Exporting our carbon emissions

Ohio Power Plant

[audio:http://wamcradio.org/EarthWise/wp-content/uploads/2012/10/EW-10-08-12-CO2-US.mp3|titles=EW 10-08-12 CO2 (US)]

On the face of things, it sounds like excellent news. The Department of Energy recently reported that in 2011, the amount of carbon dioxide our nation emitted from energy production declined. This was the third time in four years that such a trend was noted.

But the drop in emissions wasn’t because Americans decided to take up carpooling or turn down their air conditioners. It was due to the mild winter of 2011 and an increase in the use of natural gas, which is now abundant and cheap through the exploitation of shale gas.

Power plants generate 40 percent of U.S. carbon emissions. And the Department of Energy noted that in 2011, “power generation from natural gas, the least carbon intensive of the fossil fuels, increased by 3%, while generation from coal declined by 6%.”

According to Harvard’s Michael McElroy, “Generating 1 kilowatt-hour of electricity from coal releases twice as much CO₂ to the atmosphere as generating the same amount from natural gas. So a slight shift in the relative prices of coal and natural gas can result in a sharp drop in carbon emissions.”

Decade-low natural gas prices helped curb our carbon emissions. But reductions in coal-fired electricity didn’t translate necessarily into reductions in CO2 emissions. Over the past few years U.S. coal production has remained steady, and we have grown our exports to Asia. Or, to put it another way, we are exporting our carbon emissions.

The silver lining in the Department of Energy’s report is that power generation from renewable sources continues to rise. Global adoption of clean energy is what is really needed if we are to stem climate change.