Sewer Authority Minosa continues public hearing, authorizes manager to negotiate solar-plus-storage PPA with Coldwell Energy

The Sewer Authority Minosa on April 13 opened a public hearing on a proposed solar-plus-battery project to be sited inside the SAM wastewater treatment plant and authorized the general manager to continue negotiations on a power purchase agreement with Coldwell Energy and return a proposed PPA for board consideration. The board also authorized reimbursing Coldwell up to $10,000 for SQA-preparation work if SAM does not enter the PPA, and continued the public hearing to April 27, 2026.

Staff told the board the project would require no upfront capital from SAM and, in the current proposal, would deliver a mix of rooftop and carport solar plus a two-hour battery sized to serve roughly 25% of the plant’s current electricity use. "The way it works is that private owners can invest their own capital in a design build delivery, own the system and charge SAM for the beneficial energy," a staff presenter said, describing the 25‑year PPA with a 3% annual escalator included in the staff materials. Staff estimated the project would produce about $3 million in savings over 25 years and about $20,000 in net savings annually to SAM.

Presenters emphasized federal tax‑credit timing as a driving factor. "Just like it says, physical work—you have to be starting physical work on site," Jordan Comtock of Coldwell Energy said, describing the IRS ‘‘physical work’’ test the company plans to use to secure investment tax credits. Comtock said qualifying actions can include specific on‑site activities or off‑site work that is dedicated to the project and cannot be reused on another job.

Design and siting have changed since the RFP stage. Staff and the vendor described three design iterations that removed off‑site ground arrays and focused the system inside the plant fence—rooftop arrays and three steel carport structures—and identified several candidate battery pads near existing electrical rooms or transformers. "We are proposing lithium iron phosphate batteries," a consultant working with the vendor said, noting UL certification and the chemistry’s lower propensity to the combustion behaviors seen in other lithium chemistries.

Residents and technical commenters voiced support for the solar portion and cautioned on battery siting and operational risks. Tristan Glenn Wright, who described himself as a nearby resident and an experienced solar/battery engineer, said LFP chemistry is safer than some alternatives but cautioned "LFP can still be incited into thermal runaway" if defective cells occur and urged care placing batteries near fuel tanks and in flood-prone areas. Other speakers asked for clearer design drawings, long‑term vegetation and maintenance responsibilities for carport locations, local permitting coordination with Half Moon Bay, and confirmation of tariff and domestic‑content compliance.

Board counsel and staff noted environmental review steps remain. Staff recommended drafting categorical exemptions (class 1 and class 3) and vetting them with the city and the state clearinghouse, while counsel advised site‑specific vetting before a final determination. The board voted to authorize the general manager to expediently complete negotiations, to reimburse the vendor up to $10,000 for SQA work if a PPA is not executed, and to continue the public hearing to April 27 to allow staff and the vendor to refine designs and documentation.

Next steps: staff will return to the board with revised SQA documentation, updated siting drawings and a proposed PPA for consideration at or before the April 27 meeting. No final contract was approved at the April 13 meeting.