On July 1, the City of Guttenberg, Iowa, applied at the Federal Energy Regulatory Commission for a successive preliminary permit for the 25-MW Guttenberg Water Power Project.
The proposed project will be located at the existing U.S. Army Corps of Engineers’ Lock and Dam 10, on the Mississippi River in Clayton County, Iowa, and Grant County, Wisc., near Guttenberg, Iowa.
In July 2010, the commission granted the city a preliminary permit to study the feasibility of the proposed project. During this time, the city said it has diligently pursued the potential options for hydro development at ultra low-head sites. The city said it continues to have discussions with firms developing applicable low-head technology and has been monitoring low-head technology testing at the University of Iowa’s IIHR Hydraulic Laboratory. The city is also in discussions with Amjet Turbine Systems LLC of Keokuk, Iowa, a manufacturer of low head turbine/generator units.
“Although hydro development at low-head sites presents many challenges, discussions with the above referenced firms have been promising,” said the July 1 filing. “As such, the City would like to maintain priority of application for license and continue to pursue site development options through the successive preliminary permit period to ultimately culminate with the submittal of a license application for the Project.”
Working with Missouri River Energy Services (MRES), the city said it has developed a preliminary energy model for the site. Using river data from February 2003–May 2011, it assumes the installation of a traditional powerhouse with five new pit type horizontal turbines with a 6.5 meter runner diameter and a capacity of about 5 MW each, for a total installed project capacity of 25 MW. The average head is estimated to be between 6.5 and 7 feet. The city has assumed the completed project would produce around 79,300 MWh annually using a capacity factor of 36%.
Additional analyses and specifications of the design, including investigations of low-head technology, will continue to take place during the period of the successive preliminary permit. The proposed system will allow the Corps of Engineers to instantaneously override and/or modify hydroelectric operations in response to emergencies related to Corps operations at the dam.