If the midwest is America's breadbox, California is its orchard. The Golden State produces nearly half of America's fruits, vegetables and nuts—more than 400 varieties—an output valued at more than $43.5 billion each year. But the energy needed to grow, harvest, process, and ship this bounty is no small sum. That's why one ingenious farmer is powering his operation using already produced shell waste to zero out his electric bill.
Walnuts, like those grown on Russ Lester's Dixon Ridge Farms in Winters, California, are some of agriculture's most energy-intensive crops given the amount of product you get from them. The inedible shell constitutes 50 to 60 percent of each nut, and has conventionally just been discarded. On Dixon Ridge's 400 acres, that translates into about 2.5 million pounds (more than 1200 tons) of shell waste annually. But rather than pay someone to dispose of these shells, Lester instead converts them into syngas using a cadre of downdraft gasifiers built by the Community Power Corporation of Englewood, CO.
Known as the BioMax, these machines can transmogrify a variety of woody biomass, and even some plastics, into nitrogen-diluted syngas. This includes everything from wood chips and pellets to orange and grape skins, cardboard and product packaging to kitchen waste and plastic utensils. Anything with less than 25 percent moisture can undergo gasification.