Green Patent Blog

I depart from intellectual property issues today to report on a significant environmental law decision out of Georgia that could have major implications for the carbon capture and sequestration market. 

On June 30th, the Fulton County Superior Court overturned a decision of the Georgia Environmental Protection Division (EPD) issuing a permit to Longleaf Energy Associates, LLC (Longleaf), a shell company owned by LS Power, to build a 1200 megawatt coal-fired power plant in Early County, Georgia.  (see the Rethink Georgia press release here and the greentech media story here)

The key to Judge Thelma Wyatt Cummings Moore’s decision (longleaf-decision.pdf) was the Supreme Court’s ruling last year in Massachusetts v. EPA that carbon dioxide is an “air pollutant” subject to regulation under the federal Clean Air Act (Act).

Under the Act and the EPA’s regulations, certain areas of the country designated “attainment areas” must keep pollution levels within prescribed air quality limits (Early County is once such attainment area).  This includes the requirement that any new “major emitting facility” (a term that includes fossil fuel-fired electric plants such as the Longleaf facility) obtain a permit and abide by the emissions limitations outlined in the permit.

Major emitting facilities like the Longleaf facility must incorporate the “best available control technology” (BACT) to limit pollution.  This BACT analysis entails a determination by the permitting authority of the maximum reduction of each regulated pollutant for the particular project.  The emissions limitations in the facility’s permit must be set based on that “best available control technology.”

The Sierra Club and the Friends of the Chattahoochee (Petitioners) challenged the Georgia EPD’s decision to issue a permit for construction of the Longleaf plant.  After an EPD administrative law judge (ALJ) dismissed the challenge and upheld the permit, the Petitioners appealed to the Fulton County Superior Court alleging that the ALJ erred by making no findings on, among other things, carbon dioxide emissions, including failing to require that the EPD do a BACT analysis.

The court agreed with Petitioners and found the ALJ’s decision erroneous for deferring to the EPD’s inadequate permitting process.  In particular, the court found that, because carbon dioxide is an air pollutant under the Act, a BACT analysis should have been conducted by the EPD to set a carbon dioxide emissions target for the Longleaf project.

The immediate result is that the Georgia EPD will have to conduct a carbon dioxide emissions analysis, and Longleaf and its developers, LS Power and Dynegy Inc., will have to comply with the resulting emissions target to build the power plant. 

If other states follow the Georgia ruling, future coal-fired power plants will have to be designed to reduce carbon dioxide emissions if they are to gain regulatory approval.  One way to do that is to equip new plants with carbon capture and sequestration technology.  Thus, the decision could increase the demand for the technology and be a welcome boost to the carbon capture industry.

This discussion was supposed to be part of Green Patent Blog’s Best of 2007 post, a project that got lost amid holiday festivities.  So here it is now: 

While the important effort to reduce or eliminate greenhouse gas emissions continues, removing previously emitted greenhouse gases from the air may become necessary depending on how dire the climate change problem really is.  That’s what Columbia University physicist Klaus Lackner’s technology does.  Dr. Lackner is a named co-inventor on at least three patent applications and one issued patent relating to capturing and recovering carbon dioxide from the air. 

U.S. Application No. 2006/0051274 is directed to an apparatus for capturing CO2 called a laminar scrubber.  The laminar scrubber is a wind collector having a set of flat plates, or lamellae, arranged centimeters apart from each other.  Air is sucked through the plates by a natural pressure gradient, wind or convection.  A hydroxide based sorbent flows down the plates while a layered airflow passes through the thin spaces between the plates.  The contact between the air and the sorbent causes a chemical reaction which removes the carbon dioxide.  The patent application contemplates groups of laminar scrubber units combined in larger superstructures - what some of the press reports have called synthetic trees. (read articles here and here)

U.S. Application Pub. No. 2007/0187247 covers the next steps of the process, namely recovering the CO2-filled sorbent and separating the CO2 from the sorbent liquid.  The electrochemical methods of the application are more direct and energy efficient than prior art processes, which require transferring carbonate ions to calcium carbonate and then burning off the calcium.  Lackner’s process uses electrodialysis, in which the sorbent flows through cells having compartments separated by membranes.  At one end of the cell is a positively charged anode, at the other a negatively charged cathode.  The membranes also are charged to allow the passage of only positive ions or negative ions between compartments; a positively charged membrane traps positive ions while a negatively charged membrane traps negative ions.  Positive ions flow toward the cathode, negative ions flow toward the anode, and the ions are trapped in compartments along the way based on the type of membrane separating each compartment.  This structure separates the sorbent solution into hydroxide and CO2 by trapping and concentrating the negatively charged hydroxide ions in a compartment bounded by a negatively charged membrane.  The CO2 is released in a concentrated, pressurized stream, which can be sequestered or used for other purposes.