Environmental groups and 18 state attorneys general are suing the Trump administration over its efforts to keep incandescent light bulbs on the market. They filed suit against the Department of Energy on Monday, claiming the agency's decision to allow sales of these hot-burning bulbs would hurt the environment and waste billions of dollars.

"The rule is harmful to the environment and also to consumers," said Mike Landis, litigation director at U.S. PIRG, one of the consumer advocacy groups that filed the suit. "In our view, this is an unlawful action the Department of Energy is taking. Once an energy-efficiency standard is set, the agency can't go back on that."

If the older lightbulb technology stays on store shelves, environmentalists say, the added emissions from their use by millions of consumers would be akin to keeping 128 coal plants running for a full year.

Get Breaking News Delivered to Your Inbox

The typical household light bulb today is about 15 times more efficient than it was a decade ago. Since Congress first legislated the issue in 2007, common bulbs have transformed from tiny space-heaters needing yearly replacement into cooler-burning globes that can last up to 25 years.

The requirements forcing bulbs to be efficient left out specialty light bulbs, including three-way bulbs, candelabra bulbs and recessed reflector lights of the kind often seen in kitchens. These specialty bulbs, which make up just under half of all light bulbs in America, were supposed to be covered by efficiency rules starting January 1, 2020. But the DOE recently moved to exempt them permanently — a move that would cost Americans an added $12 billion a year in added electricity costs and more frequent purchases of bulbs, according to the Natural Resources Defense Council.

"The industry's moved on"

If the Trump administration is intent on saving a technology that dates back to the 19th century, the lighting industry seems ready to let go. "It's too little too late," said Terry McGowan, director of technology at the American Lighting Association. "The industry's moved on."

"I see incandescents now that are higher in price than LEDs," he added. "I don't think price will bring back incandescent bulbs. A year ago, I wouldn't have said it, but I think it's happened."

Most consumers today choose longer-lasting, energy-saving bulbs, according to industry research firm Freedonia. Consumers might choose slightly cheaper, but more energy-intensive, bulbs if they're only planning to live somewhere for a short time, said Jennifer Mapes-Christ, an analyst with Freedonia.

"If you rent, you might be planning to stay for a year or two, in which case, why do you care if your light bulb lasts for 10 years?" she said.

In addition, she said, there's the perception of choice: "People bristle at being told what they're allowed to buy and what they're not allowed to buy."

Energy efficiency has gotten less attention in light bulbs than car engines, but the art of getting more bang from the same unit of energy has been a major reason U.S. emissions stayed flat for nearly a decade after the Great Recession.