SAN DIEGO, CA. The term “pressure” has been tossed around a lot in the farming industry and one thing is clear. We all agree pressure is bad. At worst, it is a disaster, at best, a distraction. But not in this case. There’s a fresh positive attraction to pressure when it comes to David Chelf and his amazing positive pressure greenhouses. We caught up with David last October in San Diego for an interview. Within 20 minutes we knew we had to share this story about a revolutionary physicist-turned-farmer with patents in 13 countries and a very busy schedule. For you venture capitalists out there, take note of Airstream Innovations, Inc.
Imagine a translucent tent the size of a football field held up by nothing but air. The enormous cover is firmly attached at the base by a heavy-duty sleeve buried into the ground. At one end are two 20 foot cylindrical intake towers protruding through the roof. At the other end is a roll-up door big enough to drive a tractor through. Outside, the towers are wrapped in pleated skirts that act as 360 degree checkvalves forcing the prevailing wind inside. At the juncture of the intake tower and the cover are adjustable-speed fans that keep the structure continually inflated. Inside, at the base of the intake towers, a high-quality net prevents pests from entering.
The environment is fully automated through a programmable control box that calibrates the wind and fan speed to stabilize the tunnel while a network of cables are secured criss-cross fashion over the entire structure to equalize the air pressure on the cover. Chelf seems to have thought of everything including dedicated generators, a battery backup system, and an early storm-warning system to protect staff and the crop in case of an emergency. Airstream has rated their greenhouses to withstand winds up to 80 miles an hour.
Chelf admits he did not invent ventilation or air supported structures. What is ground-breaking is his ability to increase productivity by precisely controlling the airflow to optimize growth conditions. Airstream greenhouses can be programmed to deliver the perfect ventilation scientifically calculated for optimal transpiration and crop mineralization for virtually any crop. The result is an astounding 30% more growth than conventional greenhouses.
“I knew nothing could grow without airflow,” found Chelf explains. “And I thought if I could work with natural forces, like the wind, maybe I could create a structure that held itself up with very little energy.”
Chelf has been developing his technology over 10 years. A former UCLA PhD candidate in physics, Chelf left the program to do what he loves: grow healthy, high-quality and exceptionally tasty food. He became expert in commercially growing mâche, an edible green, for Trader Joes and soon became convinced a controlled environment was what was needed. Like a modern-day Edison, Chelf refined his greenhouse production system, dialing in every aspect imaginable. His first tunnels were for his own label growing mara de bois strawberries and heirloom tomatoes for high-end restaurants. Three years ago, through word-of-mouth, the citrus nurserymen came calling and after several successful commercial installs, Chelf decided to focus all his efforts on selling his greenhouses.
And selling they are. Airstream Innovations has found great demand within California’s citrus nursery production. The USDA and CDFA are regulating California citrus nurseries due to the presence of a flying insect, the Asian Citrus Psyllid (ACP), and the disease they may carry, Huanglongbing (HLB). Because of their insect netted intakes and the high positive pressure throughout, Airstream greenhouses easily meet the requirements of the USDA for insect protected production of citrus seedlings.
Because these are not rigid structures, adopters are saving as much as one-half to two-thirds the expense of a conventional half-acre greenhouse. Installation takes five workers two weeks to trench, erect the towers and attach the cover. Then in just a few short minutes, your greenhouse is inflated to full capacity and workers and equipment can immediately move in. The low cost of entry, optimized growing conditions, water efficiency, and the elimination of pesticides, leads to a rapid return on investment in as little as one year.
A less-apparent benefit is that Airstream’s structures are considered temporary so property taxes may not apply. This is a significant benefit to property owners looking to make their land productive but avoid the permits and costs associated with a rigid, permanent structure. To date, Airstream has delivered 18 units with four more scheduled for installation. They estimate a million square feet will be in full production before year end.
As we ended our interview we learned citrus nurseries are in dire need of an affordable controlled environment and Airstream Innovations’ greenhouses appear to be the best thing going. We also learned smaller organic growers can obtain a huge market advantage of a pesticide-free half-acre for as little as $125,000. But that was not all. In the following months since then, we visited their three tunnels at Brokaw Nursery in Ventura County. It was beautiful inside, almost ante deluvian. But what really hit us was just how big these structures really are. Now, we imagine other uses like indoor winter parks, housing for animals, fish farming, organic herb farms, year-round polo and soccer fields, concerts, weddings and more. As there appears no limit to the possibilities, this is a company worth keeping an eye on.