Search is currently unavailable. Please try again later.
The web Browser you are currently using is unsupported, and some features of this site may not work as intended. Please update to a modern browser such as Chrome, Firefox or Edge to experience all features Michigan.gov has to offer.
All MPSC workgroup meetings are being conducted via teleconference. Remote access information for upcoming meetings is available on our calendar of events.
Public Act 235 establishes a statewide energy storage target of 2,500 MW. By Dec. 31, 2029, IOUs will need to file petitions for approvals related to the storage target and Alternative Electric Suppliers will need to file plans for how they will comply with the target. Investor-Owned Utilities (IOUs) are required to begin filing annual storage no later than Dec. 31, 2024. Public Act 235 also directs the Commission to complete a study on long-term and multi-day energy storage systems by February 27, 2025.
On February 8, 2024, the Commission initiated Case No. U-21571 to undertake the work required to develop the storage targets and provide guidance on the required annual storage reports. Staff was also directed to complete a study on long-duration and multi-day energy storage systems as required by Public Act 235.
Implementation Status: In Process
Lead Staff: Jon DeCooman
On February 8, 2024, the Commission issued an Order in Case No. U-21571 issuing guidance for Public Act 235 of 2023, Sections 11(1)-(9) and 103.
On January 23rd, 2025, the Commission issued an Order in Case No. U-21571 adopting Staff’s straw proposal, with modifications as necessary, for the calculation methodology for utilities and alternative electric suppliers to determine their proportional share of the minimum statewide energy storage target.
The Commission also directed rate-regulated utilities to file individual energy storage reports in accordance with the Commission guidance in U-21571.
Staff has completed its study on long-duration and multi-day energy storage systems, and it has been filed to the docket for Case No. U-21571. It has also been provided on this page below.
Staff's Storage Target Straw Proposal
Study of Long-Duration and Multi-Day Energy Storage
Meeting Event | Agenda | Presentation | Recording