars Program Now Accepting Applications for 201…

Do you know any college students currently in a horticulture-related program? This unique program gives them a chance to connect with industry leaders and make new connections at Cultivate.

Read More
Peat vacuum harvester

December 8, 2017

The Sustainability of the Peat Industry Looks Better T…

Despite talk about alternative products and differences of opinion over its sustainability as a resource, peat is here to stay.

Read More
SunStanding-New-Guinea-Impatiens-Dummen-Orange-feature

December 7, 2017

Growing Tips From a Pro for SunStanding New Guinea Impa…

SunStanding New Guinea impatiens hybrids spruce up the landscape with vibrant blooms that explode with color in both sun and shade areas, and they hold up well in heat and humidity.

Read More
Japan-Airlines-princettia

December 7, 2017

Suntory Pairs Princettia with Several Breast Cancer Awa…

Suntory Flowers is partnering with several major brands to support breast cancer awareness and fundraising, using its bright-pink Princettia euphorbias as the ideal plant for Pink Ribbon promotions.

Read More

December 7, 2017

For the Record: Differing Opinions Are Healthy

With all of the changes happening in our industry, differing opinions are healthy. Let's open up the dialog and keep it real.

Read More
mycoapply-from-mycorrhizal-applications-feature

December 6, 2017

How Mycorrhizae Provide Value at Your Greenhouse or Nur…

Mycorrhizae create a connection between the roots of a plant and the surrounding growing media. This ultimately leads to better crop health through enhanced nutrient and water uptake.

Read More
Kellee O'Reilly

December 5, 2017

We Are Not Immune: An Open Letter to the Green Industry…

We’re an industry rooted in family values, farming, agriculture, passion for nature, and faith. We are also an industry made up predominantly of men in positions of leadership. During an interesting watershed moment that is happening culturally at present, it's important for the green industry to address its own issues.

Read More
GROW-Summit-2017-Group-Photo

December 5, 2017

GROW Summit 2017 Tackles Marketing and Business Managem…

This year’s think-tank style event brought together leaders from across the green industry to deliberate on topics such as disruptive marketing, cost accounting, and Millennials, to name a few.

Read More

December 5, 2017

Skagit Horticulture Builds New, Inclusive Business With…

By merging two large-scale producers, Skagit Gardens and Northwest Horticulture, the new company has realized its strengths through focused divisions that emphasize efficiency and success.

Read More
Young-Grower

December 4, 2017

New Report Shows Older Growers Outnumber Younger Grower…

A survey conducted earlier this year by the National Young Farmers Coalition highlights the far-reaching set of challenges faced by today’s young growers, including rising debt and a struggle to find quality employees.

Read More

December 4, 2017

Raker-Roberta’s Young Plants Debuts as Roberta’s Finali…

On December 1, Eric Wallien of Roberta’s Inc. in Waldron, IN, officially purchased C. Raker & Sons in Litchfield, MI. The new identity of the company is now Raker-Roberta’s Young Plants, according to a Dec. 1 letter to Raker’s customers, suppliers, and business partners from Vice President Susie Raker-Zimmerman. “There have been minimal changes in management and we will be providing the same products and services on which we have built our reputation in the industry,” Raker-Zimmerman said in the letter, which also announced the name change and new logo. The sale of C. Raker & Sons was announced in September . A series of events affecting Raker’s financial situation caused the need for the operation to find an alternate solution. Roberta’s had been a customer of Raker’s since 2011, and the fourth generation, family owned grower-retailer was a fan of Raker’s commitment to quality. The agreement to purchase C. […]

Read More
Low-Cost-Build-Your-Own-Irrigation-Sensors-feature

December 4, 2017

Nine Things You Need to Know About Irrigation Sensors

Knowing the amount of water in your soil can help you better manage irrigation, leading to water savings and a stronger bottom line.

Read More
Brandon-Coker-and-John-Ruter-University-of-Georgia

December 3, 2017

Great Plants for 2018 That Stand Up to Heat and Humidit…

In his latest column, Allan Armitage credits trial managers at the University of Georgia, who have come up with an extensive list of plants that continually outperform others throughout the season.

Read More