The Algae Biomass Organization (ABO), an algae industry trade association, quickly issued an enthusiastic statement hailing the option as “a huge win for the algae industry, and one we have been working towards for more than a year. The rule gives new certainty to a number of companies across the nation that are commercializing algae-based technologies that convert carbon dioxide generated at power plants into fuels, feeds, fertilizers and other valuable products.”

Algae biofuel company Algenol, whose pathway for algae-derived ethanol received EPA approval earlier this year as as advanced biofuel (50% greenhouse gas reduction) (earlier post), issued its own statement heralding the CPP for acknowledging “for the first time the value of carbon utilization, the cornerstone of Algenol’s Direct-to-Ethanol technology, as a method for utilities to reduce emissions from electricity production and comply with the Clean Air Act requirements for CO₂ emissions.”

The actual text of the CPP rule is, however, more reserved. In a section discussing the potential for the application of CCU (VIII.I.2), EPA noted that potential alternatives to storing CO₂ in geologic formations—i.e., carbon capture and storage, CCS—are emerging and may offer the opportunity to offset the cost of CO₂ capture.

Examples the agency first adduced in the section included the storage of captured anthropogenic CO₂ may be stored in solid carbonate materials such as precipitated calcium carbonate (PCC) or magnesium or calcium carbonate, bauxite residue carbonation, and certain types of cement through mineralization.

EPA cited the Skyonics Skymine project as an example of captured CO₂ being used in the production of carbonate products—in this case, sodium carbonate and sodium bicarbonate.

However, consideration of how these emerging alternatives could be used to meet CO₂ emission performance rates or state CO₂ emission goals would require a better understanding of the ultimate fate of the captured CO₂ and the degree to which the method permanently isolates the captured CO₂ or displaces other CO₂ emissions from the atmosphere.

Several commenters also suggested that algae-based CCU (i.e., the use of algae to convert captured CO₂ to useful products – especially biofuels) should be recognized for its potential to reduce emissions from existing fossil-fueled EGUs.

Unlike geologic sequestration, there are currently no uniform monitoring and reporting mechanisms to demonstrate that these alternative end uses of captured CO₂ result in overall reductions of CO₂ emissions to the atmosphere. As these alternative technologies are developed, the EPA is committed to working collaboratively with stakeholders to evaluate the efficacy of alternative utilization technologies, to address any regulatory hurdles, and to develop appropriate monitoring and reporting protocols to demonstrate CO₂ reductions.

In the meantime, state plans may allow affected EGUs to use qualifying CCU technologies to reduce CO₂ emissions that are subject to an emission standard, or those that are counted when demonstrating achievement of the CO₂ emission performance rates or a state rate-based or mass-based CO₂ emission. State plans must include analysis supporting how the proposed qualifying CCU technology results in CO₂ emission mitigation from affected EGUs and provide monitoring, reporting, and verification requirements to demonstrate the reductions. The EPA would then review the appropriateness and basis for the analysis and the verification requirements in the course of its review of the state plan.

—EPA CPP