Carbon capture and storage (CCS) is widely believed to be an important tool in helping to reduce CO2 emissions from anthropogenic sources. CCS technology development aims to reduce the approximately 20–25% imposed electrical load and 40–60% cost of electricity (COE) increase imposed by near-term CCS technologies on coal-fired power plants. Although next-generation technologies are being developed and tested in the laboratory and in small pilot units on coal-fired power plants, aqueous amines are now deployed at coal-fired power plants on a commercial scale.
At the same time, EPA has proposed repealing the Clean Power Plan that placed limits on CO2 emissions from coal- and natural-gas-fired power plants (40CFR Part 60). The United States has also announced withdrawal from the Paris Accords on reducing greenhouse gas emissions. In the United States, the price of natural gas continues to be at historic lows, and given the environmental pressures on coal-fired units, there is a shift toward increasing reliance on natural gas instead of coal for power production. This shift is significant because CO2 emissions from natural-gas-fired power plants are about one-half those of coal-fired power plants—reducing the net emissions from the power sector. Indeed, the United States has reduced its CO2 emissions mostly because of the shift to natural gas in power production. Because of these factors and the general lack of international action on reducing greenhouse gas emissions, the urgency for CCS on power plants has been significantly reduced in recent years. However, under most regulatory scenarios being considered, CCS will also eventually be required on natural-gas-fired power plants—but little research is being conducted on natural gas CCS. It is reasonable to expect that the technologies that capture CO2 from coal-fired power plants should also work on natural-gas-fired power plants, except that the efficiencies, performance, and costs have been explored only at a high level.
This report provides an update on the development trends in post-combustion CO2 capture technologies. EPRI reviewed the literature for carbon capture technologies and applied filtering criteria to identify those with potential to reduce the energy and cost of capture. In some instances, EPRI has supported the development in collaboration with the Department of Energy’s CO2 capture program. EPRI’s work spans a range of activities, including molecular and process simulations, experimental support, and economic evaluation studies.