Today, the American Clean Skies Foundation released a life cycle study finding greenhouse gas emissions from natural gas-fired electricity is 50% less than coal. See www.cleanskies.org/ghgemissions. This study was authored by Greg Staple and Dr. Joel Swisher, who among other things is a Senior Fellow at the Rocky Mountain Institute and a consulting professor of engineering at Stanford University.
The Staple-Swisher paper will be the first of several as more life-cycle studies from highly credible institutions are nearing completion.
Staple and Swisher use the most recent 2011 EPA data on methane leakage rates (not used by Horwath), accepted IPCC global warming potential protocols (not used by Horwath), and calculate emissions for both the production of coal and gas plus the combustion of coal and gas. Unlike Horwath, the Staple-Swisher paper used empirical data readily available concerning the efficiency with which coal plants burn coal and the efficiency with which gas plants burn gas to produce an actual kilowatt-hour of electricity that we then use at our homes and businesses.
Coal plants are less efficient than gas plants. Coal plants require more fuel than gas plants do to produce a kilowatt-hour. The lower efficiency of coal plants are a major reason why they emit more carbon per kilowatt-hour of electricity actually generated than gas plants do.
And if you don't want to read the paper, though I recommend it, here are its principal conclusions:
1. Existing gas fired plants emit 51% less greenhouse gas pollution per kilowatt-hour than existing coal plants;
2. A new gas-fired combined cycle unit produces about 52% less GHG pollution per kilowatt-hour than a new coal fired plant;
3. A new gas-fired combined cycle unit produces about 58% less GHG pollution than the average coal plant and 63% less than a typical older coal plant.
Will this news be fit to print in the NYT? Again, this will be the first of several studies arriving at materially different conclusions to Professor Horwath and debunking his paper.