Ignore Keystone XL, focus on clean coal?

An update to the previous entry on challenges to scientists doing advocacy:

Nocera’s latest editorial (A Real Carbon Solution) is about a coal gasification project in Texas that he bills as a fossil-fuel-industry-friendly contribution to combating climate change (as opposed to Hansen’s advocacy).  I have to comment on a couple of misleading statements that are tangentially related to my own research:

“because the gasification process doesn’t burn the coal, it makes for far cleaner energy than a traditional coal-fired plant”

This is an absurdly misleading definition of gasification; the process involves partially oxidizing (“burning”) the fuel into intermediates (largely CO in this case) that can then in turn be burned via more advanced energy conversion pathways.  There are many advantages to this process; 1) the gaseous intermediary fuel can be used in high-efficiency combined-cycle plants, 2) it facilitates the control of emissions of mercury and particulates (though the process generates other new pollutants as well), and 3) the technology can be configured to produce a very pure stream of CO2, which lowers the cost of geological sequestration because no costly gas separation technology is necessaryBut to imply that the fuel is not ‘burned’, i.e. eventually mostly oxidized to CO2, is highly misleading.  IF YOU DON’T EVENTUALLY OXIDIZE THE FUEL, YOU DON’T GET ANY ENERGY FROM IT!

“it will capture some 90 percent of the facility’s already reduced carbon emissions… a process called enhanced oil recovery… this technology could be a climate-saver”

From a lifecycle emissions accounting standpoint, I’m not sure you would count CCS as reducing CO2 emissions if it’s only economically viable when used to extract petroleum that would otherwise be unrecoverable (i.e. when the carbon storage is fundamentally linked to new carbon emissions that wouldn’t necessarily occur otherwise).  At the very least, I would think the estimated sequestration would have to be adjusted to reflect a large indirect emissions effect associated with increased oil extraction.  I haven’t really seen any literature on this yet, though my guess is that we will start to see some papers challenging the basic accounting stance like we did for cultivated biofuel feedstocks in 2008 and forestry feedstocks more recently.

“Gas-fired power plants, which already emit 50 percent less carbon than coal-fired plants, could become even cleaner if they included the carbon-capture technology”

The article consistently conflates three different pieces of technology: 1) coal gasification, 2) oxy-fuel combustion/gasification, and 3) CO2 sequestration/storage.  While the Odessa plant might include elements of all three (I don’t know the details), it’s not clear that it’s fundamentally advancing the technology on anything but #1.  Yet adding carbon capture to natural gas plants only requires pieces #2 and #3, so it’s not clear how much if at all the Texas technologies will be transferable to the natural gas sector.

There is a very valid debate on about whether ‘clean coal’ and other technologies that couple fossil fuel use and CCS have a role in the future energy economy, and, more broadly, whether it’s better to put the brakes on CO2 emissions now or to wait until you’ve throw a lot of money at R&D that will make that decarbonization less painful (the fundamental issue that Nocera’s articles are getting at, I think).  But beware that this new editorial produces a very crude strawman of that debate, and fundamentally mis-characterizes some interesting but still immature advanced energy technologies in service of his argument.

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