Sustainable Year-Round Growing in High Tunnels Utilizing Waste Vegetable Oil in Conjunction with a Subterranean Geothermal and Solar Heating and Cooling System
A furnace purchased from Clean Burn was installed for the comparison studies of heating a High Tunnel with and without a Subterranean Geothermal and Solar Heating and Cooling System (SGSHCS). The furnace was installed in a used walk-in cooler and ducted directly into the High Tunnel with the figs. The furnace was run on filtered waste cooking oil from local restaurants. The second High Tunnel was equipped with the SGSHCS and was tested simultaneously side by side with the first High Tunnel. The SGSHCS High Tunnel was also equipped with a furnace to be used at the coldest temperatures outside of O degrees F. The results were amazingly good. The temperature difference was only 4-5 degrees between the High Tunnel heated with oil and the Tunnel with the SGSHCS system while the temperature outside was 0 degrees F.
The grant funds were used to purchase and install a 175,000 BTU/h CleanBurn furnace as well as to pay for the waste oil supply and delivery, blue foam insulation around the perimeter of the Tunnel and polycarbonate end walls for better insulation and stability of the High Tunnel to high winds and storms. Clean Burn Inc. has shown great interest in the research with the SGSHCS system and has generously provided a brand new Furnace 250,000 BTU/h (~ $6000 retail price) for the testing and experimentation. The new furnace is in the process of installation in conjunction with the SGSHCS system of the new High Tunnel.
2007 Expenses for the project:
1. Mechanical Systems
175,000 BTU CleanBurn Furnace 4,200
2. Mechanical Systems
Installation of Furnace, Materials
and Supplies 2,585.46
3. George Springer
waste cooking oil supply and delivery 500.00
4. Morgan County Seed
Polycarbonate, J and H channels for end walls of High Tunnel. 2,157.71
5. Pacific lumber
Lumber for end walls and baseboards 669.92
6. Midwest Econo Sales
Nozel for oil furnace 44.86
Tape for polycarbonate end walls 24.38
8. Mechanical Systems
Parts for furnace 211.90
The test results with the SGSHCS were so good that it could be used alone without the heating furnace for growing figs, except only for a back up for extremely cold subzero temperatures. The small difference in temperatures of the Tunnel heated with oil and the one with SGSHCS at 0 degrees F outside means that the SGSHCS system can provide the equivalent energy of a 175,000 BTU/h furnace without using any oil. The lowest temperature of the air coming from the ground below was 48 degrees F and is usually between 50 and 55 degrees F. On sunny winter days the system recharges and the temperature can go up to 60 degrees F. Since it takes ~ 1500 to 2500 gallons of waste cooking oil for a winter season to keep a High Tunnel warm and above freezing at night and on cold winter days, the use of a furnace coupled with the SGSHCS will save a lot of oil and allow the system to achieve higher temperatures at much lower cost.
The hot air from the furnace comes out at temperature above 120 F and a beneficial use of the furnace is the possibility to heat smaller compartments within the High Tunnel at elevated temperatures, while keeping other areas at normal or lower temperatures by passing the hot air duct under a row cover. I used this successfully to start my seeds and grow transplants for further planting.
WORK PLAN FOR 2008
Complete the installation of the second CleanBurn Furnace generously provided by CleanBurn for research and testing on the new SGSHCS system. Generate all data measurements for the performance of the furnace in conjunction with SGSHCS. Grow year-round utilizing the solar and geothermal energy more efficiently.
Organize field trips, presentations at meetings, publications and interviews regarding the new alternative Geo-Solar energy system.
Initiate research on new applications for growing with the new system with particular emphasis on growing algae for bio-fuels. (See 2007 Grant project, FNC07-680, Sustainable Growing of Algae in High Tunnels for Bio Fuel for details).
I had the wonderful opportunity to be invited by Dr. Ted Carey, Extension Specialist Food Crops, Kansas State University as a plenary speaker at the Great Plains Vegetable Growers Meeting in 2007 in St. Joseph, MO. The presentation allowed me to present my ideas about using alternative energies for growing in High Tunnels and for growing figs in particular. The presentation covered the use of automatic curtain control powered by a solar panel, the Subterranean Geothermal and Solar Heating and Cooling System and the Clean Burn’s automated waste cooking oil-heating system.
The successful growing of figs in the High Tunnels has excited many growers and several have already started growing them in High Tunnels on their farms. I have provided them with detailed instructions on the aspects of growing the figs and the technical knowledge for operating the systems. I even supplied them with rooted fig plants ready for planting in their High Tunnels. Several groups of interested farmers, specialists and researchers visited the operation during the summer of 2007. Among them was a group of five from the Missouri State University, State Fruit Experiment Station with Patrick Byers, Fruit grower advisor and Marilyn Odneel; the State Vegetable Crops Specialist from the University of Missouri, Columbia Dr. Lewis Jett; 12 people from the St. Louis Botanical garden Club, many individual local farmers, neighbors and friends. Another group of 20-30 growers, members of the University Growers association from Columbia, Missouri with Dr. James Quinn, the Regional Horticultural Specialist for the University of MO, Columbia is scheduled to visit on a Field trip on April 22, 2008.
Another way to provide information on the project was the participation in the High Tunnel on-line communication and discussion. A website will be posted for wide access availability for all members.
Last but not least important was the opportunity to provide fresh figs to local restaurants and two green markets twice a week from early summer to late fall. It was the most rewarding experience I have had to be able to bring this delicious fruit to the people in St. Louis months before and after they were available from California or other warmer but more distant places. People simply could not believe that these ripe and wonderful figs were locally grown for them and many were trying this fruit for the first time in their life.