Part of a new U.S. Department of Energy grant for innovative geothermal technology is going to fund a project that could help small towns and mid-sized cities generate low cost local power, cut their carbon footprint, create new green jobs, and even develop local sources for fish and produce. The technology is called “cascading” geothermal because it uses and re-uses the same fluid in a series of applications.
Cascading Geothermal Technology
Oddly enough a religious community called I’SOT (yes, that I’SOT) in Canby, California provides a textbook example of a cascading geothermal project, which is under development in partnership with the Department of Energy and the National Renewable Energy Laboratory. In 2006 the community began operating a geothermal heating system that provided heat and heat and hot water for 34 buildings, but the effluent from that operation was simply filtered and discharged to a river. Under the new project, the highest-temperature fluid will be used to generate electricity. After that, energy can still be extracted for additional space heating and hot water, operating up to ten acres of greenhouses, heating up to four 30-foot diameter aquaculture tanks, and for melting snow. The system may also provide enough energy to operate a new food storage and laundry facility.
Geothermal for Small Communities
The Modoc Contracting Company – also of Canby – won the DOE grant, receiving $2 million out of a larger $20 million grant for job-creating, innovative geothermal technology that was shared among six other projects. That $2 million is a modest amount compared to the impact it could have on communities across the U.S., as DOE estimates that in the west alone there are about 1,500 possible well sites in small towns and mid-sized cities with the potential to develop cascading geothermal projects. That in turn could create new green jobs in local aquaculture and greenhouse-based agriculture operations.
Cascading Geothermal for Big Cities
If the concept of urban fish-farming seems a little far fetched, at least one expert has been successfully raising food grade fish in the middle of New York City, so cascading geothermal projects may have potential in larger cities where space is hard to come by. The possibility of developing add-ons and tie-ins with other forms of renewable energy could also help maximize the use of space. For example, a greenhouse operation powered by geothermal energy could converge with algae biofuel production, and an aquaculture pond could double as a platform for a floating solar energy installation.
Image: Small town by jk+too on flickr.com.