Daniel Acker/Bloomberg

The Lowly Lightbulb Outshines Solar and Wind on U.S. Power Grids

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Utility and power grid managers in the U.S. are learning that the best way to cut carbon emissions and improve efficiency is the easiest: Just change your lightbulbs.

The nation’s largest grid, serving more than 61 million customers from Washington to Chicago, is revising its demand forecasts after recognizing that better lighting has undercut its projections. Swapping all of Thomas Edison’s incandescent lightbulbs with lamps containing light emitting diodes, or LEDs, would save enough electricity to power 20 million American homes, according to the Energy Department.

Americans’ energy-conservation efforts, from switching bulbs to upgrading washing machines and air conditioners, have done more to reduce carbon emissions than the increased use of solar, wind and natural gas, according to consultant Wood Mackenzie Ltd. Efficiency can help meet half of the emissions cuts sought under President Barack Obama’s Clean Power Plan, the American Council for an Energy-Efficient Economy said.

“It’s a total bulb revolution,” Prajit Ghosh, director of power and renewables research at Wood Mackenzie in Houston, said Aug. 10 by phone. “The decline in load growth from both macroeconomic factors and energy-efficiency gains is by far the biggest reason carbon emissions fell. At least for the last five years, a majority of these savings came from lighting.”

Better Bulb

A switch from the incandescent lamps, which were introduced in the 19th century, was prompted by the Energy Independence and Security Act of 2007 that required lighting to become 25 percent to 30 percent more efficient by 2014 from 2008 levels.

Lighting accounts for about 5 percent of a home’s energy budget and switching to more efficient bulbs is one of the fastest ways to cut those costs, according to the Energy Department. LEDs use 75 to 80 percent less energy than incandescents and last 25 times longer.

LEDs will account for 83 percent of the lighting market share by 2020 and almost all of it 10 years later, the Energy Department says. The cost of the bulbs has fallen by more than 85 percent in six years, according to ACEEE, a Washington-based non-profit that promotes conservation. Bulbs are now available for less than $5.

Use of the new bulbs is catching on. In February, the Super Bowl became the first National Football League championship played under LEDs. Ikea Group, the worldwide furniture retailer, said Aug. 10 that it will carry only LEDs starting next month and that they would be sold at the lowest price on the market.

Grid Impact

PJM Interconnection LLC, which manages the largest U.S. grid, will for the first time include the effect of more efficient light bulbs and appliances in its long-term demand outlook, Tom Falin, manager of resource adequacy planning, said at the grid operator’s headquarter in Valley Forge, Pennsylvania.

The forecast for peak demand, a reflection of supplies needed on the hottest day of the year, will decline in 2016 from this year’s level using a new model, he said. Forecasts will be cut by about 4 percent each year through 2031 in the 15-year outlook.

“Within the last three or four years, our performance model has not been performing as well as it had been,” Falin said. Electricity demand no longer has the same responsiveness to economic growth that it had, he said.

PJM isn’t alone in recognizing the new efficiency. The Texas grid operator revised demand forecasts as growth lagged behind the economic rebound, easing concern about blackouts in the country’s biggest energy-consuming state.

More Savings

Duke Energy Corp. and American Electric Power Co. say energy efficiency helped them reduce carbon emissions. Exelon Corp. said higher demand from the improving economy in Chicago, Baltimore and Washington is being partially offset as consumers become more efficient. DTE Energy Inc. sees flat growth over the next few years compared with earlier projections of a 0.5 percent increase.

U.S. power demand reached a record 10.66 billion kilowatt-hours a day in 2007, a level not matched eight years later, according to the U.S. Energy Information Administration. Carbon dioxide emissions from electricity producers declined by 15 percent to 2.17 billion metric tons in 2013 from 2005, the agency said.

Lower demand forecasts mean providers need less power generating capacity and that can result in lower costs for consumers.

“Power demand growth that was expected to be reached in 2017 won‘t be achieved before 2030,’’ said Ghosh of Wood Mackenzie.

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