Feasibility and Carbon Capture and Sequestration: Will Commercial Deployment of Carbon Capture and Sequestration Pass the Test?

• Publication year: 2009

Margaret S. Davis⁰

The United States' government has developed a policy that supports the use and deployment of commercial level carbon capture and sequestration as a method for reducing carbon emissions from major electricity generating sources. The Environmental Protection Agency must determine which current provisions of the Clean Air Act are best used to regulate greenhouse gases and then apply the feasibility principle to determine what level of emissions reductions will be required. The Clean Air Act will be, at best, a clumsy tool for regulating greenhouse gases, and the feasibility determinations that the Environmental Protection Agency will have to make in setting the technology-based standards under the Act are inexact and time consuming. In order for America to act efficiently and effectively to address climate change causing greenhouse gas emissions and to put in place innovative technology, such as carbon capture and sequestration, new legislation should be enacted which establishes a new statutory regime for the regulation of these chemicals and a new, less discretionary process for putting innovative and highly effective emissions reducing technologies in place.

I. Introduction

Increasingly, implementation of methods for managing the greenhouse gas ("GHGs")¹ emissions that cause climate change² is a hot topic of discussion for America and the world.³ Considering the technological complexities and cost of reducing GHG emissions and America's broader policy objectives of reducing the effects of climate change, attaining a balance between existing regulation and new policies⁴ is a critical step in properly implementing effective emissions reductions.

The feasibility principle guides the balancing of factors when determining what level of emissions reductions may be possible.⁵ Under the current statutory regime, the Clean Air Act's Prevention of Significant Deterioration program would likely apply.⁶ Language such as "best" and "achievable" are what would guide the Environmental Protection Agency's standard-setting decisions.⁷ These terms are broad and could lead to any number of standards being set. The feasibility principle guides the application of this standard by providing both a ceiling and a floor for what the standard may demand.⁸

The aim of this Recent Development is to consider the technology and policy that must be in place prior to the Environmental Protection Agency ("EPA") or another federal agency finding that commercial deployment of carbon capture and sequestration ("CCS") is a feasible means of reducing carbon dioxide ("CO₂") emissions. Part II provides a background of recent actions by the Supreme Court and United States Congress on CO2 emissions. Part III discusses the technology as it stands today, specifically, the scientific and economic barriers to large-scale implementation of CSS. Part IV examines EPA's historical and current implementation of "feasibility." Finally, Part v addresses how current statutory language might apply to commercial deployment of CCS⁹ in the United States and the policy considerations that follow. As federal agencies determine the feasibility of commercial deployment of emissions reducing technologies under the Clean Air Act ("CAA"), new federal legislation, such as the American Clean Energy and Security Act, may be required to ensure proper implementation of innovative technologies.

II. Background

In the groundbreaking case Massachusetts vs. EPA,¹⁰ the United States Supreme Court substantively weighed in on the issue of climate change for the first time. The petitioners in this case were a collection of states and non-profit organizations who requested that the EPA regulate new automobile emissions standards under § 202 of the CAA.¹¹ The majority opinion declared that, to date, the scientific evidence indicates that climate change is a real and current phenomenon.¹² As a result of this decision, the EPA released a proposed endangerment finding for GHGs.¹³ This proposed finding would list GHGs as air pollutants under the definition of air pollutant in § 302 of the CAA.¹⁴ Once this agency finding is final,¹⁵ the EPA may be obligated to promulgate regulations for GHG emissions on stationary sources of carbon dioxide and greenhouse gases, such as electricity generating units and industrial factories.¹⁶

The U.S. Congress has taken up the issue of climate change.¹⁷ In June 2009, the U.S. House of Representatives passed the American Clean Energy and Security Act ("ACES"), H.R.2454, which has vast implications for GHG emissions in the United States through provisions including national energy efficiency standards,¹⁸ a GHG cap-and-trade program,¹⁹ and funding for communities that will be directly impacted by the effects of climate change.²⁰ A draft of the Senate's companion bill was introduced by Senators Boxer and Kerry in September 2009,²¹ with floor debate on the issue possible in fall 2009, though it is more likely to occur in spring 2010.²² This proposed legislation would lead to economic constraints on sources of GHG emissions²³ that are defined as regulated entities in the bills,²⁴ creating a system in which there will be a unit price per ton on GHGs released into the atmosphere.²⁵

