DTE and Consumers Energy had “worse than average” service interruptions, restoration delays, and tree trimming cycles compared to other utility companies, according to an audit conducted by an independent party.

The Michigan Public Service Commission said it hired Liberty Consulting Group, based in Pennsylvania, to audit both companies in 2022 “amid a string of widespread outages and public frustration with unreliable service.”

The consulting group will present its findings at a commission meeting Thursday in Lansing.

The audit compared DTE Electric and Consumers Energy to two other investor-owned companies, Commonwealth Edison and Ameren Illinois, and the Lansing Board of Water and Light, a municipal electricity company.

The consultant group held over 150 meetings, 50 of them with managers, executives and employees at both companies for over a year.

“This audit is the first of its kind in Michigan, exploring the equipment and operations of the two utilities that provide electricity to more than 80% of Michigan electric customers,” said Dan Scripps, chair of the MPSC, in a press statement. “It provides an unprecedented examination of the condition of the electric grid serving those customers, an incredibly valuable tool as the MPSC continues its work to reduce power outages, shorten the time for restoration of power after storms, and keep residents safe when power lines come down.

State regulators released the audit Monday. The report found that in 2022 and 2023, the average time it took for both utility companies, which serve about 4.1 million customers, to restore power outside of major weather events was worse than average among other utility companies.

In 2023, over 13% of DTE Electric customers experienced four or more outages and 45% of customers experienced outages that lasted eight hours or more.

In the same year, more than 10% of Consumers Energy customers experienced four or more outages and over 25% of them had outages that lasted at least eight hours.

The audit also found that both companies have outdated infrastructure which could be the cause for the long-lasting interruptions.

Roughly 45% of DTE customers are served by an underground system which takes longer to locate and fix and puts workers at a higher risk of electric shock, according to the audit.

“We remain laser-focused on delivering on our commitment to our customers — reducing power outages by 30% and cutting outage time in half by 2029,” said Matt Paul, president of DTE Electric, in a press statement Monday.

“To meet that commitment, as well as the customer service standards set by the Michigan Public Service Commission, we’ve been making significant investments as part of our accelerated plan to quickly transition to a smarter grid, aggressively trimming trees, updating our existing infrastructure and rebuilding significant portions of the grid,” Paul said.

DTE requested a $456.4 million rate increase in March which would increase customer rates by 10%, costing the average customer an extra $135 per year.

Attorney General Dana Nessel in her testimony to the MPSC in July said that the rate hike should be no more than 2.5%.

Customers opposed to the rate hike spoke during a public hearing on Sept. 18 in Detroit and said it would cause affordability problems for customers who already have to choose between paying their electricity bill and buying groceries.

About 62% of Consumer Energy’s low voltage distribution poles are considered small-diameter, which are more likely to break during storms, the audit shows.

“The MPSC audit on our company’s storm response has been constructive, and we appreciate the deep experience and expertise Liberty brought to the process,” Brian Wheeler, spokesperson for Consumers Energy, told Bridge Michigan. “Consumers Energy proactively provided data, information and access to our facilities to Liberty.”

The audit also found that both companies’ tree-trimming schedules are behind those of other utility companies.

DTE aims to have trees trimmed every five years but the current cycle is every five to seven, according to the audit. Consumers Energy currently has a tree trimming goal of five to nine years but, according to the audit, the utility is trimming trees nearly every 10 years.

Utility companies that have shorter vegetation management cycles don’t have nearly as many outages, which can be a cost-effective way to reduce outages.

“The results from this audit will inform our next steps and strategies to make the electric grid more resilient and reliable,” said Commissioner Katherine Peretick. “It provides unprecedented transparency into the utilities’ infrastructure and operations and allows us to make better decisions to improve service and affordability for Michigan customers.”

This article is being republished through a syndication agreement with Bridge Michigan. Bridge Michigan is Michigan’s largest nonprofit news service and one of the nation’s leading and largest nonprofit civic news providers. Their coverage is nonpartisan, fact-based, and data-driven. Find them online at https://www.bridgemi.com/.