To get a sense of how monumentally difficult it would be to wean Minnesota off fossil fuels, one only needs to look at climate change politics in St. Paul.

On Monday, Gov. Tim Walz called global warming an “existential threat” in need of an “immediate” response and proposed the state’s electric sector rid itself of coal and other greenhouse gas producers … over the next 31 years.

For those counting, that deadline is toward the later end of what would be Walz’s eighth term in office. Still, 2050 has been at the center of the debate over how fast the state can politically and logistically move toward clean energy. It’s also turning into something of a rallying cry for Democrats around the country, like the $15-per-hour minimum wage but for climate change.

Republicans, who have a majority in the state Senate, were largely skeptical of Walz’s energy plan on Monday and have already painted it as an unrealistic mandate that would raise energy bills for homes and businesses. But Walz, joined by political allies at the state Capitol, told reporters the strategy was necessary and doable as scientists predict dire consequences of Earth’s rapid warming.

“This is not just aspirational,” Walz said. “This is operational.”

Can it be done?

Besides setting a hard deadline for utility companies to provide carbon-free power by 2050, Walz’s plan, introduced in the Legislature by Rep. Jamie Long, DFL-Minneapolis, comes with some new regulations and legal changes.

First, it would bar utility companies from adding new fossil fuel power — or replacing existing fossil fuel sources with new ones — unless they can show it’s necessary to “ensure reliable, affordable electricity,” according to Walz’s office. This would be a stricter standard for state regulators, who currently do take clean power into consideration when approving energy projects. Next, Walz’s legislation looks to increase energy efficiency for utilities and customers, including by expanding a program that helps homeowners save power.

Minnesota is already moving toward clean energy quickly in some respects. A 2007 law signed by Gov. Tim Pawlenty required utilities to get at least 25 percent of their power from renewable energy sources by 2025, a goal the state achieved at the end of 2017. In fact, between 2005 and 2016, greenhouse gas emissions coming from the state’s electricity sector fell by nearly 30 percent.

The state’s largest energy provider, Xcel Energy, announced last year it plans to go carbon-free by 2050 on its own, with a mix of energy that includes a fair amount of nuclear power. Some research suggests the 2050 deadline is possible across the state thanks to factors like new technology, dropping prices for wind and solar and aging coal plants that are set to retire anyway.

But there are headwinds. Minnesota’s power sector is made up of a complex mix of for-profit utility companies and smaller nonprofits run by cities or cooperatives. About 70 percent of the state’s power is distributed by the for-profit companies, Steve Kelley, Commissioner of the Department of Commerce, told MinnPost.

One of those private utilities, Minnesota Power, ran on 95 percent coal as recently as 15 years ago. But the company has since retired seven of its nine coal units and has increased its share of renewable energy to 30 percent. Even so, the utility — which serves a region that includes Duluth, International Falls, Grand Rapids and Little Falls — has only committed to reach 45 percent renewable energy by 2025. Kelley said some small, rural cooperatives with fewer customers also might be more hesitant to switch to renewables.

Can it be done politically?

Walz is not the first to propose stricter deadlines for carbon-free energy in the state. Long, the DFLer from Minneapolis and Sen. Nick Frentz, DFL-North Mankato, introduced their own 2050 bill earlier this year with just a sprinkle of GOP support, and Frentz introduced a bill in 2017 for 50 percent renewable power by 2030 that did not pass.

Walz’s proposal brings extra political heft, but his bill has some key differences. Walz’s plan does not set new targets between now and 2050 for utility companies to meet along the way, giving those power suppliers more wiggle room on the path away from fossil fuels. Walz said the change “shows the good faith effort that we are partnering with our utilities and our energy generators.”

A statement issued by ALLETE, the parent company of Minnesota Power, did not endorse the plan, but thanked Walz for the “flexibility” in it. “We especially appreciate that the proposal is not a “one size fits all” approach, taking into account utilities across the state are different in size, energy supply portfolio and the customers they serve,” says the statement, signed by Al Hodnik, ALLETE’s chairman and CEO, and Bethany Owen, the company’s president.

The stronger standard for new fossil fuel production has similarities to a bill introduced last year by Sen. David Senjem, R-Rochester, and cosponsored by a slate of Republicans, Kelley added. And Walz included measures to promote high-wage, union jobs for construction and operation of energy infrastructure, including by allowing power companies to recoup costs of those hiring efforts from their customers.

Nationally, efforts to limit fossil fuels in the electric sector have gained considerable momentum. Hawaii and California have 2045 deadlines for total renewable energy use in their electric sectors and Washington state appears poised to follow. Wisconsin Gov. Tony Evers also proposed a 2050 target on Friday, and Democrats in the Illinois Senate this year proposed a 2030 deadline for its power sector to be carbon free.

But Walz’s legislation likely still faces an upward climb in St. Paul. David Osmek, the Mound Republican who chairs the Senate’s Energy and Utilities Finance and Policy Committee, told MinnPost he was concerned renewable energy isn’t reliable enough during severe cold and doesn’t want energy mandates to burden Minnesotans with higher costs when the state only emits a small fraction of global emissions. Solutions must come from talks that include other countries with high emissions, he said.

Pinning down the cost of a 2050 deadline for carbon-free energy is difficult. Kelley said the Commerce Department did not have an estimate for the price of Walz’s plan. And various research and partisan organizations have said deep cuts to greenhouse gas emissions might either raise bills or save households hundreds of dollars per year.

“Nobody debates whether we should have a cleaner environment,” Osmek said. “The problem is how much are we going to spend?”

Walz, ever optimistic, told reporters Monday was the start of Minnesota’s path to a complete overhaul of its power sector, even if the end date is far in the future. “I hope someday, when the story is written, that March 4th of 2019 is when this turned and when Minnesota took its rightful place, as it always has been, of being innovative, solving problems and creating a better, more equitable and cleaner future,” he said.