Michigan's renewable portfolio standard (RPS) was increased from 10% in 2015 to 15% in 2021. The RPS applies to all retail electric providers including, investor-owned utilities, cooperative utilities, municipal utilities, and alternative electric suppliers. Michigan's electric providers have an interim compliance requirement of 12.5% in 2019 and 2020.
Compliance with the RPS is demonstrated using renewable energy credits (RECs). One REC is equal to one megawatt-hour of renewable energy. Types of renewable energy include electricity generated from wind turbines, solar photovoltaic panels, biomass, waste-to-energy, and hydroelectric. The RPS law provides "incentive credits" for renewable energy with certain characteristics including on-peak renewable energy generation (not applicable to wind generation) and off-peak renewable generation stored in a battery or pumped hydro facility like Ludington Pumped Storage Facility and used during on-peak hours. An electric provider may substitute a limited number of energy waste reduction credits for renewable energy credits.
The Michigan Renewable Energy Certification System (MIRECS) is Michigan's REC tracking and certification system. Renewable electricity generation is entered into MIRECS and RECs are created. At the end of each compliance year, electric providers show that they have complied with the RPS by moving the required number of RECs, incentive credits, and, if applicable, energy waste reduction credits, into an annual compliance folder which is then submitted to the MPSC for review.
Nearly all of the renewable energy used to meet the requirements of Michigan's RPS is generated in Michigan. Since the first RPS law was enacted in 2008, wind has been the resource most commonly added to fulfill the needed supply of renewable energy. Each February, the MPSC issues an annual report about the renewable portfolio standard.