With an elevation of less than 15 feet, low-head dams have a tendency to be ignored. There are more than 72,000 of these dams across the United States, most of which were built prior to 1950 on rivers that were not used for commercial purposes. Although the dams have provided flood control and a reliable water source for industrial sites adjacent to them, their potential for the generation of hydroelectric power has been overlooked – at least, until now.
The Williams Cross-Flow Turbine, developed by Hamilton, Ohio-based KWRiver Hydroelectric, is designed to change that. The device can capture the power of the flow of water over the weir of a low-head dam.
“It’s about how much water you can get through there per second,” a company representative explains, adding that the turbine can fit into dams with little or no structural modification needed.
“Once we get in there, put it in place and anchor it down, that’s it,” the company says. “[When the water] starts flowing in and turns the generator, we make electricity, and we’re able to put it in the distribution grid.”
The device was developed by company Partner Fred Williams, who founded KWRiver Hydroelectric in 2013 with Paul Kling, a 30-plus year energy industry veteran who previously worked for Duke Energy in various capacities.
Williams was awarded patents for the turbine in 1999 and 2005. He tested the device with the help of the Electric Power Resource Institute at Central State University (CSU) in Wilberforce, Ohio, which provided funding. Laboratory testing included building a scale-model dam and a 70-foot hydraulic flume, which simulated river conditions.
Flowing with Potential
KWRiver Hydroelectric’s home state of Ohio presents it with several opportunities to put its technology to use. The state has more than 200 potential dam sites capable of using the turbine.
KWRiver plans next year to install the first prototype in Ohio’s Great Miami River’s south dam, which will make it safer. There have been two fatalities at that dam in the past 10 years as a result of water flowing back on itself and creating a hydraulic boil, which a person can easily get caught in.
When installed, most of the water will flow through the turbine and eliminate the boil. Each turbine is designed to generate between 50 and 300 kilowatts of energy. The company hopes to place turbines at low-head dam locations where five or more of the units can be placed at a time, which would enable the production of more than 1.5 megawatts of power. This is enough energy to supply 1,000 average homes, the company notes.
KWRiver has generated interest in the turbine, but licenses and permits represent challenges since they were “not set up for [something] of this size or technology,” the company says. “They were set up for large dam sites, like the Hoover Dam.”
Although the company is navigating these hurdles at this point, it asserts that support is strong for hydropower development from the Department of Energy and the Federal Energy Regulatory Commission. “It’s better than wind power and solar power because it’s a 24-hour reliable product,” KWRiver Hydroelectric says. “There’s a lot of effort moving forward to push that technology, but the environmental permitting hasn’t caught up with us yet.”
Abundance of Ideas
KWRiver is confident in the turbine innovation’s future. Two additional patents for the technology are pending. These patents are related to enabling the turbine’s electric generator to be placed on shore. “There really isn’t a technology that comes close to ours,” the company says, noting that the product has been designed to be durable.
The turbine also is built to be environmentally friendly. “What we attempted to do was keep the rotational speed of the turbine less than 60 revolutions per minute,” it adds, noting that this prevents small fish that slip inside the turbine from being hurt. “We’ve got lots of good ideas coming through.”