Closing the Carbon Loop and Burying Global Warming

Kurt Zenz House, Research Assistant in Earth and Planetary Sciences, Harvard University

Friday, September 28, 2007, 3:30pm

Spanos Auditorium

Download Audio
MP3 (26 MB)


The continued combustion of fossilized carbon to provide work and heat is inevitable. Even with dramatic growth in alternative energy use and energy efficiency fossilized carbon will remain the dominant energy source over the next century. The combustion of fossil fuels is causing the concentration of atmospheric CO2 to rise, which may result in dangerous changes to the Earth's climate system. Therefore, stabilizing the concentration of atmospheric CO2 to avoid further changes to Earth's climate requires developing the capability to capture CO2 from large point sources and store it safely away from the atmosphere. Significant work on the storage of captured anthropogenic CO2 in terrestrial geologic storage is underway. Because of the subsurface pressure-temperature profile of terrestrial storage sites, however, CO2 stored in these reservoirs is buoyant. As a result, a portion of the injected CO2 can escape if the reservoir is not appropriately sealed. Our research, however, indicates that CO2 injected into deep-sea sediments below ~3 km of water and a few hundred meters of sediment is permanently stored due to a combination of gravity and chemistry. At the high pressures and low temperatures common in deep-sea sediments, liquid CO2 can be denser than the surrounding pore-water. In addition, at these conditions immobile CO2 -hydrate crystals become stable. The total CO2 storage capacity of deep-sea sediments within the 200-mile economic zone of the U.S. coastline is enormous, capable of storing thousands of years of current U.S. CO2 emissions.

About the Speaker

Kurt Zenz House is currently a Ph.D. candidate at Harvard University where he is researching methods of capturing and permanently storing anthropogenic carbon dioxide. The goal of his work is to develop technology that reduces the quantity of carbon dioxide that is emitted into the atmosphere per unit of useful work generated by the combustion of fossil carbon and to ensure that the captured carbon dioxide remains permanently stored. Prior to matriculating to Harvard for his graduate studies, Kurt worked as a corporate consultant with Bain & Company, Inc. At Bain, Kurt helped develop corporate strategies for several Fortune 500 companies as well as several companies in earlier stages of development. Kurt holds a bachelor's degree in Physics from the Claremont Colleges in Southern California, he hold a master's degree in Geoscience from Harvard University, and he is currently completing his doctoral studies at Harvard University.