Power industry’s carbon dioxide emissions decrease

The power industry significantly cut its carbon dioxide emissions last year as it continued to shift from coal to cleaner-burning natural gas and emissions-free renewable energy sources to generate electricity.

The drop was so dramatic — nearly 5 percent — that it offset emission increases from other business sectors and helped the U.S. slightly cut its overall carbon dioxide emissions in 2017, according to the Energy Department.

The power industry is one of the biggest producers of carbon dioxide, a greenhouse gas that traps heat in the atmosphere and contributes to rising global temperatures that are changing the Earth’s climate.

But in recent years, as natural gas production has boomed and prices have plunged, power companies have increasingly shuttered coal-fired plants in favor of natural gas-fired plants.

The costs of wind and solar energy have fallen significantly, too, in recent years, making them competitive with coal and other fossil fuels and allowing them to take larger shares of the nation’s electricity generation.

Less demand for electricity is also playing a role in reducing carbon dioxide emissions, the Energy Department reported. Electricity sales last year were the lowest since 2009, when the U.S. economy hit bottom during the last recession. The government attributed last year’s lower sales to milder weather.

Overall, energy-related carbon dioxide emissions decreased last year to 5.14 billion metric tons, about 1 percent lower than in 2016.

Energy-related emissions of carbon dioxide have fallen in seven of the past 10 years, the Energy Department reported, and are 14 percent lower than what they were in 2005.