Mainly, the problem is that "utilities are reluctant to reverse course on plans put in motion years ago or to backtrack on pledges to embrace renewable energy," Ari Natter reports for Bloomberg. "Plant closures that have been worked out under consent decrees to settle environmental lawsuits or in deals with state regulators also can’t be easily reversed."
Coal- and nuclear-powered plants have been closing in increasing numbers for years in the U.S., Natter reports. Nearly 40 percent of the capacity of coal-fired plants has been either shut down or designated for closure since 2010. And more than one-fourth of U.S. nuclear plants aren't profitable. Also, some utilities worry that Trump's use of emergency powers wouldn't stand up in court.
"Certainly I think right now utilities are considering going forward with retirement plans as is,” Richard Glick, a member of the Federal Energy Regulatory Commission, told Natter. "It’s pure economics. Gas prices are way down, renewable projects are getting much less expensive and they are beating other older technologies out in the markets."