THE CASE FOR HYDROFRACKING - Hydrofracking: What Everyone Needs to Know - page 47

some argue that methane leaks in gas operations nullify those benefits, because
methane (the primary component of natural gas) is a formidable greenhouse gas.
First the good news. Between 2007 and 2012 the United States reduced its
greenhouse gas emissions by 450 million tons, the biggest drop of any nation in
the world. 53 Hydrofracking advocates are quick to claim that this is a result of the
nation's fundamental shift from coal to natural gas and renewable energy.
In 2000, coal powered 52 percent of US electric generation, natural gas
provided 16 percent, and renewables were only 9 percent. By 2012, according to
the Energy Information Administration, coal had plummeted to 38 percent, gas had
jumped to 30 percent, and renewables had risen to 12 percent. 54 “Pragmatic leaders
understand … that with natural gas we don't have to choose between our economic
and environmental priorities. Instead, responsible natural gas development is hav-
ing very real and positive impacts in the 32 states that are home to this abundant
domestic energy source,” the American Natural Gas Alliance writes in a recent re-
port. 55
A study by the environmental investor group CERES found a nearly 70 percent
reduction in sulfur dioxide and smog-forming nitrogen oxide over the past 20
years, thanks to growing use of natural gas among the nation's top 100 utilities. 56
Nearly half the reduction came in just a two-year period from 2008 to 2010. The
EIA has similarly noted that US carbon emissions from the power sector are at
20-year lows, largely due to the increasingly prominent role of natural gas in the
nation's energy portfolio. 57 (The European Union, by contrast, has seen its green-
house gas emissions rise over the same timeframe, despite a more concerted effort
to tackle global warming than the United States has made. 58 This is driven by the
EU's increased reliance on coal for generating power.)
However, methane is the main component of natural gas, and it has a notori-
ously potent greenhouse effect, with a global warming potential 72 times higher
than carbon dioxide—the leading greenhouse gas—over a 20-year period, accord-
ing to the Intergovernmental Panel on Climate Change, and 20 times greater over
a 100-year period, according to the EPA. 59 The EPA has long held that natural gas
operations represent the leading source of methane leaks in the United States, ac-
counting for 145 metric tons in 2011. (The second-largest source of methane was
“enteric fermentation,” aka gas emitted by cows and other animals, at 137 metric
tons. The third-largest source were landfills, which emitted 103 metric tons.) 60 Yet
the EPA estimates that all sources of methane combined represent just 9 percent of
greenhouse gases.