GREENHOUSE GAS REDUCTION TECHNOLOGIES FOR POWER GENERATION

• Jurisdiction: United States

Climate Change Law and Regulations: Planning for a Carbon-Constrained Regulatory Environment
(Jan 2015)
CHAPTER 9B
GREENHOUSE GAS REDUCTION TECHNOLOGIES FOR POWER GENERATION
Michael J. Nasi
Jacob Arechiga
Partner
Jackson Walker L.L.P.
Austin, Texas

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MICHAEL J. NASI is a partner with Jackson Walker L.L.P. in Austin, Texas, where he practices environmental and energy law. Mr. Nasi secures environmental permits for and is active in state and federal policy development on behalf of several energy industries. Mr. Nasi has been practicing before state and federal environmental and energy agencies and appellate courts, as well as the Texas Legislature, for more than 20 years. Mike currently represents rural electric cooperatives and other electric generation interests in ongoing EPA proceedings and appeals pending before the D.C. Circuit Court of Appeals and the Supreme Court of the United States. Mike is the Immediate Past-Chair of the State Bar of Texas Environmental and Natural Resources Law Section and is a tireless advocate for Texas Water funding as Secretary of the Board for H2O for Texas. Mike is an invited speaker at energy and environmental conferences across the country and has been published several times as well (for a detailed list, see www.jw.com/mnasi). He is consistently recognized on several "Who's Who" and "Best Lawyer" lists and, in 2010, was honored by Environmental Law 360 as one of the "Top 10 Environmental Attorneys in America Under 40." In addition to being active along with his wife and three children in his church and youth sports programs. Mr. Nasi serves as the Vice-Chair and Development Director for the Central Texas Salvation Army Advisory Board; He received his J.D. from the University of Houston Law Center, and his B.A. from the University of Texas at Austin.

Strategies and Technologies Available to Control Greenhouse Gases

GHG Reduction Technologies for Power Generation

I. Introduction

According to the International Energy Agency, demand for electricity is expected to increase by almost 80% by 2040.¹ Demand will grow at a faster pace in the developing world; for example, sub-Saharan Africa is expected to quadruple its electricity supply by 2040.² In order to meet this rising demand, including in countries such as China, "[e]conomic growth...needs more energy than nuclear, gas, oil and renewables can supply."³

Developing sufficient supplies to support this dramatic increase in demand will be a daunting task. An even more daunting task is sorting out what fuels can and will be used to meet that demand in light of the critical role that reliable and affordable energy plays in the quality of the human life and the health of the global economy. Myopic energy plans that focus on "silver bullet" technologies to solve the world's electricity needs have no place in a serious conversation about how to make sure the Earth's billions of citizens have access to affordable energy to improve their existence on this planet.

We will need an "all of the above" strategy that is not just a political talking point but a technological reality. Based on concerns with conventional pollutants and climate change, most nations are working to develop a diverse portfolio of electricity resources and technologies with a heavy emphasis on renewable and nuclear energy. Moreover, natural gas-combined cycle (NGCC) generation will continue to grow as sources of natural gas and evolving technologies like hydraulic fracturing and horizontal drilling continue to unlock new sources of natural gas.

Given global economic and resource realities, however, it is folly to suggest that the world can or should do without coal. Coal is too abundant in the developing nations that need affordable energy the most to theorize about how they can or should avoid its use. They will use it - just as China, India, and the ASEAN⁴ countries have used it at dramatic rates and with dramatic positive impacts on their ability to reduce poverty and infant mortality while increasing life expectancy, along with several quality of life indicators.

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So, the question is not whether the world will use coal - the question is how. In light of this reality, this paper provides an in-depth discussions of "inside the fence" strategies for emissions control and environmental compliance at coal-fired power plants, as these are arguably the most important technologies being developed relevant to electricity generation, especially if global carbon mitigation is the goal. In the short-term, heat rate improvements and other efficiency measures can be deployed to mitigate carbon emissions inside the fence of coal and gas plants, but the key to significant worldwide carbon mitigation is carbon capture, utilization and storage (CCUS).

