Moving water carries with it an enormous amount of kinetic energy. Wave power technologies all the way down to to tiny turbines in city water pipes aim to harness that energy. A new hydropower technology from Seattle start-up company Hydrovolts taps a plentiful but overlooked source of renewable energy from the water currents in irrigation canals and other small channels around the world.
As Grist reports, Hydrovolts' hydrokinetic device sits right on a canal’s concrete floor, but the turbines could also be placed in spillways, water treatment plants, and other places where water flows through a human-made structure free of snags.
The energy output of the turbines depends on the velocity of the water running through it. According to the company's website, water flowing at 1 m/s would produce 0.4 kW, a flow of 2 m/s would produce 4 kW, and water flowing at 4 m/s would produce 32 kW. Not a tremendous amount of energy, but one placed in a canal could power several homes and also pay for itself in energy savings within five years.
The efficiency of the turbine depends on the type of water source. If it is a canal and most of the flow can go through the turbine, the efficiency can reach 60%, but in more open channels the efficiency would be somewhere between 15 and 30 percent.
You can see the turbine in action in the video below.
“There are huge regions of the world that are irrigated, where they have built these highways of water,” said Burt Hamner, founder and CEO of Hydrovolts. “We’ve found a way to make a little power off it without any environmental impact.”
The U.S. Bureau of Reclamation, which owns and operates thousands of miles of canals has installed a prototype of the turbine in the Roza Canal in Washington, which is part of a system that delivers Yakima River water to 136,000 acres of Washington farmland. The installation is part of the bureau's plan to tap 500 of its canals for energy generation to reduce the amount of fossil fuels used to pump and manage the water or even to be sold to cut down on operating costs. The pilot project has generated as much as 8 kW from the canal.
The bureau wants to test the technology more before deploying a more extensive network of the turbines to make sure they don't affect the water flow or quality. A big question is whether the canal would still operate smoothly if the turbine were to fail.
Hydrovolts hopes to eventually place its devices throughout the world's canals. The turbines are expected to hit the market in a couple of years at $20,000 a piece.