Hydrokinetic energy on the Mississippi

A new bill in Louisiana may help Massachusetts start-up Free Flow Energy harness the power of the Mississippi River. Could in-stream technology become the hydro of the future?
Written by Melissa Mahony, Contributor

Louisianians may soon find another energy source within their waterways. No, not the Gulf of Mexico, but beneath the surface of the Mississippi and Atchafalaya rivers.

And the energy won't come from damming up the rivers, but by letting them flow—the faster, the better—via in-stream hydrokinetic energy.

If made law, Louisiana Senate Bill 183 would let the state rent out land—in this case, river space—for the development of renewable energy. The bill has passed the Senate and now awaits the House.

The Federal Energy Regulatory Commission granted Free Flow Power (FFP) 60 preliminary permits in 2008 to test sections of the rivers, where the currents are strong and consistent, to submerge slow-spinning turbines.

Free Flow Power's almost 10-foot turbines are meant to sit passively in the river, generating about 10 kilowatts in 7.4-feet-per-second flows and 40 kilowatts in 10-feet-per-second currents.

Last week, the Associated Press quotes FFP's Jon Guidroz:

The U.S. has never developed its own form of renewable electricity. We have an extraordinary river resource no one else has...This is an opportunity the United States has never had.

In the upper stretches of the Mississippi, Hydro Green Energy launched in August the country's first licensed, commercial in-stream hydrokinetic project north of Hastings, Minnesota. This energy system sits downstream from a more traditional hydropower operation, a dam (the Army Corps of Engineers Lock and Dam No. 2). Dams highly disrupt rivers and surrounding ecosystems.

With in-stream turbines, one impact that comes to mind is whether they fillet the fish swimming through them.

According to a report released and conducted by Hydro Green Energy in January, fish passing through their turbine had a 97 percent survival rate. The company is also planning a project at the Amory Lock and Dam on the Tennessee-Timbigbee river.

Images: Free Flow Power (top) and Hydro Green Energy (bottom)
: IEEE Spectrum

This post was originally published on Smartplanet.com

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