Clean energy legislation and plans to retire more coal-fired power plants in the next 10 years have upended conclusions of the 2018 Lower Snake River Dam Replacement Study, according to an analysis by Energy GPS and commissioned by Northwest RiverPartners.
"Things have changed," RiverPartners' Executive Director Kurt Miller told NW Fishletter. "At this stage, we're deciding the future of the lower Snake River dams, our clean energy future, and also trying to avoid a recurrence of the 2000-2001 energy crisis. It's important to understand the details because it's a decision that will affect the whole region for many years."
The NW Energy Coalition—which hired Energy Strategies to complete the 2018 replacement study—said RiverPartner's analysis only validates the study's central finding: that the power and electric system services provided by the dams can be replaced by clean and renewable resources without reducing reliability. "In short, the Energy GPS critique confirms that the only question about replacing power and services from the dams is one of cost, not reliability," the coalition said in a written response.
But Miller says the critique shows that reliability is a big problem, and that the cost of replacing the power—if feasible—would be 80 percent higher. "If you talk to most of the regional energy planners, everyone's pretty much in agreement that we're headed for an energy shortage," he said.
Miller said RiverPartners wanted an analysis of the coalition study partly because it was cited in the draft report released by Gov. Jay Inslee's Lower Snake River Dams Stakeholder Engagement Process, and has become part of the dialogue in the debate over removing the dams. "We still hear the general public refer to that study as essentially proof that the lower Snake River dams aren't necessary," he said. "We're emphasizing its shortcomings because we want people to understand how things have changed, and the risks associated with going forward with those assumptions."
RiverPartners submitted the analysis in full as part of its comments to the draft report.
The NWEC study concluded the four dams could be replaced with a combination of conservation and renewable energy with little or no increases in greenhouse gas emissions and for a relatively low cost. It outlined several possible scenarios for replacing energy produced by the dams, and the coalition focused on a "balanced-plus" portfolio that would add 1,250 megawatts of new wind power, 250 megawatts of new solar, 160 average megawatts of energy efficiency and 500 megawatts of demand response. That option would cost an estimated $464 million a year and add about 360,275 tons of carbon to the environment—an increase of 1 percent.
Northwest RiverPartner's analysis complimented the methods used, but said key assumptions are already out-of-date and do not reflect the forecasted capacity shortfall. The NWEC study is more than 18 months old, and relies on assumptions from more than three years ago, Miller said. Since then, Washington passed the Clean Energy Transformation Act, which constrains options for replacing the dams.
"It's almost impossible to add new carbon-generation to the fuel mix right now because the West is moving away from carbon by mandate," Miller noted.
The study also assumes retirement of 2,300 megawatts of coal-fired power plants. A new resource adequacy study by the Northwest Power and Conservation Council indicates that between 4,500 and 6,000 megawatts of coal-fired power plants will go off line in the next decade, and about 20,000 megawatts of that will retire in the next 15 years.
"They're also talking about moving away from natural gas," Miller said. "It becomes politically undoable because of the concerns with carbon emissions."
NWEC's study also relies too heavily on new energy efficiencies, demand response and imported energy—much of the latter likely from new wind generation in Montana and Wyoming, Miller said.
It also underestimates transmission costs, assuming transmission freed up by Colstrip coal plant retirements will be used to deliver Montana wind, and that the Boardman to Hemingway line will integrate new solar energy from Idaho. Miller said those will be used to transmit power from other new sources that replace retiring coal. He said adding major new transmission is not only costly, but can be held up for decades. "There's no community in the country excited about new transmission lines," he said.
"On balance, the replacement portfolios presented by the NWEC study are either infeasible or significantly underestimate costs," the analysis states.
Cautioning that RiverPartners' analysis does not substitute the need for a more detailed study using more appropriate assumptions, the estimate adds new transmission costs and puts a price on carbon emissions to put the cost at $860 million per year, or $96 per megawatt hour.
"While the NWEC study is an ambitious project using industry-accepted models, it fails to present a feasible scenario where [lower Snake River dams'] capacity and energy are replaced with sufficient quantities of carbon-free resources," the analysis concludes.
Miller added that Energy Strategies—the consulting firm that completed the coalition's study—have since released a different analysis titled Western Flexibility Assessment that warns about energy shortages for the Northwest. That means most of the energy, transmission, energy efficiency and demand response counted on in its prior study on Snake River dam removal will be needed instead to replace lost coal-fired and other carbon-generating resources, he said.
In its written response, the NW Energy Coalition disputed that coal retirements and Washington's new clean energy law significantly change its study's conclusions about energy reliability.
And when it comes to costs, "we believe those changes actually tend to reinforce rather than undermine the study's findings," the coalition wrote.
"Since release of the study, new transmission resources have emerged as a result of earlier than expected coal retirements (Colstrip 3 and 4) and the Montana Renewable Development Action Plan, which identified added transmission capacity on existing lines. Additional transmission resources have also been identified in the West of McNary path that carries power to the Portland area."
It's also inaccurate for the Energy GPS analysis to assume there will be no more cost-effective demand response or energy efficiency resources available to help replace energy that would be lost if the dams are removed, the coalition says. If anything, many new opportunities are on the horizon for expanded conservation and demand response, such as new commercial building and appliance efficiency standards in Washington, and more automated home and building energy management systems.
The coalition cited a new study by Portland General Electric, the Bonneville Power Administration and other utilities demonstrating that grid-integrated water heaters can help redistribute energy load. And, NWEC noted, Washington adopted a requirement that all new water heaters must be equipped and ready for grid integration.
The coalition said it expects increases in both energy efficiency and demand response in the Northwest Power and Conservation Council's updated assessment in the 2021 Power Plan.
It also said technology and policy advances have already reduced the region's per-capita electric consumption by one-quarter since 1990, and that is likely to continue or accelerate as the region expands electrification.
Finally, the coalition said, the Energy GPS analysis does not consider the continuing decline in the cost of renewable resources, including wind and solar, since its study came out. And there have been advances in combining wind, solar and battery resources capable of providing dispatchable energy.
"We've seen in our region and others how rapidly new renewable resources can be developed to replace retiring fossil fuel resources," the NWEC response said. "And we are confident that the level of power replacement required of the region as a whole by Washington's Clean Energy Transition Act and other climate legislation is quite achievable."
"For these reasons," it said, "the NW Energy Coalition remains satisfied that the LSRD Power Replacement Study finding that energy and services from the lower Snake River Dams can be affordably and reliably replaced by a portfolio of clean energy resources is sounder and more relevant than ever."