Council hears solar feasibility for six city sites; staff urges focus on new construction

Consultants hired by the city presented a solar feasibility study showing technically viable, grid‑connected solar systems for six Urbandale facilities, but city staff recommended focusing future solar work on new construction rather than retrofitting existing buildings.

Sam Miller, senior consultant with QSTN, told the council his firm evaluated City Hall, the library, Fire Station 42, the police station, the rec hub and satellite storage facilities and developed two design options that generally prioritized rooftop arrays, with ground mounts or carports as alternates. “Grid connected, or grid tied on‑site behind the meter interconnected solar system was … feasible” at each site, Miller said. He added MidAmerican Energy’s current full retail net metering and rate structures make on‑site solar more favorable now.

City Manager David (last name not specified in transcript) summarized staff concerns after the presentation and recommended not investing significant capital to retrofit existing facilities at this time. “I don’t believe sitting here today that that's the right move for Urbandale,” David said, citing an accelerated and complex change in federal investment tax credit rules, the retrofit challenges of midlife roofs and structural or transformer constraints, and pressing capital needs including a police headquarters and fire station projects.

Why it matters: the study shows potential for large energy offsets at several sites and identifies where ground arrays or carports would be needed to approach near‑100% offset. But the council must weigh up‑front capital outlays against grant and tax‑credit timing, building lifecycle costs and other capital priorities.

Key findings and details - Scope: six city‑owned facilities were assessed. The study modeled rooftop maximized systems (Design 1) and combinations of roof plus ground/carport (Design 2). - Timelines: typical development and construction for a rooftop system is about 6 to 12 months from start to permission to operate, Miller said. - Utility treatment: MidAmerican Energy currently offers full retail net metering and favorable rate switching; staff noted those tariff provisions are in place under the utility’s current approval through July 2027 but could change, which would affect project economics. - Equipment and lifecycle: the consultant’s financial model used a 25‑year system life, included inverter replacements around year 12–15, and assumed ongoing annual operations and maintenance costs. - Limitations: City Hall’s existing transformer size limits how large…