Directing Radiant Heat
Going hydronic has saved Urban Growers more than 40 percent on its energy bills.
August 10, 2011
At Urban Growers LLC, in Burton, Ohio, installing a hydronic heating system from Delta T Solutions has saved owner John Urbanowicz between 40 and 50 percent annually on energy bills, compared to the costs of forced air heating.
As a young entrepreneur who started the business on his family farm in 1999 while working full-time for BFG Supply, Urbanowicz has always been progressive. Realizing the inefficiencies of forced air in his 95,000-square-foot wholesale and retail operation in northeastern Ohio - an area prone to long, cold winters that can cause significant heating challenges - Urbanowicz began working to develop a customized system.
"I first started to upgrade my heating system about 10 years ago, when I realized that the forced air overhead heaters were not as efficient as I liked," Urbanowicz says. "I had seen a lot of greenhouse operations and I knew what I wanted. I worked with Delta T Solutions, which helped me figure out what we needed to fit our size and growing zones."
A Custom Fit
Urban Growers' heating system includes an RBI natural gas boiler, a TF2 under-bench rubber tubing system, and an in-floor hydronic system, embedded in the operation's concrete floors.
"We added thin pipe under benches, then heat retention curtains, then in-floor heating," Urbanowicz recalls. "The natural gas boiler controls four different zones covering 30,000 square feet. As we learned to adjust each zone, we found that it took less growing time because we had the heat where the plants need it. Our plants were healthier and we could speed up our crop times by as much as three weeks."
Radiant Heat In Action
Hydronic heating is the use of water as a heat-transfer medium in heating systems, using a boiler to heat water and a pump to circulate the hot water in rubber tubes that are either buried underground for field growing, embedded in concrete for radiant floor heating or installed in greenhouse bench systems. Separated radiant heat zones are controlled by one thermostat and served by a manifold, which distributes the flow of hot water to the individual circuits of tubing within each zone.
The process works through thermal radiation, which travels in invisible waves through empty space. Radiant heat is absorbed by the objects in its path, rather than in the air. It uses heat transfer, along with a superior conductor of heat in the form of a liquid, versus forced air, which relies solely on convection and air. The result is a consistent, comfortable temperature that makes the greenhouse feel warmer at lower air temperatures than are required with conventional heating systems.
A Word To The Wise
"We're neither a large nor small grower and not exactly state-of-the-art," Urbanowicz explains. "But if you want to have a long-term business, it's important to think about and understand your heating costs. You need to know how you heat your crops and realize that to grow good quality plants and be efficient, you need to make an investment in the right heating system."
For more information about Urban Growers, visit Urban-Growers.com.