The Trump administration is preparing a plan that could require electric grid operators to keep coal and nuclear power plants open. It's a move the administration says will bolster national security but that critics say will drive up the price of electricity and slow the conversion to green power.

Under a preliminary plan, first reported by Bloomberg Friday, the Energy Department could use its emergency power under two federal laws to require utilities to buy some of their power from coal and nuclear-powered plants that are threatened with closure.

White House spokeswoman Sarah Sanders said Friday that President Trump believes "keeping America's energy grid and infrastructure strong and secure protects our national security… Unfortunately, impending retirements of fuel-secure power facilities are leading to a rapid depletion of a critical part of our nation's energy mix, and impacting the resilience of our power grid.”

Underlying the plan to support the beleaguered coal and nuclear industries is the theory that they provide more stable and resilient sources of electricity than renewable sources like wind and solar power and than natural gas.

That’s a contention that is hotly disputed by the green power producers, oil and gas companies and the regulators who oversee many of the nation’s power systems — which have been rapidly shifting to cleaner sources of electricity.

Coal industry leaders and some utilities praised the Trump administration's move on Friday.

Betsy Monseu, CEO of the American Coal Council, an industry group, called the potential support from Trump's Energy Department "critically important.” Without it, she said, “More coal and nuclear plants will be prematurely closed and that would have impacts to the future reliability and resilience of the grid.”

Coal and nuclear are considered “baseload” fuels, meaning they can supply a consistent amount of power for long periods of time, with abundant fuel stored at plants where it will be turned into electricity.

Charles Jones, CEO of the Ohio-based utility FirstEnergy, said preserving coal and nuclear plants “is the right thing to do for the industry, the electric grid and our customers.”

In a memo circulated in advance of a National Security Council meeting Friday, Trump officials discussed the possibility of invoking two rarely used statutes to support coal and nuclear. The Energy Department could act, according to the memo, under the Federal Power Act and the Defense Production Act, the latter used by President Truman to support the steel industry.

The memo envisions requiring electricity purchases from coal and nuclear sources for a two-year period, which the Energy Department would use to study shortcomings in the U.S. electricity system. Critics have said that wind and solar power are inconsistent, providing less energy when the sun is down or the wind isn’t blowing. Even natural gas supplies can be disrupted by supply-line breakdowns, they suggest.

An array of groups attacked the Trump administration's proposal Friday, saying it would prop up one of the dirtiest and most expensive sources of power — coal — while costing customers more money and putting more climate-warming greenhouse gases into the atmosphere. Critics also suggested Trump has political motivations for propping up outmoded technologies, because coal company executives have been among his big financial backers.

“I eagerly await the administration’s regulations protecting pagers, fax machines, and Blockbuster,” tweeted former California Governor Arnold Schwarzenegger, lumping coal and nuclear with other outdated products.

Some legal experts questioned whether the Energy Department could invoke the Federal Power Act, saying the law traditionally has been used to respond to hurricanes, blackouts and other disasters. Several critics suggested that they would challenge the action in court, if necessary.

The opposition crossed a wide spectrum of industries.

Electricity Consumers Resource Council President John Hughes, representing big industrial power users, said the Trump concept would “prop up uneconomic coal and nuclear plants” and “increase the price of electricity to businesses and consumers, resulting in a substantial loss of U.S. manufacturing capacity jobs.”

The Sierra Club, in a statement, depicted the support for coal and nuclear power as a “bail out [for] wealthy fossil fuel executives.” Mary Anne Hitt, director of the environmental group’s Beyond Coal Campaign, predicted the Energy Department action would fail “because it is out of touch with reality and out of step with the law.”

A representative of the American Wind Energy Association, Amy Farrell, said that the “orderly retirement” of legacy power plants did not create the kind of emergency requiring special action by the Trump administration. She said that conclusion had been reached by “independent energy regulators, grid operators and other experts.”

Neither the Energy Department nor the White House gave an indication of when they might move ahead with the strategy.