Dr. Rajiv Mishra thinks the ancient past and the modern present are converging in some ways. “In the past,” Mishra says, “we have prayed to the sun god, to the wind god and to the water god. Now we are back to that point.”
Mishra, Curators’ Professor of materials science and engineering at Missouri University of Science and Technology, 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.
Missouri, though landlocked, 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,” Mishra says.
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 produced by dams, which rely on gravity to make electricity via water and generators.
The energy produced kinetically could be used locally to decrease dependence on power currently derived from coal and nuclear plants. Many big cities in the U.S. are located on major rivers, including Kansas City and St. Louis, which are on the Missouri River. 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. Mishra currently has a few demonstration models in his laboratory.
Among the other Missouri S&T faculty members working on the interdisciplinary project are Dr. K. Chandrashekhara, Curators’ Professor of mechanical and aerospace engineering; Dr. Xiaoping Du, associate professor of mechanical and aerospace engineering; Dr. Arindam Banerjee, assistant professor of mechanical and aerospace engineering; Dr. Jonathan Kimball, assistant professor of electrical and computer engineering; and Dr. Joshua Rovey, assistant professor of mechanical and aerospace engineering.
According to Rovey, gages 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.”
A post-doctoral student and ten other S&T students, including two undergraduates, are also working on the research, which is being funded by the Office of Naval Research.
Eventually, Mishra and his team plan to have a prototype that can be marketed to companies in Missouri. “Some companies in other states are already making hydrokinetic systems,” he says. “But so far, nothing in Missouri.”