On Thursday, April 13, Colorado legislators will hear why Colorado should study the link between solar energy and water. Known as this still-emerging practice, hydropower involves placing solar panels over canals and other bodies of water.

Proponents say the marriage could save water by reducing evaporative losses while increasing the amount of power solar panels produce.

The proposal is part of the bill, SB23-092it will be heard by the Senate Transportation and Energy Committee.

The bill also proposes to boost the development of agrivoltas, where solar power is generated simultaneously with agricultural production. A similar agricultural bill was introduced last year but did not pass. Aquavoltaics are new to the bill this year.

Senator Chris Hansen of Denver, the primary sponsor of both bills, said after examining water conservation efforts around the world, hydropower is one of the most lucrative ways to reduce evaporation from canals and reservoirs. said to have discovered that Doing this with solar panels creates “a huge number of multiple streams of value,” he says.

Covering the water can reduce evaporation by 5% to 10%, while cooling the water increases the power generation efficiency of the solar panel by 5% to 10%. Electricity can be used to cover the cost of pumping water.

Solar panels in cooler climates produce power more efficiently. That’s why solar developers are so keen on the potential of Colorado’s San Luis Valley. At over 7,000 feet in elevation, this canyon is at a much cooler height than the Arizona desert, but with about the same amount of sunshine.

Colorado has already restricted the deployment of Aqua Volta. In 2018, Walden became the first community in the state to deploy solar panels over small ponds used in conjunction with water treatment. 208 panels provide about half of the power required to run the plant. The town of 600 people, located at an elevation of 8,100 feet in North Park, covered half of the $400,000 cost, with the rest covered by state grants.

Other water and wastewater treatment facilities, such as Fort Collins, Boulder, and Steamboat Springs, also employ renewable power generation, but not necessarily on the water like hydropower.

As introduced, the bill authorizes the Colorado Water Conservation Commission to “fund projects to study the feasibility of using aqua volta.”

Hansen said he sees great potential in Colorado for placing floating solar panels on reservoirs and above irrigation canals. “The Denver Reservoir alone has a huge opportunity,” he said. “Add a few more canals across the state and you have hundreds of megawatts of opportunity here,” he said.

Other Western countries are also eyeing the technology.

Arizona’s Gila River Indian community announced last year that it was constructing a pilot project to cover a canal south of Phoenix with the help of US Amy Corporation engineers. “This project provides an example of new technology that will help the Southwest cope with its worst drought in more than 1,200 years,” said Tribal Governor Stephen Rolleis.

When completed, it will be the first solar project in the United States to cover a canal.

But there are precedents in India for both Gila and a $20 million pilot project launched this year by the Turlock Irrigation District in California.

The Republic of Arizona reports that officials at the Central Arizona Project (CAP), a major user of the Colorado River’s water and Arizona’s largest consumer of electricity, are scrutinizing pilot projects in Arizona and California. will be tracked to In the past, both CAP and his Salt River project, one of Arizona’s two largest water suppliers, have cited hydroelectric engineering challenges.

The new Colorado bill also authorizes the Colorado Department of Agriculture, Drought and Climate Resilience to award grants to new or ongoing demonstration or research projects that demonstrate or study agricultural uses. This is overseen by a stakeholder group.

Mike Kruger, chief executive of the Colorado Solar and Storage Association, said his members would like to see the broadest possible definition of eligible projects. “I don’t think it’s going to be an ‘amber wave’ under the panels. It will most likely be cattle or sheep grazing,” he says.

That’s exactly what’s happening near the Delta. There, a solar power project was proposed near the substation for the purpose of serving the Delta Montrose Electrical Association. Neighbors objected, and the county board rejected it with his two-to-one vote. The project developer is back with a modified project that calls for sheep to graze in solar panels. This revised proposal passed by a 3-0 vote.

Hansen says this is exactly the model he hopes will play out in the competition between land for agriculture and land for renewable power generation.

“What is clear is that county commissions don’t want a battle between solar and agriculture,” says Hansen. He cites the Delta County incident as a prime example.

“When you combine that with grazing, we would say yes, and that is exactly what the Delta County Commissioner did. I am thinking.”

Allen Best is a frequent contributor to Fresh Water News. He also publishes his Big Pivots, an electronic journal documenting energy and water changes in Colorado and beyond.