Cobb Electric Membership Corporation, a large (206,000-member) cooperative serving just outside Atlanta, Georgia, received positive attention recently for its innovative use of data in a practice called consumer segmentation. With segmentation, Cobb EMC can accurately assess the preferences of different groups of consumers for products and services. But Cobb EMC has also been addressing consumer service through data analysis in another way in recent years, through its use of the PwrMetrix software to address outages and improve reliability.
Before a recent promotion to manager of distributed energy resource strategies at the cooperative, Manish Murudkar oversaw distribution system protection and planning at Cobb EMC for six years, which included the introduction and initial use of PwrMetrix in the task of calculating and addressing reliability.
Before using PwrMetrix, Cobb EMC experienced annual outages per consumer of more than 40 minutes, according to the SAIDI (System Average Interruption Duration Index) calculations. With the proactive system maintenance undertaken as a result of the information obtained through PwrMetrix, the SAIDI numbers have dropped into closer to 30. Murudkar notes that this has moved the co-op into third in the nation among utilities participating in distribution reliability benchmarking by IEEE.
Manish explains that system operators in Cobb EMC’s control center input data on outages into a SharePoint table. “We have an OMS that we can [also] pull data from but to avoid error we track all data – every outage start and end time – with this manual process,” he says. Once complete, that data is imported into PwrMetrix, where the reliability calculations are performed and reports issued for use by cooperative staff.
“The use of PwrMetrix improved our productivity in calculating reliability, “says Murudkar. With analytical reports “delivered with a flash of your fingers” Cobb EMC is able to drill down into the causes of outages. He says that PwrMetrix “helped us identify the major issues – animal-caused outages, storms and vegetation – and pinpoint which feeders are the worst performing.” With this information, Cobb EMC made changes to its vegetation management program, designing and implementing a right-of-way program that covers all cooperative feeders on a five-year cycle.
“There is a wealth of reporting capability in the PwrMetrix tool,” says Murudkar, including the ability to pull up the SAIDI results for any point on the utility system. Similarly, it calculates the SAIFI numbers (frequency of outages) with the same granularity. Understanding frequency is important, he says, to be able to take preventative measures before trouble develops. “If we see a spike in outage frequency at a particular location, we know that something is wrong there, and if it’s not taken care of, could lead to a bigger problem than a single fuse blowing up.” This detailed visibility leads to improved productivity. “We focus on where the issues are and take prompt action to address them,” he says.
Other reporting functionality of high value to Cobb EMC include:
- SAIDI comparisons month-to-month and year-to-year;
- Identifying the overlay of outages to major events outside the control of the co-op (such as weather), which can lead to higher accuracy in calculating “true” system reliability, and,
- Calculating outage costs to the customer, to the cooperative and by location, which informs preventative maintenance schedules.
“Our industry is changing and using and understanding data is becoming more important to our future,” says Murudkar. “Benchmarking is one of the keys to tracking our reliability. A tool like PwrMetrix helps us understand where we need to direct our resources to make a positive difference in our service and in the eyes of our consumers.”
