Part of the problem: in all seriousness, we don’t seem to know the extent of leakage throughout the natural gas system (from drilling to transportation to storage to end use …) and thus don’t have good data to leverage to support robust and accurate analysis of the trade-offs between the use of natural gas and other energy sources (whether for heating, electricity, or otherwise).
There are a series of studies and discussions on the issue. A reasonable one to start with is an EDF study. While the title sets the hackles of fossil fools, among enivronmental organizations, EDF rates as is quite business and natural gas friendly). The EDF website on a recent methane leakage study. To give an idea of the situation, they analyzed the carbon impacts of coal vs natural gas and the impact of natural gas leakage for this situation:
new natural gas combined cycle power plants reduce climate impacts compared to new coal plants; this case is true as long as leakage remains under 3.2%.
Alright, when comparing new (top of the line) vs new (top of the line), natural gas is better than coal as long as leakage is less than 3.2%.
Now, to be clear, the preceding sentence is
Assuming the Environmental Protection Agency’s (EPA) 2009 leakage rate of 2.4% (from well to city)
Last year, EPA discovered some differences in its 1990s-era emission estimates for a small number of key source types and those reported by natural gas companies to EPA in the voluntary Natural Gas STAR program. EPA used the best data it had available, mainly the self-reported estimates under the STAR program, which ended up roughly doubling its previous estimate of total industry emissions.
- The EPA doubled its leakage estimate based on the self-reporting in a voluntary program?
- That self-reporting comes from
- big players who are
- trying to show their best face and
- are theoretically committed to do better.
- This self-reporting doesn’t have the wildcatters, the small players, etc …
- And, again, this is the “self-reported estimates” which we can have some confidence weren’t targeting erring on making themselves look worse than reality (as opposed to better). And,
- That data is several-years time late and almost certainly doesn’t account well for fracking.
By the way, the EDF study lays out strongly why the embrace of the Pickens’ Plan was such lunacy:
At current leakage rate estimates, converting a fleet of heavy duty diesel vehicles to natural gas would result in nearly 300 years of climate damage before any benefits were achieved.
- Methane leakage is a serious problem.
- We do not really know how big a problem.
- Until we know how big a problem, be wary of claims about how natural gas is a climate change solution.
LEVELS of the potent greenhouse gas methane have been recorded at more than three times their normal background levels at coal seam gas fields in Australia, raising questions about the true climate change impact of the booming industry.