Increasing prices for natural gas are prompting more dependence on coal-fired power plants — and a corresponding hike in carbon dioxide emissions, a report by a national environmental nonprofit has found.
Emissions of carbon dioxide from coal-fired power plants had declined 13 percent since 2005, according to the Environmental Integrity Project.
But in the first quarter of 2013, there was a "substantial" jump in emissions, the group said. Compared to the first quarter of 2012, carbon dioxide emissions rose 7.1 percent.
With atmospheric carbon dioxide levels at one key monitoring station recently topping 400 parts per million — while not considered a tipping point, nevertheless a milestone — the heat-trapping gas is back on the hot seat.
How and where and how much we cut emissions are all ... up in the air.
The Environmental Integrity Project cited projections from the U.S. Energy Information Administration showing that coal-based generation will increase 8.7 percent this year, compared to last.
"As natural gas gets more expensive, coal is finding its way back into the U.S. electricity generation picture, and that means higher carbon dioxide emissions," said Eric Schaeffer, EIP director.
Power companies plan to retire 45 gigawatts of coal capacity through 2016 due to low natural gas prices, Schaeffer said.
In this region, NRG Energy officials recently announced the closure of a Berks County plant, and the closure or refueling of the Portlant plant north of Easton.
All that might suggest lower emissions.
But a change in other factors — not only natural gas prices, but also the increased availability of renewables, moderate demand and the cost of complying with long-delayed Clean Air Act rules — "can encourage plant operators to squeeze more generation out of remaining coal plants," Schaeffer said.
Pennsylvania ranked third in the nation in overall carbon dioxide emissions from its power plants in 2012, the EIP report found.
However, looking at efficiency — emissions per megawatt hour — Pennsylvania ranked 31st.
State emissions had dropped 8.85 percent between 2005 and 2012, but in the first quarter of this year, they rose 10.88 percent, compared to the first quarter of 2012.
Among individual plants, Bruce Mansfield in the western part of the state was the nation's sixth-highest emitter of carbon dioxide in 2012.