Get Full Government Meeting Transcripts, Videos, & Alerts Forever!
Get email alerts on the Wastewater Infrastructure topic
No spam. Unsubscribe anytime.
Council hears wastewater solar study and bio solids plan; staff to repurpose solar borrowing for plant repairs
Summary
Consultants told the Fort Atkinson City Council that a proposed solar array at the wastewater treatment plant would have long payback periods and significant interconnection costs; the same consultant recommended phased repairs for bio solids equipment. Council signaled staff would reallocate previously borrowed solar funds to plant rehabilitation.
Consultants from Donahue & Associates told the Fort Atkinson City Council on June 16 that the city’s wastewater treatment plant could host a solar array but that the economics and site costs make the project marginal as originally scoped.
At a presentation led by wastewater engineer Nathan Cassidy, electrical engineer Caram Beerman described three alternatives: a 300 kW array (about 504,000 kWh/year, roughly 1 acre, estimated gross cost ~$2.9 million and net ~$2.0 million after potential incentives), a 900 kW array (about 2.7 acres, greater generation but ~30% exported to the utility) and a 900 kW array paired with batteries. “A 300 kW system … offsets about 15% of the energy uses,” Cassidy said, adding that payback periods for the options exceed 20 years and that interconnection costs and a long duct bank across the facility drive much of the price.
Donahue’s report also recommended a conservative approach to batteries: the firm estimated that even sizeable battery storage would increase the yearly energy offset by only a few percentage points while lengthening payback. The consultant recommended the 300 kW option if the city pursued solar, largely for its smaller scale and lower upfront cost, but noted the payback exceeded expected asset life.
The council then heard Donahue’s bio solids facility plan. The consultant said unit processes currently have capacity for projected flows but that many bio solids-handling components are aged or deficient. The assessment identified pumps, thickeners, centrifuge feed pumps and blower equipment among items needing replacement or rehabilitation. Donahue presented a phased implementation plan that staggers work across short-term (2027–2028), mid-term (2029–2031) and later priorities tied to condition assessments and operational risk.
Director of Public Works Zach said the city had borrowed $1.5 million in 2024 for a solar project; after the presentation staff and the city’s financial adviser recommended not moving forward with the full solar project as scoped and instead using the borrowed funds to accelerate near-term wastewater repairs and prioritized replacements identified in the bio solids plan.
Why it matters: the wastewater facility supplies essential services and requires capital and ongoing maintenance. The consultant’s findings suggest modest carbon and utility-cost benefits from a limited solar installation but substantial near-term capital needs to maintain treatment and bio solids handling. The council did not enact a purchase order for solar; staff will bring specific repair actions and funding proposals in upcoming meetings.
Provenance: Topic first introduced at SEG 101 and discussed through SEG 294 (solar study) and resumed at SEG 455 through SEG 725 (bio solids study).
