If wind turbines and solar panels are the celebrities of the clean energy revolution, then energy efficiency is its workhorse.

U.S. electricity demand has stagnated in recent years, as building codes have become more stringent and more efficient appliances like LED lightbulbs have become commonplace. Americans used less electricity in 2017 than they did a decade earlier.

That has helped spur a dramatic decrease in carbon dioxide emissions from power plants, the engine of U.S. emission reductions in recent years. The Department of Energy estimates power plant emissions fell 28% between 2005 and 2017. Lower electricity demand was responsible for roughly half the reduction, or about 654 million tons of cut carbon. Renewables, by comparison, cut 316 million tons of emissions.

Whether those efficiency improvements continue is now a matter of increasing contention between DOE and climate hawks. DOE is moving slowly to upgrade existing standards, has proposed a new waiver for test procedures and narrowed the definition of lightbulbs subject to new efficiency standards.

Trump administration officials say they support energy efficiency and argue the new rules are aimed at streamlining federal standards. But greens say the moves have the potential to subtly erode efficiency gains, cost consumers billions of dollars and leave America facing a steep climb toward the emission reductions targeted by the Paris climate accord.

An efficient product produces energy savings over the decade or so it is in use, said R. Neal Elliott, senior director of research at the American Council for an Energy Efficient Economy. But when efficiency standards are not enhanced, the lost savings gradually accumulate over the years. The Natural Resources Defense Council estimates the lost energy savings associated with a narrower lightbulb standard amount to 25 coal plants’ worth of additional electricity.

“You’re not going to see it in year one, but in year 10 it will be like, ‘What the hell happened here?’” Elliott said.

Congress mandates energy efficiency standards for appliances. Existing standards are required to be reviewed every six years. But, as of May, DOE had missed the legal deadline for reviewing 17 product standards, according to the Appliance Standards Awareness Project, which advocates for energy efficiency measures.

DOE did not respond to a request for comment.

“One of the big foundations of our climate response have been these standards over the last 35 years,” Elliott said. “And what is now at risk is the continuing [of] that virtuous cycle of modernizing those standards.”

A second fight is forming over waivers granted for testing procedures. DOE now offers interim waivers to companies whose appliances do not conform to testing protocols, which ensure products meet federal efficiency standards. But the current system has drawn industry complaints, with companies saying the process takes too long.

Under DOE’s proposal, a company could receive an automatic waiver for a proposed test if the department fails to respond to an application in 30 days. It also calls for a six-month grace period. DOE would not take action against a company for at least a half-year in the event it later decides to revoke the waiver. Environmental groups and some companies have criticized the proposal, saying it opens the door to cheating (Energywire, June 13).

But the biggest fight is over lightbulbs. Earlier this year, DOE said it was scaling back the number of lightbulbs that would be subject to increased efficiency standards next year.

Industry groups, which support the move, say Congress never intended to regulate candelabra, reflector bulbs and round globe bulbs as general service lamps, which will be subject to a new 45-lumen standard as of Jan. 1, 2020. And they argue more efficient LEDs are already taking over the market, eliminating the need for federal regulation.

“The lighting revolution is nearing its end,” said Clark Silcox, a lawyer for the National Electrical Manufacturers Association, which represents lightbulb makers.

Environmentalists argue just the opposite. NRDC says the proposal is illegal because it effectively rolls back the standard. The group estimates the extra electricity will add $12 billion to consumers’ electric bills.

“The federal government not taking action on this slows down our progress when we should be accelerating our progress and need every bit of energy savings we can get,” said Lauren Urbanek, a senior energy policy advocate at NRDC.

In many ways, the lightbulb fight encapsulates the wider fight over energy efficiency.

Energy efficiency could make up half of the emissions reductions needed to satisfy the Paris Agreement’s 2025 target, according to a study by the American Council for an Energy-Efficient Economy. Expanding efficiency programs further could close another third of the remaining gap.

Last year underlined the dangers of backsliding on energy efficiency. Fueled by a hot economy and extreme weather, American electricity demand increased by roughly 2% in 2018, the first increase since 2014. Increasing demand helped push power plant emissions up for the first time since 2013. They rose 1.1% on the year.

Reprinted from Climatewire with permission from E&E News. E&E provides daily coverage of essential energy and environmental news atwww.eenews.net.