Backup transformer stored on-site will improve response if current transformer needs replaced

EnergyLines September 2018


If the step-up transformer at the Merom Generating Station fails, it can take as long as a year to repair or replace. It’s best to take precautions in advance and have the equipment already purchased and waiting. This saves time and money in the event of an emergency outage. To improve reliability for member co-ops, Hoosier Energy has a back-up transformer on location. Early in September, a spare transformer was transported from Mexico and delivered to the Merom Generating Station in Sullivan, Ind. by rail.


Once on site, crews began working to unload the 283,475 pound transformer on Aug. 8 onto an eight-axle transporter using a hydraulic slide system. The transformer was then transported to the concrete pad adjacent to the primary substation at the plant, where it will reside until needed.


Since this transformer can serve several sites, relocation time will vary with its destination – ranging from 2.5 weeks to a month. The process of specifying, manufacturing, ordering and receiving a transformer of this magnitude can easily take a year.


In the case of an emergency outage, trying to expedite the process to obtain a replacement transformer tends to increase the costs and mistakes. Mark Hall, Hoosier Energy’s Substation Design Engineer, said, “In short, it is wise and responsible to be prepared. In this case, we save 11 months and possibly hundreds of thousands of dollars.”


“Having this spare on hand reduces our outage time, thereby increasing our reliability and minimizing our need to purchase power,” he added.


A prolonged outage at this level restricts maintenance practices, which in turn, adversely affects reliability on the entire system – including our service to our cooperatives.


The delivery of this transformer prompted an overall inspection of the health and condition of the railroad spur coming into the Merom Generating Station. The subsequent upgrades will serve future deliveries into the plant and assure that this transformer can be relocated elsewhere should the need arise.


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