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| | Chapter 7 - The future of renewable biological energy systems |
 | | Biological energy production begins with the photosynthetic fixation of CO into biomass (starches, lignocellulosics, etc.) and is followed by conversion of biomass via various microbial processes to fuels (ethanol, methane, hydrogen, oils), as discussed in previous chapters. |
 | | Other overriding issues in the future of biological energy systems are the overall efficiencies of converting biomass to useful fuels, the economics of such processes, their environmental impacts, their competitiveness with thermochemical conversion processes for biomass (combustion, gasification), their resource potential, and, perhaps most important, their compatibility with evolving economic and political structures. |
 | | Although biomass energy systems are already competitive with fossil fuels in some specific cases, major expansion of renewable bioenergy will require not only advances in technology but also in economic accounting of their lower environmental and societal costs, compared to fossil fuels. |
| www.fao.org /docrep/w7241e/w7241e0i.htm (4538 words) |
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