Friday, October 23, 2009

Sequestration and Education

Yesterday afternoon I began scrutinizing the Senate climate bill, S.1733, widely referred to as the Kerry-Boxer bill. Like the Waxman-Markey bill that the House passed in June, the scope of Kerry-Boxer goes far beyond the establishment of an economy-wide cap & trade system for reducing greenhouse gas emissions, though at a comparatively skimpy 821 pages it has yet to acquire as much baggage as its counterpart accreted on its way to a floor vote. I was struck by the emphasis both bills place on carbon capture and sequestration (CCS), not just as a technology that receives significant support, but as the only viable pathway offered for new coal-fired power generation. However, as I looked through the provisions relating to permitting of sequestration sites and the innocuous-sounding section 812, "Performance Standards for New Coal-Fired Power Plants", I spotted a significant omission. There's nothing here to address what might constitute the largest non-technical barrier to implementing CCS. Public acceptance of it entails a significant educational effort on the efficacy and safety of this new technology. That will require going beyond the details of CCS to provide Americans a primer on basic geology.

The stakes are high. Despite recently losing some market share to natural gas and renewables, coal-fired power plants make up the single largest source of electricity in the US by a wide margin. In the 12 months through July, coal accounted for 46% of US power generation, compared with just 3% for non-hydro renewable energy. Short of simply shutting down every coal-fired power plant and leaving a gaping hole in our national electricity supply that the current generation of renewables can't yet fill, we need to find a way to control the emissions from coal directly. That's where CCS comes in. The coal power performance standards in Waxman-Markey and Kerry-Boxer would require that by no later than 2027 any new coal-fired power plants licensed after 1/1/09 must cut their net CO2 emissions by at least half. CCS looks like the only practical way of doing that--if you can call something that has been deployed so sparingly practical. But how can CCS be implemented if the public isn't willing to have CO2 stored underground anywhere?

CCS is new, but it's not so new that it hasn't already attracted pushback. Earlier this year Shell encountered significant opposition to injecting CO2 into a depleted gas field in the Netherlands. Meanwhile Vatenfall's project at Schwarze Pumpe in Germany is apparently venting its captured CO2 to the atmosphere, because the firm can't get a permit to inject it. "Not in My Ground", is how another article described opposition to carbon sequestration at an Ohio ethanol plant. My Google search even turned up a blog entitled, "Citizens Against CO2 Sequestration." Aside from the technical challenges associated with separating, transporting and injecting CO2 into geological storage sites, do these opponents have a scientific basis for being concerned about the health and safety risks? Perhaps, though an article on the subject cited by the Citizens Against blog that refers to the health hazards of drinking water mixed with CO2 had me rolling my eyes. Perhaps the author was unaware that hundreds of millions of us do that every day; we call it soda pop, and it's a big business.

Rather than dismissing all this as a simple case of uninformed NIMBYism (or as the Guardian newspaper in the UK referred to it, "numbyism", as in not under my back yard) I suspect it reflects a fundamental gap in the public's understanding of what lies beneath its feet. I simply cannot count the number of people I've encountered in the course of my long career in energy who were under the impression that oil was found as pools in giant underground caverns, rather than contained within tiny pores in solid rock strata. If most people so badly misunderstand the geological basis of a technology as established and commonplace as oil & gas drilling, how on earth can we expect them to have a coherent picture of what happens to CO2 when we pump it underground? Of course they're going to fear it could all come right back out and possibly asphyxiate them, in the manner of the volcanic CO2 seepage at Lake Nyos in Cameroon and elsewhere.

From my own perspective, the existence of enormous natural gas reservoirs--confusing terminology, perhaps--constitutes a sufficient proof of concept by demonstrating that gases can be stored safely underground for intervals as long as millions of years. If impermeable cap rock can seal in billions or trillions of cubic feet of methane, the molecular diameter of which is smaller than that of CO2, then once the CO2 is down there, the vast majority of it is going to stay there. But just as telling people that a flu vaccine is safe apparently leaves large numbers of them unconvinced, I conclude we need to invest a fair amount of time, attention and resources into educating the public about the science and safety of injecting CO2 under the ground, before we can base our national energy strategy on this technique.

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