Developer • City of Quincy

Proposed sites: Lock & Dams No. 21, 24 and 25 (Quincy, Clarksville, Mo., Winfield, Mo.)

Details: Quincy is seeking a federal license to build a 15-megawatt hydroelectric project on its riverfront. The city hopes to use a federal stimulus grant to pay for 30 percent of the $100 million project. Quincy is also studying sites at Lock & Dams No. 24 and 25 for future development.

Developer • Hydro Green Energy LLC

Proposed sites: Lock & Dams No. 20, 22 and 27 (Canton, Mo., Saverton, Mo., Granite City)

Details • Houston-based Hydro Green Energy is proposing to install pre-fabricated modules, each with several hydroelectric turbines, in a specially designed conduit adjacent to the locks and dams. Each turbine would be about seven feet in diameter.

Developer • Free Flow Power Corp.

Proposed sites: Hickman, Ky., New Madrid, Mo., Wickliffe, Ky., Columbus, Ky.

Details • Each site would include thousands of 3,000-pound turbines arranged into fields, or arrays, and moored to the river bed using pilings, a barge-like platform or existing shore infrastructure.

Developer • Brookfield Renewable Power Inc.

Proposed sites: Melvin Price Locks and Dam (Alton)

Details: Brookfield acquired a license to build the hydropower project through its 2007 acquisition of Price Dam Partnership Ltd. The company is asking federal regulators for a license amendment because it's proposing to use a different technology than the original license holder. The existing license also required construction to begin in July.

Developer • McGinnis Inc.

Proposed sites: Downstream of the Melvin Price Locks and Dam (Alton)

Details: Barge-builder McGinnis proposed to install as many as 10 turbines mounted on a barge attached to the riverbed. Electricity generated by the turbines would be transmitted to shore via high-voltage cables.