New law set to open door to more hydroelectric power from irrigation
With the greatest concentration of suitable irrigation canals in the state, farmers in Delta County are poised to take advantage of a new Colorado law that streamlines the installation of hydroelectric power generating stations, state officials said.
Farmers in Mesa and Montrose counties are also eyeing the feasibility of building small hydro plants to make their own electricity, officials said.
The new law makes it easier for farmers to cut electricity costs by generating their own power from energy stored in canals and waterways used to irrigate crops, the Colorado Department of Agriculture reported.
Total savings could amount to tens of thousands of dollars a year depending on the size of the farm and the amount of power it generates, said Kurt Johnson of Telluride Energy, a consultant involved in creating a study of the state’s hydroelectric potential.
In basic terms, hydro power works like this: Intake from a water supply — which may be a river, irrigation ditch or pipeline — brings water into a powerhouse that houses a turbine and a generator. Water from the intake turns the turbine, causing the generator to create electricity that is carried by a power-line to where it is needed.
Under the new law, on-farm hydroelectric plants not tied to the grid that generate power solely for farm operations will avoid most state and federal permitting processes normally required for power generating plants, Johnson said.
The new law also allows state and federal permitting processes to run simultaneously, raising expectations that the entire process can now be completed in 60 days or less, he said.
The state study identified nine of 77 drop sites in Delta County suitable for small hydro plants. The nine have a combined capacity of roughly 0.8 megawatts and would generate approximately 4 gigawatts per year, said Lindsay George of Applegate Group, another consultant involved in the study.
Small hydro plants range in size dramatically, from 20 kilowatts up to 345 kilowatts. Costs range from about $160,000 to almost $1 million to build, George said.
The owner of Bear River Ranch near Steamboat Springs, for example, installed a hydro-mechanical system to power the ranch’s center-pivot irrigation system.
“The system uses the power of falling water to directly drive and pressurize the center pivot, eliminating the need for electricity and significantly reducing operating expenses,” according to the state study.
The 5.2 kilowatt turbines installed at the ranch in 2012 use 560 gallons per minute to produce power to drive a center pivot’s hydraulic pump, the study said.
The $13,000 project was funded through $6,000 in support from the U.S. Natural Resources Conservation Service, yielding out-of-pocket costs to the ranch of $7,000 and an expected 100 percent return on investment in slightly more than three years.
“This shows that you really need just the right combination of factors to make a ditch drop site work,” George said.
Factors include the flow available, how much time during the year water is available, the elevation drop, the distance to the nearest power-line and the cost of a turbine.
The amount of energy that can be produced by water depends on two factors:
■ How much water flows;
■ The rate of drop, or change in elevation;
“You really need to have both,” George said. “If you just have water flowing by very slowly, there is not much energy contained in that water. But if the water is falling or pressurized through a pipe, this creates a significant amount of energy.”
Irrigation and its associated electricity costs are one of the largest areas of energy consumption. Colorado farmers report spending an average of about $33,000 per year on electricity, while spending an average of $16,000 on diesel and about $8,000 on gasoline, according to the state study.
Electricity costs to power irrigation pumps typically make up more than 50 percent of total electricity expenses. In 2008, for example, electricity expenses for the entire Colorado agriculture sector were estimated to be $137 million, the study said.
Currently, wholesale electricity prices are relatively low, so the most economically attractive agricultural hydro development opportunities are for net-metered, small projects based on pressurized irrigation pipelines where new hydro installations can help Colorado agricultural producers lower energy costs by offsetting purchases of grid electricity at a full retail rate, George said.
The key to success of a new agricultural hydropower program will be availability of federal funding, which can typically pay for 75 percent of center pivot construction cost, in an amount up to $300,000, Johnson said.
Center pivots are typically driven by either grid-electricity or diesel generation. The incremental cost of installing center pivot hydro-mechanical equipment is typically about $15,000, and adding conventional hydro typically costs between $25,000 and $50,0000, “a small amount relative to overall typical center pivot installation costs,” he said.