Post by muso on May 1st, 2012 at 8:48am
That analysis is flawed. It doesn't take into account methane emissions that would occur if the CSG were not to be extracted. :)
It's just a tad more complicated than that study reveals.
For a start, it all stems from the fact that the 100 year Global Warming Potential of methane is about 25 times that of carbon dioxide.
In areas where coal mining takes place, coal seam gas leaks to the atmosphere as a result of the extraction process. However if the CSG is extracted first, it reduces the pressure and reduces the emission rates to atmosphere.
On that basis, you could argue that the extraction and use of CSG actually reduces the carbon footprint associated with open cut mines, even if they are not currently in production. Any open gash in the countryside is continuously emitting methane, and some of these gashes are 100km long or longer (see the picture). The emissions associated with coal production are grossly underestimated because these are diffuse fugitive emission.
If we ceased CSG production from these areas, the methane emissions to atmosphere would increase. Any location where there is an intention to mine coal, shares the same long term benefit from CSG production.
I read about that study when it first came out, and it doesn't look at the whole picture. You would have to question the motivation behind it. (Who funded it?) It begs the question - where is the life-cycle analysis for coal mining? (dangerous thoughts - just as well that I'm anonymous)
There are various reasons for issuing a report like this. I deal with environmental consulting engineers all the time. You have to watch them like a hawk. Generally, reports like this are commissioned on behalf of industry for submission to the regulator. They tend to sneak in little recommendations that ensure that they will be kept in employment by way of future studies. You should see them whinge when you refuse to release payment of $500k studies until they tidy up the reports.
mine.jpg (49 KB | 62
)
It's just a tad more complicated than that study reveals.
For a start, it all stems from the fact that the 100 year Global Warming Potential of methane is about 25 times that of carbon dioxide.
In areas where coal mining takes place, coal seam gas leaks to the atmosphere as a result of the extraction process. However if the CSG is extracted first, it reduces the pressure and reduces the emission rates to atmosphere.
On that basis, you could argue that the extraction and use of CSG actually reduces the carbon footprint associated with open cut mines, even if they are not currently in production. Any open gash in the countryside is continuously emitting methane, and some of these gashes are 100km long or longer (see the picture). The emissions associated with coal production are grossly underestimated because these are diffuse fugitive emission.
If we ceased CSG production from these areas, the methane emissions to atmosphere would increase. Any location where there is an intention to mine coal, shares the same long term benefit from CSG production.
I read about that study when it first came out, and it doesn't look at the whole picture. You would have to question the motivation behind it. (Who funded it?) It begs the question - where is the life-cycle analysis for coal mining? (dangerous thoughts - just as well that I'm anonymous)
There are various reasons for issuing a report like this. I deal with environmental consulting engineers all the time. You have to watch them like a hawk. Generally, reports like this are commissioned on behalf of industry for submission to the regulator. They tend to sneak in little recommendations that ensure that they will be kept in employment by way of future studies. You should see them whinge when you refuse to release payment of $500k studies until they tidy up the reports.
mine.jpg (49 KB | 62
)