The 2020 closure proposal is a kind of compromise proposal — PGE is asking to be allowed to install less expensive equipment that would reduce emissions less. The proposal will require buy-in from ratepayer groups and the approval of environmental regulators.

The Oregon Public Utility Commission (PUC) would have to approve closing the plant in 2020, because the shorter time frame for amortizing the emissions control investment could lead to increased rates for purchasers of electricity. And the Environmental Quality Commission would have to approve the proposal for less stringent emissions controls.

The Boardman plant has also been targeted by environmental groups as a big emitter of carbon dioxide, which contributes to global warming. PGE spokesperson Steve Corson acknowledged that the company faces a certain amount of financial risk if carbon comes to have price under future greenhouse gas controls.

Corson said PUC could sign off on the 2020 proposal first half of this year, while the EQC, which is the rule-making body for the Department of Environmental Quality (DEQ) would have its say toward the end of the year. If agreement on an alternative plan can’t be reached, PGE will continue to seek approval for installation of all required emissions controls and continued operation of the plant through 2040.

PGE also outlined an alternative to outright closure in 2020: The plant could be adapted to burning a still-in-development coal-like fuel made from wood or plant material. That could help PGE comply with a state law passed in 2007 that requires investor-owned utilities to generate 25 percent of their electricity from new renewable sources by 2025. Known as “renewable portfolio standard,” it is spurring big growth in wind, as well as research and development of wave, geothermal, and biomass sources.

Though any change is years away, Local 125 Political Affairs representative Marcy Putnam said the union is seeking to meet with PGE to discuss impacts. PGE is a major employer in sparsely-populated Morrow County, with not only Boardman but also the Coyote Springs natural gas electricity generating plant.

With 10 years notice, members will have a lots of options, Corson said.

For one, PGE is proposing construction of a new 300 to 500 megawatt natural gas plant at Carty Reservoir, adjacent to the Boardman plant. That is driven by increased demand — and the need for “wind-chaser” generation to compensate for the intermittent nature of wind generation. The plant would be similar to the 400-megawatt plant at Port Westward in Clatskanie.