A majority of the carbon dioxide (CO2) generated by human activities comes from the use of fossil fuels as reliable sources of energy, helping us to maintain our current economy and quality of life. Many actions will be needed to reduce CO2 emissions. Options include conserving energy; improving the energy efficiency of our cars, appliances, and power plants; generating more electricity from nuclear and renewable energy sources; and implementing carbon capture and storage, or CCS, at power plants that burn fossil fuel.
CCS could substantially reduce CO2 emissions to the atmosphere. It would be most efficient when applied to large power plants and industrial facilities that produce large volumes of CO2. Using specialized processes and equipment, CO2 is captured, compressed, and transported to sites appropriate for safe, long-term geologic storage.
Underground storage entails injecting compressed CO2 into deep rock formations that are both physically and chemically stable; have an adequate storage space within the rock (porosity); and are covered by thick, impermeable rock formations (seals or cap rocks) that confine the CO2 at depths typically greater than 1 mile.