>On Oct 7, 2008, at 8:05 AM, Patricia Haines wrote: > > > does anyone locally use the heat generated by decomposing wood chips > > for greenhouse and/or cold frame heat?
Patricia--There are, or were, a couple of farmers in the area that have used compost to heat greenhouses. However, you can't use wood chips alone. Wood is very high in carbon and decomposes only very slowly by itself. The usual procedure is to mix large animal manure (cow, horse) about 50-50 with the wood chips, giving a better balance of carbon and nitrogen. When this composting mixture enters the thermophilic mode it yields the heat used for greenhouses, hot water, etc., al a' Jean Pain. One commonly used technique is to mass the composting mixture on the exterior walls of the greenhouse, up to about 4-5 feet above the ground, and then circulate air through the compost pile into the greenhouse. A system of perforated pipes is imbedded within the compost feeding air through the pile, where it is heated and fed into the greenhouse. Sometimes this is a "gravity fed" system, essentially using convection, and sometimes small fans are used to move the air through the pile and into the greenhouse. I have also seen a system wherein long, thick beds of composting material were directly sown with plants in the green house. The heat from the compost kept the roots and the plants above from freezing. This system wasn't as effective as the first system mentioned above and only works well with cold weather plants that are usually grown in cold frames--kale, etc. I think it would be feasible to make hot water with a properly constructed, sufficiently massive compost pile and use the hot water to heat a greenhouse or system of cold frames. I suppose there are other possible arrangements given the materials at hand and the quantity of thermophilic compost available. I would be very interested in hearing of your progress on any projects developed at Level Green Institute. Take care. Tom ****************************************** Tom Shelley 118 E. Court St. Ithaca, NY 14850 607 342-0864 [EMAIL PROTECTED] Compost Educator and Sustainability Scion* What Does Zero Waste Mean? "If it cant be reduced, reused, repaired, rebuilt, refurbished, refinished, resold, recycled, or composted, then it should be restricted, redesigned, or removed from production." Berkeley Zero Waste Resolution See http://www.cityofberkeley.info/council8/newsletter.pdf *noun: a shoot or bud of a plant, esp. one for planting or grafting _______________________________________________ For more information about sustainability in the Tompkins County area, please visit: http://www.sustainabletompkins.org/ RSS, archives, subscription & listserv information for: [email protected] http://lists.mutualaid.org/mailman/listinfo/sustainabletompkins free hosting by http://www.mutualaid.org
