Navitus presents wastewater‑to‑RNG plan; board questions project after RG&E cost increases

Bob Wimmer, a representative of Navitus, outlined a proposal on June 4 to convert digester gas at the Webster wastewater treatment plant into renewable natural gas (RNG), explaining the treatment chain, market value and updated cost estimates.

Wimmer described digester gas as about "60 to 70% methane" and said the plant currently consumes roughly 45–47% for on‑site heating, flaring the remainder. He walked the board through processing steps — moisture removal, activated‑carbon contaminant scrubbing, and CO2 removal with membrane separation — and said the process yields an RNG product that can meet local distribution quality.

Wimmer reported a carbon intensity score of negative 22 for the plant conversion, which he said indicates the facility would reduce more greenhouse gases than it produces. He gave a projected annual production figure of about 29,000 MMBtu, which he equated to roughly 300 households' annual natural gas use for the portion of gas not currently used on site. "So if you equate that to household use, that's about 300 households of natural gas use here in the Webster area," he said.

Navitus also presented a revenue range for environmental attributes and offsets of roughly $10 to $17 per MMBtu, which produced a potential annual revenue estimate of about $290,000 to $493,000 before updated costs. Wimmer told the board that RG&E had revised its interconnection Capital Expenditure estimate upward — "the CapEx cost has increased, from 1.2 to about $1,600,000" — and added roughly $85,000 to annual O&M. He said those changes reduced projected net revenue substantially.

Because of the revised RG&E terms, Wimmer said Navitus paused active project work the morning of the workshop while it ran alternatives. "So this morning, with the new information and, I stopped all work on the project this morning," he said. Navitus told the board it could evaluate tube‑truck (compressed tanker) options and report back in about two weeks.

Board reactions were sharply divided after the updated costs were disclosed. One board member called for a vote to terminate the RG&E contract and asked other members to state whether they supported moving forward under the current terms. A separate board member urged urgency and better internal communication so the board could consider a decision at its next meeting.

Navitus and two tax consultants (Witham and MSC Consulting) told the board that the project likely qualifies for the Clean Energy Tax Credit under the Inflation Reduction Act, with consultants estimating a potential credit between about $6.8 million and $8.0 million that would substantially reduce the project’s net capital cost. Wimmer said equipment has long lead times (quoted at about 56 weeks), so procurement timing could affect tax‑credit continuity.

No formal contract approval or bond resolution vote occurred at the workshop. Navitus said it would update the final slide deck and return with refined cost figures and alternatives for the board's consideration.