Mark Twain, it is claimed, observed that everybody complains about the weather, but nobody does anything about it. A modern-day Twain might remark that everybody talks about climate change, but nobody is taking serious action. One big reason is economics. Reducing the buildup of carbon dioxide in the atmosphere—the major human-based driver of climate change—requires an expensive shift away from coal and oil as our prime sources of energy. Or it requires costly technology to capture CO2 as industry emits it and then store the gas where it will stay put for centuries to come.
Yet what if a technology could economically do both: produce large amounts of energy and significantly reduce greenhouse gas emissions? And what if that technology fit seamlessly into the country's existing industrial infrastructure? This scenario could become reality along the U.S. Gulf Coast. Because of a special geologic situation there, a huge amount of CO2 could be stored several kilometers underground in hot, salty fluid called brine, and the storage procedure itself would produce a vast amount of methane for fuel, as well as usable heat. Neither the storage nor the production of methane or of geothermal energy is economical on its own. Yet new calculations show that when the processes are combined in a closed-loop system, they could pay off handsomely in the U.S. and elsewhere.