18-17: Changes Through the Years, Great River Energy Coal Creek Station

This presentation will summarize the evolution of the plant and detail some of the major changes/improvements thru the years. This includes new concrete circulating water piping, a coal drying system, the addition of variable frequency drives on the cooling tower fan motors, and the replacement of the cooling tower fill rings. Coal burns. Water doesn’t. That is the founding principle behind DryFining™, a lignite fuel enhancement system which includes both drying and refining lignite. As a result of the research efforts and our partnerships with other companies, Great River Energy is DryFining all of the coal used at Coal Creek Station. The three cooling tower fill rings have each been replaced twice. The first series of replacements were in kind with wood structures but with various fill bar arrangements. The most recent replacements, 2008, 2014, and 2017, were evaluated and have been upgraded to a fiberglass structure. With the fiberglass conversion, areas of maintenance issues thru the years were addressed and improved. The positive features of the new fiberglass structures will be explored. Variable frequency drives (VFD) were added in 2003, 2004 and 2005 for energy conservation. These results and the changes in operation will also be discussed. The new fill rings also incorporated the latest in splash fill technology and a significant performance increase was achieved. Utilizing both the VFD’s and increased efficiency, operational flexibility and energy savings has been achieved. Operating changes and results for both the cooling towers and the units will be discussed, focused on energy usage and power demands.