Capturing and storing most of the CO2 emissions from fossil fuel power plants in geological formations can become, if deployed on a very large scale within a few decades, one of a handful of principal strategies for mitigating climate change. Because the volume of CO2 requiring storage for an individual project and the associated area that must be dedicated to that storage have not been well appreciated, Socolow wrote a popular article in the July 2005 Scientific American, “Can We Bury Global Warming,” that contained a full page figure illustrating, to scale, the volume and area required for a 1000-megawatt coal plant, under plausible assumptions (Figure 16). About six million tons of CO2 are produced each year, or 360 million tons over the plant’s sixty-year lifetime. The associated volume of supercritical CO2 is three billion barrels (one-half cubic kilometer, or 350 billon tons). The area of dedicated storage below ground depends, of course, on the available aquifer volumes, but it also depends on the fraction of the pore space that can be filled by CO2, which is still a topic of research.
The article also sought to present a balanced view of risks and opportunities. Our intention is to promote early experience with full-scale, plant-lifetime CO2 capture and storage at large coal plants, with the goal of shortening the time before CO2 capture and storage is a feature of all new coal plants globally. We also are seeking to prepare the ground so that, from the outset, CO2 capture and storage is included in all plants producing synfuels from coal.