Photo courtesy of Marshall Municipal Utilities In this photo, electric crews from Marshall Municipal Utilities performed maintenance on part of the city’s underground cable system last year. MMU has received national recognition for its reliability in 2020, partly thanks to maintenance efforts like this.

MARSHALL — Keeping the lights on for Marshall residents and businesses is a big job, and one that’s involved more than a decade of updates to the city’s electrical infrastructure. But it’s had good results, said Marshall Municipal Utilities Electric Operations Manager Steve Johnson.

“Our customers had power almost every single minute of the year in 2020,” with a reliability index of more than 99%, Johnson said. MMU has received national recognition for its reliability last year.

“We’re very proud of what we’ve accomplished,” Johnson said. He said credit for that accomplishment is shared by all of MMU’s staff.

The American Public Power Association (APPA), a trade group representing more than 2,000 community-owned electric utilities, awarded MMU a Certificate of Excellence in Reliability in 2020. The APPA has also named MMU a Reliable Public Power Provider. The designation lasts for three years, and a total of 270 public electric utilities are currently designated Reliable Public Power Providers, the APPA said.

A total of 15 utilities in Minnesota, including MMU, are Reliable Public Power Providers.

Johnson said the APPA looks at statistics submitted by electric utilities in issuing awards and recognitions.

Since about 2012, MMU has used computer software to measure its electric reliability in a few different categories, Johnson said. The information helps the utility evaluate how it’s operating and serving customers.

“One of the measures we use is ASAI, the average system availability index,” Johnson said. The ASAI helps measure how much time customers had power during a period of time. In 2020, MMU had an average system availability of over 99.99%.

“Customers in Marshall are very fortunate to have that high reliability,” Johnson said. Over the past five years, MMU has ranked highly for electric reliability compared with other utilities in a seven-state region, he said.

A big part of what has allowed Marshall to have such reliable electricity is the work that’s been put into updating power lines and moving them underground. MMU started burying its overhead power lines in 2004. By 2012, around 92% of the lines were underground. Today, about 95% of Marshall’s electric lines are underground, including all of the city’s residential power lines, he said.

“When we have windstorms or ice storms, or even lightning storms, it doesn’t affect us as much as cities with overhead lines,” Johnson said.

Another factor that has helped with reliable electricity is a six-year project MMU undertook to replace high-voltage cables in Marshall. Starting in 2014, MMU crews replaced electric lines with cable dating back to the 1980s and 1990s, Johnson said.

Johnson said 99.99% reliability doesn’t mean that Marshall hasn’t seen power outages. In recent years, MMU has had outages caused by animals — like the time in 2016 when a squirrel touched a high voltage bus at the Saratoga Street electrical substation. But while the outages affected parts of the community, “they were very short-term events,” Johnson said.

Keeping the power running consistently is a job that takes teamwork from a lot of people, Johnson said. MMU has good leadership from its utility commissioners and management team, who in turn have supported the staff needed to maintain the system, he said.

“They understand the importance of reliability,” he said. “And our staff works hard to keep it at that level.”