Colorado Examines Hydropower in Irrigation Ditches

Researchers in Colorado are investigating the potential for the state’s irrigation canals to be used as a source of renewable hydropower.

Engineering firm Applegate Group Inc. and Colorado State University have received a $50,000 grant from the Colorado Department of Agriculture to look into generating hydropower from the 3 million acres of irrigated land in the state. The grant is part of the Advancing Colorado's Renewable Energy Program to promote energy-related projects beneficial to Colorado's agriculture industry.

Hydropower is created by running water through a hydraulic turbine that spins and drives a generator shaft to create electricity. Most small hydro projects, also called micro-hydro, divert a portion of a river or creek’s flow, or are constructed on established channels, such as irrigation ditches.

Currently about 10 percent of U.S. electricity comes from hydropower, according to the Colorado Renewable Energy Society. Compared to other renewable energy sources, hydropower is known for being consistent and durable.

Recent technological advancements in small hydro — the development of hydroelectric power on a scale serving a small community — have made Colorado irrigation canals a likely possibility for hydro development, said Colorado State University professor Daniel Zimmerle, who received the grant.

“In the small hydro area, [Colorado has] a good chance of being a leader because we have a lot of state and local support for the idea,” Zimmerle said. “It helps to be in mountains.”

Zimmerle and researchers will study how efficient and plausible low-head hydropower, which uses river current and tidal flows to produce energy without the use of a dam, is in hundreds of statewide irrigation ditches with drops between five feet and 30 feet.

The costs and environmental impacts of constructing a dam make traditional hydroelectric projects difficult. However, small hydro costs are similar to other renewable energy sources, Zimmerle said.

In terms of wiring the hydro facility to be managed remotely and connected to the electric grid, all conversion inverters and communications equipment that have been used for other applications will be reapplied to small hydro, he said.

“Once you get those big rocks in place, there are actually quite a few questions about economic viability and how you implement these systems,” said Zimmerle. “That’s where we are going to go after this research project is over.”

Until recently, “tortuous” government permitting processes, along with the large initial cost of the systems, have been the biggest barriers to implementing hydro technology, said Zimmerle. Plus, water resources can be particularly troublesome in terms of water rights issues and flow rates, he added.

However, as barriers to renewable energy sources have been knocked down over the past decade, more opportunity for micro-hydro has also become available, he said, and legislators have been green energy promoters.

Small hydro technology may also prove to be a revenue source for irrigation companies, researchers said.