Put simply, if you prioritize reducing manmade greenhouse gas emissions, then your absolute priority for carbon policy should be the commercialization and global proliferation of large-scale CCUS. The scale of global electricity demand, the relative abundance and affordability of coal, and the fact that both coal and natural gas have significant carbon emissions makes CCUS a critical element of any realistic global carbon mitigation strategy so it will be discussed at length below. Even if you are not convinced that managing mankind's contributions to climate change are scientifically warranted, CCUS should remain a very attractive option given the dramatic enhanced oil recovery (EOR) potential that exists which could serve to both meet international demand for oil and improve North American energy security.

II. Inside the Fence Strategies and Limitations

Coal has been used to produce energy in developed nations for hundreds of years, providing fuel for the Industrial Revolution and fundamentally changing the global economy. Although coal is the fuel most relied upon for electric generation in the United States, coal is not controlled solely by developed nations. Rather, it is widely distributed across the globe among developed and developing countries alike, which means that developing nations will insist upon and, perhaps, deserve the right to use it to produce electricity they will need to improve their quality of life. To put things in context, in 2013, China's coal demand growth (196 million tonnes [Mt]) was actually larger than global growth (188 Mt).⁵ India is on China's heels, expected to become the second-largest coal consumer in the word in the next 5 years, with projected annual growth of 5%.⁶

There are few energy-environmental debates as important to the global economy and the global environment as fossil-fueled electric generation and the ability to capture and geologically store carbon captured from the use of coal and, where appropriate, use that carbon for enhanced oil recovery. Although pre-combustion technologies such as gasification are in the running to become the backbone of the next-generation fleet of coal-fueled power plants, robust and efficient post-combustion technologies have the distinct benefit of being able to be bolted onto the existing fleet of carbon fuel-fired power plants. The existing fleet has thirty to sixty years of useful life remaining, and these plants cannot be completely redesigned and reengineered to employ pre-combustion capture technology. Therefore, commercial post-combustion carbon capture technology is as important, if not more important, than commercialization of pre-combustion gasification technologies.

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Heat Rate Improvements can achieve modest reductions in the carbon emission rates of fossil-fueled power plants but many such efficiencies have already been achieved, as discussed further in Appendix A ("Flaws with Inside the Fence Heat Rate Improvement Assessment in EPA's Proposed 111(d) Clean Power Plan"). The focus of this discussion will instead be on emerging carbon capture and sequestration technologies. Four specific carbon capture technologies are discussed below. The discussion will then shift to the sequestration side of the equation, with major emphasis on enhanced oil recovery and a final discussion of an innovative approach to large scale, long-term off-shore carbon utilization and storage.

A. Pre-Combustion Carbon Capture Technologies

1. Integrated Gasification Combined Cycle

The basic technology used for coal gasification dates back to the 1800s, where gasification facilities produced a product called town gas or coal gas. Today, the primary product of most gasification technologies is known as synthesis gas or syngas. Gasification works by heating and partially combusting a carbon-based fuel, e.g., coal, petroleum coke, petroleum, biofuels, or biomass, under pressure and in an environment with carefully controlled oxygen levels. Under these conditions, the fuel undergoes a chemical reaction as the components of the fuel break down, releasing hydrogen and carbon monoxide. The hydrogen and carbon monoxide are the two key constituents of syngas, which is an intermediary to the production of synthetic natural gas.

After the syngas has been produced, the CO2 can be separated from the syngas stream and permanently sequestered or used in an enhanced oil recovery or other beneficial application. A number of technologies are in development to extract CO2 from the syngas stream, including scrubbing with chemical solvents and sorbents and the use of physical membranes. After CO2 removal, the syngas that has been produced can either be used as fuel for a combustion turbine or converted into methane in a process called methanation to produce synthetic natural gas (SNG). Either syngas or SNG can be combusted to produce electricity in a combined cycle gas turbine (the "CC" of "IGCC").

Although not an IGCC plant (because there is not a combined cycle gas turbine involved), one of the earliest and most notable coal gasification-based chemical plants in the United States is owned and operated by Eastman...