3 Reasons Growers Love Floor Heat
by Michael Kovalycsik, National Sales & Marketing Director, Delta T Solutions
Winter days are short but the nights are long, and when those long, cold nights begin, it’s not just the temperature that drops. If you don’t have an efficient, sustainable heating solution to heat your greenhouse operation, your profits suffer — and so could your crops.
With a conventional, forced air heating system, heat rises, so crops grown on the ground often suffer cooler temperatures than those grown on benches. Plus, heat from conventional sources is known to escape through the greenhouse roof, which is essentially equivalent to throwing money out the window.
Conversely, in-floor radiant heating using hydronic or hot water heat systems efficiently heats the greenhouse from the floor up, keeping the heat close to plant roots, which in turn improves plant health for more established roots and uniform crops.
THE PROOF IS IN THE CONCRETE
1. Improves plant health. In-floor radiant heating systems heat the greenhouse from the floor up, controlling the soil temperature, which ultimately accelerates rooting and plant growth.
Delta T Solutions’ high density (HD) system delivers hydronic heat through a grid of high quality polyethylene tubing installed in the concrete. Using the concrete floor as a radiant surface, heat rises from the floor into the greenhouse and directly to the plants. The direct contact of the root zone with the warm floor provides for maximum soil and plant temperature control, resulting in even temperatures and even crop growth.
In-floor radiant systems like Delta T Solutions’ DELTA-TUBE™ EPDM LD rubber tube in-ground (sand, soil or gravel) heating excel for general growing, rooting of cuttings and seed germination in starter houses. Growers who use radiant floor heating systems to warm soil or nutrient bags for growing greenhouse produce like tomatoes and cucumbers have shown a 50 percent increase in yield. Grape growers have found a quicker and even more callusing pattern by using bottom heat to callus grape stock.
Pam Snodgrass, President, P&D Nursery, Tualatin, OR, says she has found Delta T Solutions’ LD system to heat twice as fast as air heat, and that the extent of the plant health and quality benefits was surprising.
“I knew I would grow a better crop and that it would be energy efficient, but I didn’t realize how much better of a crop it would be,” she says. “Plants don’t seem to stretch as much because they are getting heat from the roots, which form faster and better, making a sturdier plant on top.”
2. Improves the growing environment. Radiant heat allows growers to more efficiently and effectively heat the growing environment by controlling soil and water temperatures for different crop needs. Heat rising from pipes embedded in the ground warms the greenhouse starting at the soil level, and maintains a constant feeling of warmth throughout the structure.
Optimum soil and plant temperature control combine with the ability to create different temperature zones for growing flexibility. Snodgrass says the LD system allows her more control over the entire greenhouse climate, so she can heat certain areas of it year-round.
“We have it zoned so if we only have a crop in one zone, we only have heat there and don’t have to heat the whole house. We zone it off, curtain it off, and can have a mix of different crops in there, with different climate needs, too.”
Another advantage of hydronic systems is the flexibility of the fuel source, with options for using gas, oil, electricity, and even solar and geothermal energy, increasing grower flexibility.
3. Fuel efficient. Hydronic radiant heating uses a closed loop system that loses little heat while moving heated water to its destination. Requiring very little electricity to run, hydronic heating is ideal for growing operations in areas with high electric fees.
Additionally, growers who use in-ground heating systems have shown a 30% reduction of fuel usage, along with shorter production times and superior product quality, for better overall energy-efficient production.
Eric Nelson, owner of Neosho Gardens in Council Grove, KS, says he has experienced fewer problems since he installed five acres of in-floor radiant heating systems, compared to his old forced air systems, because of the number of unit heaters that were necessary to keep the greenhouses warm.
“With hydronic heat, it's always warmer,” he says. “The systems don't break down and we have seen significant energy savings and overall cost savings. Our system did cost a lot of money up front but in the end, it pays off with better efficiency, using less BTUs than forced air.”
27711 Diaz Rd, Suite B, Temecula, CA 92590 • 800.552.5058 • 760.682.0428 (fax) • www.deltatsolutions.com