Hydraulic Fracture Drilling-Part 11

Opinion: Dirty Little Secret About Natural-Gas Fracking: Fugitive Methane Emissions

 

 

July 10, 2015


According to recent research, the global-warming impact of FMEs is two-thirds greater than coal’s over the near term






Credit: Amanda Brown
R. William Potter

In energy circles, conventional wisdom holds that natural gas is the ideal clean and cheap “transition fuel.” TV ads tell us that gas is the bridge from the fading era of fossil fuels to a newly emerging sustainable future based on renewable energy (solar and wind).

Don't believe it.

As so often is the case, what passes as conventional wisdom turns out on closer inspection to be flat-out wrong or at best half true. In fact, available data and numerous studies now show that natural gas -- depending on its source -- can be as bad if not much worse for planetary health than coal, the usual nemesis.

When natural gas's impacts on the environment are measured only at the point of consumption, gas is both cheaper and cleaner than burning coal to produce electricity. As gas-industry advertisers intone, “natural gas has half the CO2 footprint of coal” or “clean-burning gas has half the carbon footprint of coal.”

True enough at the burner tip. But when gas is measured across the entire fuel cycle -- from drilling, extraction, and transmission through rapidly-built pipelines to the burner tip, a very different, and potentially ominous picture emerges.

The problems start with the production segment of the fuel cycle. Increasingly, new sources of gas come from fracking. This process drives chemicals and water through wells at very high pressure to split open (fracture) sedimentary rock, trapping gas fields that can be forced to the surface.

Fracking is rapidly becoming the new source of gas for New Jersey utilities, arriving here from hundreds of wells across Pennsylvania’s Marcellus shale formations, where a frenzy of drilling is leading to hurried efforts to lay pipelines across both states, generating a great deal of opposition along the way.

Fracking can pollute local groundwater, residential wells, and waterways -- besides triggering earthquakes, as in Oklahoma – while also fouling the air. Much worse, however, the process releases fugitive methane emissions (FMEs), a major contributor to global warming and climate change that is threatening to everyone.

How bad is FME? Worse than burning coal in the near term. That’s because methane gas remains suspended in the atmosphere for “only” 10-20 years, compared with carbon dioxide), the major greenhouse gas by volume from coal, which stays airborne for a century or more.

When measured over a two-decade period, methane pollutants do far more climate damage than carbon. The estimates of FME impacts over that 10-20 year period vary from a low of 70 percent of coal (according to the natural-gas industry) to a high of 400 percent greater than the carbon footprint of coal, according to independent researchers at the NASA Goddard Space Institute. If we average the published estimates, natural gas has a global-warming footprint that’s 167 percent of coal’s -- or two thirds greater impact over the near term.

(There is a short informative video on methane and its role in global warming available online, featuring Dr. Drew Shindell, a leading climate scientist formerly with Goddard and now at Duke.)