Hybrid Solution Saves St. Charles Utility More Than $4 Million, Improves Reliability
Estimated costs for the St. Charles Municipal Electric Utility cable replacement needs came in at about $6.6 million. St. Charles chose a solution comprised of 77 percent Novinium® cable rejuvenation and 28 percent cable replacement, saving $4.3 million, or 66 percent of the original project estimate.
- Rejuvenated 169,829 feet and replaced 50,127 feet of cable
- The utility saved $4.3 million, or 66 percent of the original project estimate
- Rehabilitated subdivisions experienced a 96 percent reduction in failures
The Company and the Situation:
The St. Charles Municipal Electric Utility, located along the Missouri River just outside of Chicago, Ill., already knew it faced a large volume of aging underground residential distribution (URD) cable. The utility decided to track cable failures in greater detail after experiencing a steady increase in outage rates. The resulting data clearly showed the problem subdivisions, which were not necessarily the ones with the oldest electric lines.
St. Charles Utility Senior Distribution Engineer Stephen Shroba designed a strategic asset management plan to identify, prioritize, and then address the areas of the St. Charles system with the highest failure rates. As part of the plan, the utility developed a priority matrix that included the number of faults, randomized VLF tan delta testing, age of the cable, and each fault’s impact on customers. The cost to replace all the affected cable was estimated at $6.6 million and the project was going to be quite difficult logistically