PSC setting reliability targets for power companies - Business, Government Legal News from throughout WV

PSC setting reliability targets for power companies

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West Virginia has never held its electric utilities to reliability standards.

But the power outages caused by the storm of December 2009 raised what has in 2012 become a favorite topic among residents too often left sitting in the dark: What can be done to keep the power on?

Discussions among the power providers and the PSC's Consumer Advocate Division and Staff in 2010 led to rules that went into effect in August 2011.

And in September, the power providers and other parties filed with the commission agreeing to targets recommended by commission Staff, effective for the years 2014-2018 if approved by the commission.

The targets Staff recommended rely on three measures of reliability that are standard in the industry.

System Average Interruption Frequency Index, or SAIFI, is the average number of interruptions a customer experiences. This is a measure that online sources say is improved by tree trimming and maintaining equipment. System Average Interruption Duration Index, or SAIDI, is the average outage duration for each customer served, improved by improving SAIFI and by improving outage response time.

Dividing duration by frequency gives Customer Average Interruption Duration Index, or CAIDI: average restoration time.

So, for example, while Appalachian Power's average SAIFI, or number of interruptions, from 2007 through 2011 was 2.33 and its SAIDI, average duration spread across all customers served, was 489 minutes, the optimal targets recommended by PSC Staff are 2.21 interruptions and 489 minutes. CAIDI, or average restoration time, was 210 minutes; Staff recommended 210 minutes.

For Monongahela Power, the average SAIFI was 1.73 for the period and the average SAIDI was 302 minutes, while Staff recommendations are 1.73 outages and 298 minutes. CAIDI was 175 minutes; Staff recommended 175 minutes.

The Staff-recommended targets do not appear to be challenging.

But Consumer Advocate Byron Harris pointed out that Staff also recommended minimum standards and that, when utilities seek rate increases, quality of service will now play into that discussion.

"Performance information has been available but the commission has never had rules setting forth what minimum reliability standards were," Harris said.

Another way that improvements will come is that, when utilities submit required annual reliability reports by May 1 of each year, they will have to list the top 5 percent of the their "worst performing circuits" and planned improvements on them.

"Through time, you should have better and better circuits falling into that worst-performing category," Harris said.

It has to be noted that events like the June 29 derecho and Hurricane Sandy are considered extraordinary: Interruptions caused by "major events"  — those that exceed reasonable design or operational limits of the system — are according to the rules not included in the calculation of the reliability indices.

While improving day-to-day reliability may provide a little more resiliency during the biggest storms, Harris said, he doesn't think much can be done.

Still, overall, he's optimistic.

"I do think the targets are going to make a difference overall," he said.

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