September 2015
D U N C A N’S D I G E S T Over the ten years since named hurricanes blew through Florida, SECO Energy has continued to invest in system improvements that “harden” our infrastructure in preparation for not only the next major hurricane but also for small storms that occur. Moreover, these upgrades improve system reliability on blue-sky days as well. After the hurricanes of 2004 when some utility providers’ systems did not hold up well to the wind, rain and storm surge, the Florida Public Service Commission (PSC) enacted Administrative Code (Rule 25-6.0343) requiring municipal and co-op utilities to file annual reports with the PSC. Investor-owned utilities also file with, and are accountable to the PSC. SECO Energy’s design and construction standards, policies, and procedures comply with Rural Utilities Service (USDA-RUS) guidelines and the National Electrical Safety Code (NESC). Our distribution facilities are designed to withstand 110 mph winds, and the system is evaluated continuously for storm hardening and system upgrades. Annually, our company spends about $27 million on system maintenance, $9 million on improvements, and $8 million on vegetation management – all ensuring the most reliable, efficient delivery of power to you.
In 2007, SECO developed a rigorous program to conduct the following inspections: eight-year rotational five-year rotational three-year rotational inspection cycle: inspection cycle: inspection cycle: Every distribution pole Thermographic imaging Vegetation management on the system All components of every substation All underground facilities
of critical circuits All transmission poles
around lines, transformers, pedestals, etc. 410018
After researching results of previous years’ pole inspections, SECO began a five-year plan in 2011 to replace all wood transmission poles with spun concrete poles that are set 30 feet into the ground. The data made it clear that woodpecker damage, toward the top of the pole, is the leading cause of poles deteriorating prematurely and that pole rot at the bottom was not a large contributor. Given the hurricane-force wind risk and the ravenous woodpeckers in our area, spun concrete was the answer. The photos to the left tell the “before and after” story from an occurrence on July 29th with a wood pole in the transmission corridor between the Anderson and Lake Panasoffkee substations. The broken pole shows substantial woodpecker damage. Ironically, the new concrete pole to replace the one that broke that night was set just prior to the wood pole breaking. The conductors were transferred the next day to AFTER BEFORE the concrete pole. It’s also important to note that on the night this wood pole broke, members did not experience an interruption due to the combination of state-of-the-art substation design (called a “ring bus” system) and quality construction. The system redundancy is intentionally designed with backup power sourcing from the Bushnell substation into the Lake Panasoffkee substation, allowing the power flow to continue automatically through another circuit despite the wood pole failure. This ring bus design redundancy has been applied to most substations across our system to create parallel power source options when anomalies occur. Our Lady Lake substation is another example of the inspection cycle resulting in proactive system improvements. Substation inspections are comprehensive - with many of the large components being removed from service, taken apart and inspected in detail. The most recent Lady Lake substation preventative maintenance inspection Continued next page ...