Third-party audit finds slow inspection cycles, costly legacy circuits and recommends longer planning horizon

The Michigan Public Service Commission heard a summary of an independent distribution-system audit on Sept. 26, 2024, that finds Consumers Energy and DTE Electric need faster inspection and vegetation-management cycles, clearer data to measure benefits of reliability investments, and better restoration budgeting.

John Antonuk, co-founder and president of Liberty Consulting Group, told the commission the engagement included a physical inspection of infrastructure and a review of programs and procedures. He said Consumers’ vegetation-management cycle effectively spans 10 years and will not reach a four-to-five-year industry norm under current plans, and that Liberty “strongly emphasize[d] that establishing in the near term a four- to five-year overall vegetation cycle should be a first priority” for Consumers Energy.

Antonuk flagged DTE’s visual overhead inspection cycle as particularly long—about 20 years at the time of the audit—and called a planned reduction to a 10‑year cycle still “more than twice as long as the typical four- to five-year” practice used elsewhere. He also raised a separate, large-scale concern for DTE: a legacy population of 4.8 kV circuits that serve roughly 40% of DTE customers and whose elimination could cost the high end of the company’s estimate, “as much as $20–25 billion.” Antonuk said such a program would dwarf the companies’ planned spending through 2028 and recommended evaluating longer planning durations (10 years) to weigh reliability goals against price impacts.

On emergency planning, Antonuk said the companies’ storm-response structures are appropriate but noted both failed to meet “wires down” relief-factor metrics in 2023, and that restoration-budgeting methods based on five-year averages have produced repeated large overruns. He recommended improved forecasting of restoration costs, clearer accountability for restoration budgets and more testing of outage-communications systems.

Chair Dan Scripps (MPSC) thanked Antonuk and staff and noted the audit has been filed in docket U-21305. Commissioner Partic emphasized the audit’s practical goal: identify where to invest to improve reliability, and asked utilities to prioritize safety-related recommendations. The commission voted to approve an order directing the utilities to file responses and invited comments in the docket; the order stresses immediate safety work, compliance with rules and long-term planning improvements.

The audit team and commissioners repeatedly cautioned that visible improvement at the customer level will take time—measured in multiple inspection or vegetation cycles—and that large near-term expenditures will have electricity price implications that the commission should consider in longer-duration planning comparisons.

The audit report and supporting materials were filed in docket U-21305 and are available on the commission’s website. The commission’s order on the audit requests utility responses and invites interested parties to comment by Dec. 15, 2024.