In the near term, Duke Energy Indiana intends to file for a Certificate of Public Convenience and Necessity (CPCN) with the Indiana Utility Regulatory Commission for a major upgrade to the Markland Hydroelectric facility.
This Duke Energy (NYSE: DUK) subsidiary said in a 20-year integrated resource plan, filed Nov. 2 with the commission, that this three-unit facility is located on the Ohio River in Switzerland County, Indiana. Total station generation capacity is 65 MW with a dispatch rating of 45 MW.
Originally entering service in 1967, key generating components at Markland Station are still utilizing original technology. Duke Energy Indiana proposes to overhaul and upgrade each Markland unit from the ground up, replacing most components with more modern, efficient options. The major scopes of work are: replace the station runners and blades with an upgraded, more efficient design; replace the discharge rings and draft tube transition piece; refurbish wicket gates (or replace as needed); rewind the generators; replace excitation controls and voltage regulators; replace and upgrade station controls; procure new intake and draft tube gates; replace the main power transformer; and overhaul and replace the general high voltage electrical systems at the station.
The targeted outage windows for this work are the fall of 2017, 2018, and 2019, with one unit done each year.
As a run-of-river hydro station, the generating units extract as much energy from the flow of the river as possible, within guidelines governed by the U.S. Army Corps of Engineers. With this technology upgrade, Duke Energy Indiana expects to gain approximately 3 MW of incremental design capacity output per unit, along with an expected increase of 36.7 GWh of actual annual average energy production from the station.