Float-in Module for Retrofitting Navigation Dams for Power Generation. Volume I. Feasibility Report

摘要

Among the nation's water developments without powerhouses are 136 low navigation dams on inland waterways. The combination of many undeveloped sites and a system capable of transporting large and heavy objects suggested the possibility of prefabricating standardized powerhouses at some facility, transporting the powerhouse modules along the waterways, installing them at the low navigation dams now without powerhouses to generate power with the water now passing through the navigation dams' spillways. DOE awarded a contract to test the feasibility of the prefabricated float-in powerhouse concept by applying it to the low dams without power on the McClellan-Kerr Arkansas River Navigation System. The findings of the feasibility study are presented. The study established that a float-in powerhouse is a viable alternative to a site-built powerhouse. And that there is one main area where a first float-in powerhouse has an advantage over a first site-built powerhouse. The advantage is in the shorter length of the construction period. A float-in powerhouse module can be built at a shipyard at the same time as the foundation is being prepared at the site. A brief Net Present Value study showed that this advantage amounts to many millions of dollars for a two-unit powerhouse at Lock and Dam No. 7 (Murray). The concept of using a standardized design and construction methods to reduce the cost of succeeding powerhouses can be applied more effectively to a float-in powerhouse than to a site-built powerhouse. A powerhouse, either float-in or site-built, for a rim-generator turbine would be shorter and thus less expensive than a powerhouse for a bulb turbine. The saving in powerhouse cost is enough to make the rim-generator powerhouse more attractive at some locks and dams than a powerhouse with a bulb turbine. The rim-generator turbine has the disadvantage of lacking operating experience in the large sizes contemplated for the Arkansas River. (ERA citation 07:042712)