Solar PV and Battery Energy Storage Systems (BESS) Equipment

The City of Ann Arbor's Sustainable Energy Utility (SEU) is soliciting proposals for the procurement of Solar PV modules and Battery Energy Storage Systems (BESS) equipment with hybrid inverters to support deployment of 100-150 residential systems networked into a virtual power plant (VPP) pilot. The SEU anticipates purchasing a minimum of 100 systems, with each residential system approximately 5-6 kW DC in size, predominantly installed in rooftop arrays with select ground-mount and ballasted rooftop applications. Offerors may respond with offers for Solar PV modules alone, BESS equipment alone, or both categories, with the goal of system standardization requiring selection of only one type of equipment within each category.

Solar PV module requirements include mono, PERC, or bifacial options with minimum 10-year workmanship warranty and 25-year linear performance guarantee. Modules must be UL 1703 certified and preferably Tier 1 quality. BESS equipment must include lithium-ion batteries with minimum 10 kWh capacity (between 5% and 95% state of charge), hybrid grid-forming string inverters suitable for both indoor and outdoor installation, and battery management systems (BMS) with automated transition capabilities and comprehensive monitoring interfaces. All inverters must be UL 1741 listed with grid-forming capability and compliance with IEEE standards for smart inverter functionality. Bidders/Suppliers must disclose all material sources, fabrication locations, and confirm whether equipment meets Foreign Entity of Concern (FEOC) and domestic content requirements, with financial guarantees of tax credit eligibility where applicable.

Key schedule milestones include written questions due February 9, 2026 by 4:00 p.m. (Local Time), with addenda to be published on or before February 11, 2026. Proposals must be delivered to the City of Ann Arbor Procurement Unit at 301 East Huron Street, Ann Arbor, MI 48104 by February 18, 2026 by 2:00 p.m. (Local Time) in sealed envelopes containing one original printed proposal, one digital PDF copy on USB/flash drive, and cost proposals in a separate sealed envelope. Selection/negotiations are anticipated in February 2026, with City Council authorizations expected in March 2026. First purchase orders are targeted for April 2026, with all equipment deliveries required by the end of the second quarter 2026 (June 30, 2026) to support VPP construction completion by October 2026. Offerors must remain available for interviews and commit to certifying SEU-approved installation contractors on selected equipment.

Evaluation will use a weighted point system: Net unit price per system after tax credits (40 points), Equipment technical specs and performance (40 points), Service (10 points), and Procurement process ease (10 points). The City reserves rights to accept or reject any proposals, request additional information, award to multiple offerors, and determine final project scope. All proposals must include completed Attachment C (Non-Discrimination Declaration) and Attachment D (Vendor Conflict of Interest Disclosure) or face rejection as non-responsive.