Three million acres of irrigated land in Colorado could be an untapped source of hydropower and a revenue source for irrigation companies.
A Colorado State University engineering professor is collaborating with an engineering firm, Applegate Group Inc., to review the potential power that could be generated by “low-head” turbines in irrigation canals.
Lindsay George, water resource engineer in the Glenwood Springs offices of Applegate, and Dan Zimmerle, a research scientist and adjunct mechanical engineering professor at Colorado State, received a $50,000 grant this year from the Colorado Department of Agriculture to study canals in Colorado. The grant is part of the Advancing Colorado’s Renewable Energy (ACRE) Program to promote energy-related projects beneficial to Colorado’s agriculture industry.
Water in irrigation canals moves fast enough to produce anywhere from 100 kilowatts to two megawatts of power. Two megawatts of power is enough energy to supply power to about 850 typical homes.
In the study, the researchers are examining turbines that could generate power from an elevation drop in an irrigation channel of five feet to 30 feet such as water diversion structures or chutes. They’re also investigating how to connect that power to the traditional electric grid.
Zimmerle and George are now conducting an inventory of irrigation canals in Colorado and surveying roughly 250 ditch companies and individual ditch operators around the state. The survey is available to ditch operators at http://www.applegategroup.com/news/low-head-hydropower-survey-available.
Zimmerle will speak about the project on Feb. 16 in Berthoud at a full-day workshop, “Low Head Hydroelectric Opportunities for Ditch and Reservoir Companies,” sponsored by the Ditch and Reservoir Company Alliance. DARCA is a resource for networking, information exchange and advocacy among mutual ditch and reservoir companies throughout Colorado.
“DARCA is very much interested in projects that will enhance the financial viability of its member ditch companies,” Executive Director John McKenzie said. “The introduction of these types of distributed power projects will help develop additional revenue streams for Colorado ditch companies.”
“That type of infrastructure allows for the potential of low-head hydropower,” Zimmerle said. “There are extensive irrigation systems in Colorado, so we’re identifying where hydropower could be applied in those irrigation channels.
“A large part of the cost for small generating plants is the cost of running a distribution line to generating plants,” he said. “There are good places in the irrigation system that will generate significant amounts of power. But we need to explore this issue with utilities – the approval process, interconnection standards and potential revenue.”
Hydropower generated from irrigation ditches is known as low-head hydropower or hydrokinetic power – what the Federal Energy Regulatory Commission (FERC) defines as projects that “generate electricity from waves or directly from the flow of water in ocean currents, tides or inland waterways.”
Interest is growing in that type of power because technology is improving, George said: “FERC has a Memorandum of Understanding with the state of Colorado to streamline the permitting process for low-impact hydropower projects in existing canals.
“Hydrokinetic turbines produce a small amount of power and are going to be practical in certain situations,” she said. “With our study, we expect to report a total amount of power that could be produced using low-head and hydrokinetic turbines in our irrigation canals that should help irrigation districts in planning their projects.
“New low-head technologies have potential at sites previously considered unfeasible for hydro development because of a lack of significant elevation drop,” George said. “Irrigation canal drop and check structures, as well as existing diversion dams and outflows, may provide the drop necessary to implement these new low-head hydro technologies.”
Applegate Group, with offices in Denver and Glenwood Springs, is an engineering and consulting firm with expertise in water planning, water rights engineering, water policy and development of water infrastructure.