Planning commission recommends approval of Platte River’s Rawhide turbine permit after split vote

The Larimer County Planning Commission on Feb. 12 recommended that the Board of County Commissioners approve Platte River Power Authority’s Article 10.41 permit application to add five aeroderivative natural‑gas turbines and related infrastructure at the Rawhide Energy Station near Wellington, by a 5–4 roll call vote.

Why it matters: The turbines are designed to provide 200 megawatts of dispatchable capacity intended to back up large additions of wind and solar in PRPA’s resource plan. Supporters say the project will help the utility retire a coal-fired “Unit 1” by 2029 and keep electricity reliable during extreme weather; opponents say adding new gas infrastructure locks in additional greenhouse‑gas emissions and threatens local air quality.

Platte River’s proposal and staff recommendation Platte River Power Authority (PRPA) asked for a 10.41 review to install five new GE LM6000 aeroderivative gas turbines (about 40 MW each), an ammonia storage tank, wastewater and water tanks, substation bus work and transmission upgrades, and construction staging areas. PRPA representatives told the commission the turbines are intended to be a flexible, fast-start resource to support intermittent solar and wind and to facilitate the retirement of Rawhide Unit 1, a coal unit the utility expects to retire by the end of 2029.

County planning staff summarized the application and said the project would occupy roughly 30 acres of the 4,590‑acre Rawhide site with another approximately 32 acres used for laydown, for a total of about 62 acres affected. Staff reported referral comments from 10 agencies and said the Colorado Department of Public Health and Environment (CDPHE) will handle the state air permitting (Title V/major source) process. Staff recommended approval subject to 32 potential conditions the staff report describes as addressing air quality, noise, hazardous materials, engineering, and wildlife/vegetation protections.

Public testimony and referral responses The hearing drew heavy public comment: staff said the county collected 51 public comments through its public input tool by 4 p.m. the day of the hearing. Speakers in favor included PRPA board members and municipal utility officials who said the turbines will preserve reliability while the utility adds renewables. PRPA staff and consultants presented the utility’s integrated resource planning (IRP) process, asserting the selected site is suitable, the machines are more flexible and efficient than current frame units, and that modeled emissions comply with regulatory thresholds.

Opponents—environmental groups, independent experts, and residents—urged denial. Key concerns raised during public comment and in letters included: the project expands fossil‑fuel infrastructure rather than prioritizing storage and distributed resources; PRPA’s IRP and ELCC (effective load carrying capability) assumptions undercount renewable reliability; the application lacks independent third‑party review (several commenters asked for an NREL review); and that emissions and public‑health impacts could increase during an operational overlap while Unit 1 is still operating.

Questions from commissioners and applicant responses Commissioners pressed PRPA on: how often the turbines would operate (PRPA said “as needed,” varying by market and system conditions); expected lifetime (PRPA said ~30 years, with potential for upgrades); conversion to hydrogen (PRPA said conversion is technically possible but depends on hydrogen production, transport and storage infrastructure); potential short‑term emissions during overlap testing with Unit 1; and the project’s financial impacts on wholesale rates (PRPA cited a forecast wholesale rate increase of roughly 6.3% in coming years tied to a broad portfolio of investments, and said portfolios that avoided new gas plants would be materially more expensive).

A number of technical issues drew extended questioning: the choice of aeroderivative turbines rather than combined‑cycle plants (PRPA said aeroderivatives provide the fast start/stop flexibility needed to back up renewables); how ELCC values were used in the IRP; whether joining the Southwest Power Pool (SPP) changes resource adequacy obligations; and how state air permitting and CDPHE modeling will interact with county review. PRPA and staff said CDPHE will issue a state air permit and that the county’s 10.41 conditions would guide later technical review.

Vote and formal action The commission’s formal motion—moved by Commissioner Connor Duffy and seconded by Commissioner Eggleston—recommended Board of County Commissioners approval of PRPA’s 10.41 application subject to the staff‑recommended conditions of approval. Roll‑call votes recorded on the motion were: John Weiss (No); Shelby King (No); Jordiana Barrack (No); Lisa Chalet (No); Connor Duffy (Yes); John Slutsky (Yes); Nick Cassidy (Yes); Commissioner Eggleston (Yes); Patrick Rowe (Yes). The motion passed 5–4. The county’s final decision will be at a future Board of County Commissioners hearing.

Conditions, technical review and next steps Staff noted the project would be subject to a subsequent technical review if the Board approves the 10.41 recommendation. The staff report listed conditions addressing air‑quality controls, hazardous‑materials planning, construction traffic and erosion control, wildlife avoidance and buffering (including consultation with Colorado Parks and Wildlife for active bald‑eagle nests), and post‑construction reclamation and monitoring. County staff said any required permits, easements and state air permits must be secured before construction begins; technical review would include engineering details, construction schedules, and final mitigation measures.

What the commission heard from proponents and opponents Supporters—including municipal utility staff and some community stakeholders—argued the project is needed to preserve reliability as PRPA adds up to 760 MW of renewables and to enable Unit 1’s retirement. PRPA also emphasized its community‑owned, nonprofit model and its board governance.

Opponents pressed for greater third‑party technical review of the IRP assumptions (including ELCC and reserve margin values), said the application risks locking in fossil infrastructure, and urged the commission to require PRPA to pursue alternatives such as deeper investment in distributed resources, storage, and a formal independent review of the IRP.

Outlook The Planning Commission recommendation will be forwarded to the Board of County Commissioners, which holds the final decision. County staff and PRPA acknowledged additional state and local permitting steps remain, including the state air permitting process. If the Board approves the 10.41 permit, the project will enter technical review, where final engineering, permitting, and mitigation plans will be developed and enforced.

Ending The commission’s split vote reflected sharply divided views about tradeoffs between near‑term emissions impacts, long‑term decarbonization pathways, and local reliability. The Board of County Commissioners will consider the recommendation in a future land‑use hearing where PRPA and community stakeholders can present final details and technical permit conditions.