Missouri has more than 3,000 miles of rivers and Rajiv Mishra wants to use them to harness energy and decrease dependence on power currently derived from coal and nuclear plants.
Mishra thinks the ancient past and the modern present are converging in some ways. “In the past,” he says, “we prayed to the sun god, to the wind god and to the water god. Now we are back to that point.”
Mishra, former Curators’ Professor of materials science, is talking about the three primary sources of renewable energy that Mother Nature produces naturally. Unfortunately, the state of Missouri can’t really rely on getting as much wind and sun as some states. But what the state does have is plenty of water.
Though landlocked, Missouri has more than 3,000 miles of rivers. And the water in rivers flows predictably in one direction.
“Water that is flowing constantly has much more energy potential than wind because of higher power density,” says Mishra, who is now on the faculty of the University of North Texas.
The idea is to put systems resembling wind turbines in running water to produce the energy. This is called hydrokinetic energy, not to be confused with hydro-electric energy produced by dams, which rely on gravity to make electricity via water and generators.
Many big cities in the U.S. are located on major rivers, including Kansas City and St. Louis. Between the two cities, 90,000 cubic feet of water is flowing per second on average. Mishra thinks hydrokinetic energy should be used to help power both metropolitan areas and other towns on the state’s rivers.
Incidentally, Mishra says one study shows that 98 percent of fish that come in contact with the turbines would be fine.
Several different designs for hydrokinetic systems are under development and are being tested on campus. The sizes will eventually depend on the volumes of water in a particular river.
According to Joshua Rovey, assistant professor of mechanical and aerospace engineering and an investigator on the project, gauges are being embedded in the turbine blades as part of a monitoring system.
“With this technology, we can actively monitor the blade health as it evolves over time, significantly reducing operation and maintenance costs,” Rovey says.
Working with Mishra and Rovey are K. Chandrashekhara, Curators’ Professor of mechanical and aerospace engineering; Xiaoping Du, associate professor of mechanical and aerospace engineering; Arindam Banerjee, assistant professor of mechanical and aerospace engineering; Jonathan Kimball, assistant professor of electrical and computer engineering; a post-doctoral student and 10 other S&T students, including two undergraduates. The research is funded by the Office of Naval Research.