Assembly Bill 901 aims to enhance net metering for rooftop solar energy systems in Wisconsin by establishing clear guidelines for electric providers regarding interconnection and billing practices. The bill prohibits electric providers from denying interconnection based on the generating capacity of rooftop solar systems, provided they do not exceed 500 kilowatts for commercial buildings and 30 kilowatts for residential buildings. Additionally, it specifies that the capacity of associated battery energy storage systems cannot be included in these calculations. The bill mandates that rooftop solar systems must include advanced metering infrastructure and allow for meter aggregation to connect to electric distribution facilities.

Furthermore, the bill requires electric providers to create a standardized net metering agreement for customer-owned rooftop solar systems that meet the specified capacity limits. Under this agreement, customers will receive a credit valued at 100% of the retail electricity rate for any excess electricity generated and delivered to the grid, with credits expiring annually on March 31. If the adoption rate of rooftop solar systems exceeds 10% in a service area, providers may revise the agreement, reducing the credit value to 90% of the retail rate. The revised agreement will take effect 60 days after notification to customers, ensuring that the net metering framework remains responsive to the growth of solar energy adoption.