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Congress hears testimony on GHG regs Proposed EPA rules place tight limits on carbon dioxide emissions from new coal-fired power plants, but are the limits practical? Alan Bailey Petroleum News
The publication in September by the Environmental Protection Agency, or EPA, of proposed new rules limiting the amount of carbon dioxide that new power stations can emit marked a key milestone in the Obama administration’s efforts to reduce U.S. carbon emissions. Having been unable to persuade Congress to pass carbon cap-and-trade legislation during his first term in office, the president is instead trying to achieve his greenhouse gas policy objectives through regulation of gas emissions.
Most climate scientists blame human-created carbon dioxide, mostly from the burning of fossil fuels, for on-going global warming. Scientists predict dire results if worldwide carbon emissions are not curbed.
But will the new EPA regulations spell the end of the construction of new coal-fired power stations in the United States? Or does technology exist to enable new facilities to meet the limits on carbon emissions? Under the proposed regulations a new coal-fired power plant would be limited to emissions of 1,100 pounds of carbon per megawatt of power generated, a number far below the emissions from a typical coal-fired plant.
Expert testimony On Oct. 29, in a joint hearing of two subcommittees of the House Committee on Science, Space and Technology, federal lawmakers listened to expert testimony on the thorny question of whether the EPA’s regulations are technically and economically feasible to implement.
In written testimony to the hearing Roger Martella, partner in the Environmental Practice Group of Sidley Austin, said that no coal-fired power plant in the world can come close to meeting the EPA’s proposed standard. Thus, as a policy ramification, the proposed standard would have the practical effect of “being as much an energy regulation as an environmental regulation,” given its practical impact of phasing out coal-fired power stations, Martella wrote.
There seems to be general agreement that the only means of meeting the new standard is to implement carbon capture and storage, or CCS, technology to sequester at least some of the carbon dioxide generated from the burning of coal. In its simplest form CCS involves using chemicals such as amines to scrub the gas from power plant exhaust — the gas is then injected into some form of underground reservoir. An alternative to exhaust scrubbing is the extraction of the carbon dioxide before burning by using the coal to manufacture hydrogen as fuel in a power station.
CCS is now also referred to as carbon capture, usage and storage, or CCUS, to encapsulate the possibility of improving the economics of the process by finding some industrial use for the carbon dioxide, perhaps using the gas to enhance oil recovery in an oil field or as a chemical manufacturing feedstock.
Commercial technology? Charles McConnell, executive director, energy and environment initiative, at Rice University, told the hearing that CCUS represents both an environmental solution to the carbon emissions problem and a business strategy for meeting EPA greenhouse gas regulations. But, while studies have verified that compliance with EPA’s new regulations will require the use of CCUS technology, there is no commercial CCUS technology available that can enable power stations to meet the EPA standard, McConnell said in written testimony to the hearing.
“The cost of current carbon dioxide capture technology is much too high to be commercially viable and places the technology at similar economic thresholds of alternative clean, carbon-free energy alternatives currently being subsidized,” McConnell wrote.
McConnell said that current technologies for the recovery of carbon dioxide at power plants increase the cost of generated electricity by about 80 percent and, while pipeline technology for transporting carbon dioxide to storage sites is mature, pipeline siting can prove problematic. There is also a lack of a proven track record for the sequestration of carbon dioxide in underground reservoirs, he wrote.
Still being evaluated “While injection of carbon dioxide into deep geologic storage formations is being evaluated, it has only been done successfully on a relatively small scale at a few sites around the globe,” McConnell wrote, adding that some forms of storage still face issues such as property rights and liability for any carbon dioxide leakage.
However, McConnell commented on the success that has been experienced in the sequestration of carbon dioxide for enhanced oil recovery in oil fields, a technique that he said has been practiced for more than 50 years.
McConnell also commented on Department of Energy funding assistance for CCUS research and development programs but said that at current funding levels affordable CCUS solutions “may be decades away.”
