The future of fossil fuels

With today's energy technology, the world faces a stark choice between economic growth and a healthy environment. The accumulation of CO$_{2}$ in the atmosphere must stop, while energy services to a growing world population striving for a high standard of living must improve. New technologies must eliminate CO$_{2}$ emissions. Only carbon capture and storage can maintain access to fossil carbon reserves that by themselves could satisfy energy demand for centuries. Technologies for CO$_{2}$ capture at power plants and other large sources already exist. A new generation of efficient, clean power plants could capture its CO$_{2}$ and deliver it for underground injection or mineral sequestration. However, the remaining CO$_{2}$ emissions from distributed sources are too large to be ignored. Either hydrogen or electricity need to substitute for carbonaceous energy carriers, or CO$_{2}$ emissions must be balanced out by capturing an equivalent amount of carbon from the environment. Biomass growth offers one such option; direct capture of CO$_{2}$ from the air provides another. Carbon capture and storage technologies can close the anthropogenic carbon cycle and, thus, provide one possible avenue to a world that is not limited by energy constraints.