As carbon regulation looms,²⁶ either through regulatory mechanisms under current statutory structure or through new legislation,²⁷ the coal utility industry, which is one of the largest sources of CO₂ emissions in the United States,²⁸ is developing technologies to keep this fuel source a viable option.²⁹ Power companies are exploring options such as changing to more efficient fuel sources for old electricity generating units. For example, natural gas may be used to produce electricity while emitting less CO₂ per unit of energy produced.³⁰ Industry is also exploring new technologies, which burn fuel more efficiently and thus more cleanly.³¹

One of the primary ways the coal utility industry hopes to reduce emissions is through the capture and storage of emissions.³² CCS is a process by which the emissions from a source,³³ primarily CO₂, are captured and stored indefinitely in geologic formations.³⁴ CCS could potentially reduce a given source's CO₂ emissions by eighty percent to ninety-five percent³⁵ and could contribute to projected international CO₂ emissions reductions by nineteen percent.³⁶ The risks, of course, are great.³⁷ For instance, accidental leakage of stored CO2 could create localized risks to the environment and public health³⁸ and reverse any climate benefit gained from capture and sequestration.³⁹

Despite the fact that commercial capacity⁴⁰ for CCS is, at best, years away,⁴¹ Congress and industry are moving forward with research and development of this technology.⁴² For example, Congress included one billion dollars of funding to promote CCS research in the stimulus bill in 2009.⁴³ Most recently, ACES, passed by the House of Representatives in June 2009, includes extensive provisions for research and incentives to industry to implement the technology early.⁴⁴

III. CCS Technology

There are many ways in which carbon may be sequestered,⁴⁵ but this Recent Development will focus on geologic CCS. CCS technology allows for the capture of the emissions from a "stationary source,"⁴⁶ the purification and concentration of the CO₂ in those emissions, and the transportation and storage of "supercritical CO₂"⁴⁷ in an appropriate geologic formation for hundreds to thousands of years.⁴⁸ If this sounds too simple to be true, it is. Each step takes technical precision and occurs at non-negligible cost.⁴⁹

A. Capture, Purification, and Concentration

When CO₂ comes out of the smoke stack of an average electricity-generating unit, it comprises only fourteen to fifteen percent of the concentration of the emissions.⁵⁰ While it is technically possible to transport and sequester that gas stream in its entirety, the process is cost-prohibitive.⁵¹ Storing the entire stream of emission, without concentrating and removing the CO₂, would result in transporting and storing at least eighty-five percent more volume than required for simply storing CO₂. Thus, it is necessary to capture and concentrate a pressurized stream of CO₂ for transportation.⁵²

The upfront costs of retrofitting an existing coal-fired power plant or constructing a new plant with the technology to capture, clean, and pressurize its emission stream for geologic storage are great.⁵³ The technology to capture CO₂ from a stream of emissions is used in multiple industrial sites for purification of other gases such as hydrogen and natural gas.⁵⁴ Currently, technology exists allowing for carbon capture in one of three ways: post-combustion,⁵⁵ pre-combustion,⁵⁶ and oxyfuel combustion.⁵⁷ Each has its benefits and costs, and use of one technology over another depends on site-specific characteristics.⁵⁸ Once an emission stream has been captured, it must be purified and compressed.⁵⁹ In its "supercritical"⁶⁰ state, after purification and compression, CO₂ acts neither entirely as gas nor as liquid and is transportable to the injection site.⁶¹

Anywhere from ten to forty percent additional energy is required to capture and compress a stream of CO₂.⁶² With this energy consumption additional to the amount used to produce electricity without carbon capture, total emissions would still be reduced by as much as eighty to ninety percent.⁶³ The additional energy required for capturing CO₂ emissions and preparing them for transportation and storage, then balances out with the emissions savings.⁶⁴ In the current regulatory scheme, there is no additional cost put on carbon emissions.⁶⁵ If that changes and a regulatory scheme is enacted which puts a cost on carbon,⁶⁶ then the economic scales may tip in favor of limiting the amount of CO₂ in emissions.⁶⁷ Other technological considerations, such as fuel source⁶⁸ and newer combustion technology,⁶⁹ reduce CO2 emissions in coal-fired power plants.⁷⁰ A combination of CCS technology and other...