Interconnection Standards

Note: As of May 2024, utility-specific interconnection rules proposed by Michigan's various investor-owned utilities are currently under review by the Michigan Public Service Commission (MPSC). The new rules must incorporate changes required by Public Act 235 of 2023.

Michigan adopted new statewide interconnection standards, the MIXDG rules, in 2023.

The new interconnection standards use a five-tier system similar to previous rules, but with fast-track processes available for all tiers. The five tiers are:

• Level 1: Certified, 20 kW or less
• Level 2: Certified, 20-150 kW
• Level 3: Not certified, 150 kW or less, or 150-550 kW
• Level 4: 550 kW- 1 MW
• Level 5: Greater than 1 MW

Fee amounts may not exceed: 

•  $300 for the pre-application report
• $100 + $1/kW for certified DERs and $100 + $2/kW for non-certified DERs for the non-export track
• $100 + $1/kW for certified DERs and $100 + $2/kW for non-certified DERs for the fast track initial review fee
• $1,000 for a fast track supplemental review
• $300 for the study track interconnection application review and scoping meeting
• $10,000 for the system impact study
• $15,000 for the facilities study

Tracks available include the non-export track for systems that will not export electricity to the grid, the fast track for systems that will not interconnect with the utility's high voltage distribution system, and the study track for systems that do not qualify for the other tracks or do not pass initial reviews in the other tracks.
Insurance is not required for level 1 or 2 projects. Level 3 projects must have at least $1 million in insurance, level 4 projects at least $2 million, and level 5 projects at least $3 million.
Customers using energy storage devices in conjunction with generation shall not use the energy storage system to provide output exceeding 100% of the customer's electricity consumption for the previous 12 months. Addition of storage to a pre-existing generation system is a material modification that requires a new interconnection application. Utility interconnection procedures must include details describing how energy storage can be integrated into existing legacy net metering program systems without affecting the 10-year grandfathering period or participation in the distributed generation program.

If necessary to promote grid reliability or safety, the MPSC may promulgate rules that require the use of inverters that perform specific automated grid-balancing functions to integrate distributed generation onto the electric grid.