Is natural gas really a clean fuel?
“Natural gas is marketed as a clean fuel with less impact on global warming than oil or coal, a transitional fuel to replace other fossil fuels until some distant future with renewable energy. Some argue that we have an obligation to develop Marcellus Shale gas, despite environmental concerns. I strongly disagree.
“Natural gas as a clean fuel is a myth.”
- Cornell professor: “Gas and drilling not clean choices”
See also Cornell scientist tarnishes natural gas’s clean image
Modified from a post on MarcellusGasInfo:
The following is an outline from James Lovelock’s book, Revenge of Gaia, pages 74-76. Lovelock is a member of Britain’s Royal Society (a scientific body) and originator of the Gaia theory, which postulates that the atmosphere, oceans, and biosphere (all life) compose a single system that regulates the Earth’s climate.
——————
To reduce global warming, governments welcome the chance to burn natural gas instead of coal or oil.The main constituent of natural gas is methane – one molecule is composed of 1 carbon and 4 hydrogen atoms.
For the same amount of energy, methane combustion releases only 1/2 as much carbon dioxide as burning oil or coal.
Unfortunately, some natural gas leaks into the air before it is burned. Society of Chemical Industry’s 2004 report indicates 2%-4% of natural gas is lost to leakage. Most of the leakage is at production sites, but leakage also occurs in pipelines and in our homes.
Methane is 24 times more potent a greenhouse gas than carbon dioxide.
Methane has a shorter residence time in the air: 8% oxidizes each year.
In 12 years, only 37% of escaped methane remains, the rest having oxidized into carbon dioxide and water vapor.
Carbon dioxide has an effective residence time in the air of between 50 and 100 years.
If only 2% (the conservative end of the 2-4% estimate) of natural gas leaks before burning, it causes, over a period of 20 years, a peak global warming equal to coal burning.
If 4% leaks, natural gas causes 3X more warming than coal burning over a 20 year period.
The claim that natural gas halves carbon dioxide emissions is only true if there are no leaks anywhere (and also if the CO2 emissions from the very hydrocarbon-consumptive extraction process is not factored in).
Difficult to find estimates of natural gas leakage. An April, 2004 article in the journal Nature estimates 1.4% leakage from Russian piplines and 1.5% from US pipelines. This report does not include leakage at production sites or when the gas is burned.
Failure to consider the effects of natural gas leakage on global warming is a serious gap in our knowledge. The International Panel on Climate Change(IPPC) should study this phenomenon further.
0