Temperature control panel at a factory. Original public domain image from Flickr
ft. facility that features energy efficient glass roof with curtains that block or trap heat, radiant heaters in or above the floor, and the replacement of an oil-fired hot-air furnaces with propane fueled boilers that supply fin-tube and cement embedded tube elements with hot water. With current fuel prices, there is a projected 2011 energy cost savings of more than $20,000; a 40% reduction in energy costs – exceeding projected savings. Plant health and quality has improved and been more consistent because the temperature and humidity is computer controlled and distributed evenly throughout the facility. Utilizing sensors and a roof mounted weather station the system can maintain four different climate zones 24-hours a day. Two 1,000,000 BTU propane fueled boilers heat the water to 190 degrees for the 8,000 feet of fin-tube heating elements were used where the original foundation, and the 8,000 feet of tubing that was embedded in a new cement foundation. After traveling through the energy efficient system, water only looses 20 degrees. When temperatures become to hot, motorized roof vents open to allow rising heat to escape; a 98% energy savings from massive fans that previously forced air out. Both systems create a microclimate in and round the plant trays in the growing and sales room. Representing Good Harvest Farm Chris Powell says, “You don’t need to have a lot of land to have a lot of green houses. There are places in cities where vegetables are grow on store roof tops and selling them below in the same structure.” USDA Photo by Lance Cheung.