Batavia council reviews first draft of Integrated Resource Plan; Brattle recommends natural-gas engines as capacity hedge

Batavia City Council on Oct. 20 reviewed the first draft of the city’s Integrated Resource Plan (IRP), a planning document prepared by the Brattle Group that outlines options to meet the utility’s energy and capacity needs over the next 20 years. Brattle recommended maintaining Batavia’s existing 55-megawatt supply contract with the Northern Illinois Municipal Power Agency (NIMPA) while soliciting quotes for locally sited reciprocating internal-combustion natural-gas engines as a hedge against rising capacity prices, and launching demand-side pilots such as time-of-use rates and smart-thermostat programs.

Brattle said the draft will be issued to the public on Oct. 31, will open a 60-day public comment period running Oct. 31–Dec. 30, and the city will hold a public meeting on Dec. 9. Responses to public comments and a revised final IRP are expected in early 2026 for the council’s consideration.

The plan and the presentation focused on the difference between energy and capacity and on a projected risk from rising capacity prices in the PJM market. “Batavia has had no or very limited load growth since 2018,” Brattle told the council, and, while the 55 MW NIMPA contract supplies energy, it does not always provide enough capacity at peak hours. The firm explained that capacity prices in the region could rise substantially in coming years and that a local, dispatchable generator could reduce Batavia’s exposure to those price spikes.

Brattle described three scenarios — base, high-price, and low-price — and compared technology options. The consultants said reciprocating natural-gas engines (referred to in the presentation as “resips”) carry a high capacity accreditation in PJM and so provide greater capacity value than standalone solar, wind or battery storage. “One of the suggestions from our side is solicit for actual quotes of what [a natural-gas] asset may cost,” the consultant said, adding that engines in the market most commonly are in the roughly 10-megawatt size range.

The presentation also noted tradeoffs: solar and batteries have lower capacity accreditation (Brattle cited storage accreditation near 40–50% and solar lower still), and siting, land requirements, noise and conversion of engines to other fuels in the long term are practical considerations. Brattle said resips can potentially be retrofitted for other fuels in the future, but that hydrogen and similar alternatives remain costly at present.

Brattle recommended a near-term work plan: (1) publish the draft to start public comment; (2) solicit requests for information/quotes (RFI/RFQ) for generation and other resources in the next five years; (3) pilot demand-side programs (time-of-use rates and smart-thermostat incentives); and (4) run follow-on studies (infrastructure, cost-of-service, and rate design) before final decisions.

Council members raised practical questions during the workshop: how large a resip would be (consultants said the market commonly shows units around 10 megawatts and cited Geneva’s set of ~6 MW engines as a local comparison), where backup generators would be sited given limited vacant land, and how the public’s preference for renewables would factor into decisions. A council member noted a perceived undercount in the draft of local electric vehicles and asked that Brattle incorporate or reconcile local permit and observational data for EV adoption.

Brattle acknowledged public concerns about local combustion-based backup generation near homes and encouraged the city to use the RFI process to test alternatives and costs. The consultants also underscored that the IRP is iterative: the draft is an initial plan that will be revised as the city completes infrastructure and rate studies and receives public comment.

The council and staff set the schedule for public distribution and outreach: the draft materials and a public-facing slide deck will be posted and mailed to residents, a public meeting will be held Dec. 9, and the public comment period will close Dec. 30. Brattle said the team will compile comments and responses and return an amended IRP for council review in early 2026.

The discussion also touched on state-level timing and markets. Brattle said Illinois legislation imposes timing constraints for public notice, and discussed PJM market dynamics and the possibility that capacity prices might moderate if PJM clears interconnection backlogs and new capacity enters the market — while acknowledging that data centers and other load growth could push capacity needs in the other direction.

Next steps: publication of the Oct. 31 draft and the Dec. 9 public meeting, follow-up RFIs/RFQs and pilot demand-side programs in the first five-year window of the IRP, and subsequent infrastructure and rate studies prior to any council decision to acquire local generation.