Committee Upholds Law Requiring Utilities to Undergo Environmental Reviews for New Methane Gas Plants

Phoenix, AZ - In a hearing today, the Arizona Power Plant and Line Siting Committee voted 9-2 to deny Unisource Electric's (UNSE) request that the utility's planned 200 MW expansion of its Black Mountain Generating Station in Mohave County be exempted from obtaining a certificate of environmental compatibility (CEC), a process that requires weighing environmental impacts against the need for a power plant. The Committee's vote upholds the requirement that new gas-fired power plants must undergo environmental review via the CEC process. UNSE's argument would have set a dangerous precedent that would allow utilities to circumvent the rules, and would have created a loophole allowing gas plants to avoid review of their environmental impacts, such as emissions, noise, and water consumption.

On March 8, 2024, UNSE proposed building 200 MWs of new methane gas at its Black Mountain Generating Station. But UNSE made a legal argument that the Power Plant and Line Siting Committee and the Arizona Corporation Commission (ACC) did not have jurisdiction over the project, arguing that the Company does not need a CEC for the four-turbine expansion project because UNSE asserted the project should be considered four separate 50 MW power plants rather than one 200-MW power plant. UNSE's unprecedented and incorrect interpretation of the Line Siting Statute would have effectively exempted all new gas peaking plants from a regulatory process meant to evaluate their environmental impacts, and remove authority from the committee to be able to regulate Arizona's new peaking gas plants.

After coal, gas-fired peaker plants are some of the most expensive and heavily pollutingways to produce electricity, spewing toxic emissions that impact air quality, and disproportionately affect frontline communities. UNSE's expansion project follows a dangerous trend being seen across the country where utilities desperately clingto dirty energy by planning for more gas-fired plants despite affordable, near-term clean energy solutions like solar and storage.

In October, Mohave County set a moratorium on new solar projects, blocking them and making it easier than ever for gas-fired power plants to be built and expanded, and earlier this monthresidents protested the construction of a Mohave Electric Cooperative gas-fired peaker plant that would have been built in close proximity to a residential neighborhood. That plant did not require a CEC as MEC kept it just under trigger amount for siting at 98 MW.

"Gas-fired plants pollute our air, heavily consume water, impact lands, threaten our health, and harm the planet," said Sierra Club Grand Canyon Chapter Director, Sandy Bahr. "The Power Plant and Line Siting Committee made the right decision by denying UNSE's legal argument that would facilitate the creation and expansion of gas-fired plants without this important environmental review. The Company's attempt to create a loophole to avoid complying with checks and balances meant to weigh resource needs and decisions is dubious, and underscores UNSE's intention to recklessly double down on dirty energy."

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