Nick
Electricnick.com

Transportation of coal and mining releases minimal CO2 compared to natural gas.
Depending on the mine, coal mining release significant fugitive CH4. Pipeline have fugitive emissions
natural gas and LNG processing have fugitive emissions as well, all of which are accounted for in the study.

“The working assumption is that all the upstream processes pre-combustion for LNG have dramatically fewer CO2 emissions than coal. ”

This study doesn’t use that as a working assumption, it details the individual contribution of each step of the process. If one has a critique of some indivivdual estimate, make a critique on technical grounds.

I agree your protest is completely ad hominem, framed by preconceptions, and without any stated technical merit.

Glad you like WordPress. I’m happy I made the switch, too.

Regarding your earlier comment about LNG. We’ve got to keep in mind what LNG in North America is for — marginal supply. That’s not from using natural gas to heat our homes, that’s for electricity generation mostly. The talk of building LNG facilities is to support another dash-to-gas by the power sector. So when comparing, yes, I’m comparing coal and LNG for power generation. I agree you can’t ship coal to everyone’s home, and natural gas is terrific for home heating, but we’ve got enough domestic natural gas for this without the need for LNG.

And sorry, I didn’t say “coal produces less CO2 than natural gas.” Please READ my post. I said when LNG is factored in the gap between coal and natural gas narrows.

Natural gas on the other hand is regularly transported ’round the world, yet still manages to maintain a sizable net energy surplus, despite transportation losses.

So let’s try and compare apples-to-apples. Natural Gas is moved great distances because it is easy to move. Coal simply can’t fill that same roll. So you can’t simply say “coal produces less CO2 than natural gas” (which isn’t true in any case), because coal is used in a far more restrictive fashion. If Natural Gas was used for nothing but electricity production, then the electricity plants could be right beside the gas fields (like how coal plants are right beside mines), meaning far less CO2 production (and methane leak) due to transportation would take place. But that isn’t the case, is it? Most Natural Gas is used for things like heating, and therefore needs to be sent straight to the consumer. I dare you to try that with coal. It’s been done in the past, and it doesn’t work well at all.

Therefore this is not an apples-to-apples comparison. It’s similar saying, “solar works great in the Sahara Desert, so clearly it will work great in Inuvik as well!!” It’s simply not a valid comparison to make.

For the record, I didn’t say LNG and coal were equal on emissions, I said the gap is narrower than the LNG group study makes it out to be. Even more narrow depending on where the LNG is coming from. If it’s coming to the U.S. east coast from Trinidad, then it’s not so bad. If it’s coming from Russia or China, then you have to factor in added transportation-related emissions. Coal is sent much shorter distances by train. Also, don’t underestimate the amount of energy it takes to compress and decompress the gas, as well as the methane that escapes during this process. The key thing here is methane — fugitive methane emissions in every step of the LNG process are 21-times CO2′s potency. Coal mining and transportation doesn’t release much methane.

Isn’t that veering a little bit into ad hominem territory? The only “cause for suspicion” anyone should need is the natural empirical skepticism with which any data set should be treated until verified, and the only reason to accept or reject data should be the results of that verification (which really, to be fair, should be checked against more than just one other study, no matter one’s opinion of the comparative bias or lack thereof).

“Sure, if we’re just talking combustion, then coal emissions are definitely 2 to 2.5 times greater. But when you factor in upstream emissions related to exploration, extraction, transportation, LNG conversion, etc. then the mining and transportation of coal has a much lower carbon footprint.”

I have to admit I could use some more explanation on that. Why is the LNG upstream emissions footprint so much greater than coal’s? And is it really so much greater that LNG’s reduced combustion/use emissions when compared to coal’s can’t compensate, especially when economy of scale kicks in? You’d think that by weight and volume alone coal would be more energy- (and emission-)intensive to get out of the ground.

I don’t necessarily disagree with the claim that LNG offers no real overall emission reduction benefit, but comparative statistical analysis of such complex fields as this tends to leave enough room for overlooked data as to make different conclusions both possible and honest.

Transportation of coal and mining releases minimal CO2 compared to natural gas. But add LNG into the mix and you’ve got more potential for fugitive emissions as well as the energy used to ship this stuff from other continents and the energy required to compress and decompress the gas. It strikes me as a leap of logic to suggest that would be less carbon-intensive that mining and transporting coal. I’m not saying the numbers in the study aren’t there. I’m saying they’re wrong, and the more independent Carnegie Mellon study confirms that.