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Powering the planet: Chemical challenges in solar energy utilization

Lewis, Nathan S. and Nocera, Daniel G. (2006) Powering the planet: Chemical challenges in solar energy utilization. Proceedings of the National Academy of Sciences of the United States of America, 103 (43). pp. 15729-15735. ISSN 0027-8424.

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Global energy consumption is projected to increase, even in the face of substantial declines in energy intensity, at least 2-fold by midcentury relative to the present because of population and economic growth. This demand could be met, in principle, from fossil energy resources, particularly coal. However, the cumulative nature of CO2 emissions in the atmosphere demands that holding atmospheric CO2 levels to even twice their preanthropogenic values by midcentury will require invention, development, and deployment of schemes for carbon-neutral energy production on a scale commensurate with, or larger than, the entire present-day energy supply from all sources combined. Among renewable energy resources, solar energy is by far the largest exploitable resource, providing more energy in 1 hour to the earth than all of the energy consumed by humans in an entire year. In view of the intermittency of insolation, if solar energy is to be a major primary energy source, it must be stored and dispatched on demand to the end user. An especially attractive approach is to store solar-converted energy in the form of chemical bonds, i.e., in a photosynthetic process at a year-round average efficiency significantly higher than current plants or algae, to reduce land-area requirements. Scientific challenges involved with this process include schemes to capture and convert solar energy and then store the energy in the form of chemical bonds, producing oxygen from water and a reduced fuel such as hydrogen, methane, methanol, or other hydrocarbon species.

Item Type:Article
Additional Information:© 2006 by the National Academy of Sciences. Edited by Edward I. Solomon, Stanford University, Stanford, CA, and approved August 11, 2006 (received for review May 25, 2006). Published online on October 16, 2006, 10.1073/pnas.0603395103. We acknowledge sustained support from the U.S. Department of Energy (Office of Basic Energy Sciences) and the National Science Foundation (and in particular, Chemical Bonding Center CP-CP0533150) for basic research in renewable energy and for facilitating our ongoing perspective on global energy options. Author contributions: N.S.L. and D.G.N wrote the paper. The authors declare no conflict of interest. This article is a PNAS direct submission.
Issue or Number:43
Record Number:CaltechAUTHORS:LEWpnas06
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:9790
Deposited By: Tony Diaz
Deposited On:17 Mar 2008
Last Modified:03 Oct 2019 00:03

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