“The DOE’s coal research and development funding levels must be increased to enable the pursuit of demonstration projects to move transformational, low-cost CCUS technology from the laboratory to the commercial marketplace in a timely manner,” McConnell wrote.
Not cost competitive Richard Bajura, director of the National Research Center for Coal and Energy, West Virginia University, told the hearing in his written testimony that a state-of-the-art pulverized coal power plant may now output carbon at the rate of 1,800 pounds per megawatt hour of power generated. But established technologies using amines for carbon capture are not cost competitive for use in coal-fired power plants, he wrote.
“Using newer advanced technologies such as membranes or ionic liquids, or revised power cycles that minimize the steps required to separate and capture carbon dioxide, are ways to reduce costs,” Bajura wrote. “However, these are newer technologies that have not been demonstrated at commercial scales.”
Bajura also commented on the importance of integrating the operation of a carbon storage facility with the operation of the power plant with which it is associated, given the interdependence of the two operations. And carbon dioxide storage at the scales required for a major power plant has yet to be demonstrated, he wrote.
“Carbon dioxide injection studies into geologic reservoirs have only been carried out at scales of 10s of thousands of tons of carbon dioxide per site,” Bajura wrote. “For a full-scale operating plant, a million tons of carbon dioxide per year may be generated and would need to be injected to handle the plant’s output.”
Up-beat view Characterizing EPA’s proposed regulations as the beginning of CCS rather than the end of coal, Kurt Waltzer, managing director the Clean Air Task Force, an environmental non-profit, took a more up-beat view of the status of CCS technology. Given the construction of new coal plants with life expectancies in excess of 50 years, especially in developing countries such as China, the deployment of CCS technologies will be crucial to the worldwide management of carbon emissions, Waltzer wrote in his pre-filed testimony.
Moreover, carbon dioxide capture from power and industrial plants will be vital to the expanded use of carbon dioxide for oilfield enhanced oil recovery, he wrote.
Large CCS projects linked to enhanced oil recovery, capturing and storing millions of tons of carbon dioxide per year, first started to appear in the United States in the 1970s and 1980s, Waltzer wrote.
“Because the component pieces of what we call CCS systems have been in widespread and safe use, separately, for 40 years or more, they are more than adequately demonstrated to form the basis for an emissions standard for power plant combustion of fossil fuels,” he wrote. “Indeed the component parts of CCS systems are not only ‘adequately demonstrated,’ they are commercially available.”
Migration to CCS started The migration to CCS technology has already started and, with stronger regulatory drivers, will accelerate, Waltzer wrote, commenting that a coal to synthetic natural gas plant in North Dakota has been doing pre-combustion carbon capture since 2000, shipping carbon dioxide to Canada for enhanced oil recovery. And some coal-fired power stations that will use CCS technology for sequestering carbon dioxide underground are scheduled to go into operation, including a plant in Mississippi that is slated to go into operation in 2014 and a plant in Saskatchewan, Canada, with a planned startup in the spring of the same year, Waltzer wrote.
Several cost factors Waltzer said that the cost associated with the use of CCS technology depends on several factors, including the length of time over which developers could phase in the CCS implementation and the percentage of the carbon dioxide removed by the CCS process. The availability of an enhanced oil recovery application for the carbon dioxide also significantly impacts the cost.
According to an analysis by the Clean Air Task Force for power from a high-efficiency “supercritical” coal-fired power station, the use of CCS to sequester 50 percent of the generated carbon dioxide, with no phasing of implementation, would add 36 percent to the cost of the power. With revenue from enhanced oil recovery that cost increase would drop to 24 percent, dropping further to 13 percent in a phased implementation over 10 years, Waltzer wrote.
There are already about 4,000 miles of carbon dioxide pipeline carrying carbon dioxide to enhanced oil recovery locations, the technology for the underground injection of the gas has a 50-year track record for use, and natural gas companies already commonly use deep geologic structures to store natural gas, he wrote.
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