Small-scale hydropower generators installed in irrigation canals

Emily Morris, CEO and founder of Emrgy, said her inspiration for making electricity in places that some people might find unlikely was seeing water swiftly flowing through the vast network of U.S. irrigation infrastructure. The U.S. Bureau of Reclamation alone operates 1,600 miles of main canals.

In the same way that putting solar on rooftops avoids disturbing the land, making use of existing canals means the hydropower turbines don't have to disturb the natural environment.

"Our infrastructure represents a new sector of renewable energy real estate," Morris said in an interview.

Irrigation canals in the U.S. are made of concrete or stone and transport water from main sources to fields. Emrgy units look something like a propeller with blades rotating parallel to the ground. Water in the canals turns them and then flows past; there is no dam. The spinning turbines do change how the water moves through the canals, slowing it, so Emrgy works closely with water operators.

Emrgy's installations are very small in the commercial sense — between 2 and 10 megawatts. But that's approximately enough to power a neighborhood or a small campus.

It "can amount to a pretty significant amount of power," said John Gulliver, an engineering professor emeritus at the University of Minnesota, given the miles of canals.

An installation is made up of modules that each generate 5-25 kilowatts but Morris said the company would never deploy a single turbine, just as a solar company would not install a single solar panel on a roof.

"We need everything we can get from all of the renewable energy sources," said Dan Reicher, senior scholar at the Stanford University School of Sustainability. "So I do think this energy generation is meaningful." It's also environmentally low impact, he said.

Daniel Kirschen, an engineering professor at the University of Washington made the same point. "If we can generate a reasonable amount of power from them, it's very useful," he said.

Traditional large-scale hydropower projects have faced scrutiny for their environmental impact, including submerging communities, slowing rivers, and blocking fish migration. Some are being demolished. On the other hand, they generate enormous amount of energy, as long as it rains and snows.

The Emrgy systems connect to the grid the same way any distributed wind or solar does. Sometimes electric distribution lines run right along canals. The turbines can be installed quickly without lengthy permitting.

"I've watched how solar has risen to dominate the renewable energy mix over recent years," said Morris. "We know the faster we can generate new power means we will be more impactful and can grow."

Emrgy's systems are currently in use at Denver Water, Oakdale Irrigation District in California, a district in Salt Lake City and one in New Zealand. The company has a pilot in South Africa and is expanding

The spinning turbines do change how the water moves through the canals, slowing it, so Emrgy works closely with water operators.

Traditional large-scale hydropower projects have faced scrutiny for their environmental impact, including submerging communities, slowing rivers, and blocking fish migration. Some are being demolished. On the other hand, they generate enormous amount of energy, as long as it rains and snows.

erobz said:

There is going to be a scaling limit since the irrigation channels have a primary objective that depends on design flowrate and probably delivering un-stagnated water to crops. They are at least acknowledging that in the article, as well as the failures associated with the already implemented technology.My problem is never with the "green energy source", but how they usually fail to illuminate the many potential drawbacks when they are pushing for it. I find it fascinating that the engineers of the technology failed to figure out the upstream/downstream effects before the tech was implemented on any scale. My guess is they did, and it was ignored for political reasons. Sad. No doubt a bunch of wasted taxpayer money that could have served much better elsewhere.

At least this company seems to have a reasonable/cautious approach without promoting pie in the sky optimism. That is something I can get behind.