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Title: Nuclear Energy for a Low-Carbon-Dioxide-Emission Transportation System with Liquid Fuels

Abstract

The two major energy challenges for the United States are to replace crude oil in our transportation system and reduce greenhouse gas emissions. A multilayer strategy to replace oil using nuclear energy and various carbon sources (fossil fuels, biomass, or air) is described that (a) allows the continued use of liquid fuels (ethanol, gasoline, diesel, and jet fuel) in the transport sector, (b) does not require major changes in lifestyle by the consumer, and (c) ultimately eliminates carbon dioxide emissions from the transport sector. Nuclear energy is used to provide electricity, heat, and ultimately hydrogen, with the hydrogen produced by either electrolysis or more advanced thermochemical production methods. In the near term, nuclear energy can provide low-temperature heat (steam) for ethanol production and electricity for transportation. Midterm options include low-temperature heat and limited quantities of hydrogen for processing cellulosic biomass into liquid fuels (ethanol and lignin-derived hydrocarbons) and providing high-temperature heat for (a) traditional refining and (b) underground oil production and refining. In the longer term, biomass becomes the feedstock for liquid-fuels production, with nuclear energy providing heat and large quantities of hydrogen for complete biomass conversion to hydrocarbon fuels. Nuclear energy could be used to provide over half themore » total energy required by the transportation system, and the use of oil in the transport sector could potentially be eliminated within several decades.« less

Authors:
 [1]
  1. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Nuclear Energy (NE)
OSTI Identifier:
958841
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Nuclear Technology; Journal Volume: 164; Journal Issue: 3
Country of Publication:
United States
Language:
English
Subject:
02 PETROLEUM; 08 HYDROGEN; 09 BIOMASS FUELS; 29 ENERGY PLANNING, POLICY AND ECONOMY; 32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION; AIR; BIOMASS; CARBON DIOXIDE; CARBON SOURCES; ELECTRICITY; ELECTROLYSIS; ETHANOL; GASOLINE; GREENHOUSE GASES; HYDROCARBONS; HYDROGEN; LIQUID FUELS; NUCLEAR ENERGY; PETROLEUM; PROCESSING; PRODUCTION; REFINING; STEAM; TRANSPORT; TRANSPORTATION SYSTEMS

Citation Formats

Forsberg, Charles W. Nuclear Energy for a Low-Carbon-Dioxide-Emission Transportation System with Liquid Fuels. United States: N. p., 2007. Web.
Forsberg, Charles W. Nuclear Energy for a Low-Carbon-Dioxide-Emission Transportation System with Liquid Fuels. United States.
Forsberg, Charles W. Mon . "Nuclear Energy for a Low-Carbon-Dioxide-Emission Transportation System with Liquid Fuels". United States. doi:.
@article{osti_958841,
title = {Nuclear Energy for a Low-Carbon-Dioxide-Emission Transportation System with Liquid Fuels},
author = {Forsberg, Charles W},
abstractNote = {The two major energy challenges for the United States are to replace crude oil in our transportation system and reduce greenhouse gas emissions. A multilayer strategy to replace oil using nuclear energy and various carbon sources (fossil fuels, biomass, or air) is described that (a) allows the continued use of liquid fuels (ethanol, gasoline, diesel, and jet fuel) in the transport sector, (b) does not require major changes in lifestyle by the consumer, and (c) ultimately eliminates carbon dioxide emissions from the transport sector. Nuclear energy is used to provide electricity, heat, and ultimately hydrogen, with the hydrogen produced by either electrolysis or more advanced thermochemical production methods. In the near term, nuclear energy can provide low-temperature heat (steam) for ethanol production and electricity for transportation. Midterm options include low-temperature heat and limited quantities of hydrogen for processing cellulosic biomass into liquid fuels (ethanol and lignin-derived hydrocarbons) and providing high-temperature heat for (a) traditional refining and (b) underground oil production and refining. In the longer term, biomass becomes the feedstock for liquid-fuels production, with nuclear energy providing heat and large quantities of hydrogen for complete biomass conversion to hydrocarbon fuels. Nuclear energy could be used to provide over half the total energy required by the transportation system, and the use of oil in the transport sector could potentially be eliminated within several decades.},
doi = {},
journal = {Nuclear Technology},
number = 3,
volume = 164,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
  • Abstract not provided.
  • Thermodynamic, achievable, and realistic efficiency limits of solar-driven electrochemical conversion of water and carbon dioxide to fuels are investigated as functions of light-absorber composition and configuration, and catalyst composition. The maximum thermodynamic efficiency at 1-sun illumination for adiabatic electrochemical synthesis of various solar fuels is in the range of 32–42%. Single-, double-, and triple-junction light absorbers are found to be optimal for electrochemical load ranges of 0–0.9 V, 0.9–1.95 V, and 1.95–3.5 V, respectively. Achievable solar-to-fuel (STF) efficiencies are determined using ideal double- and triple-junction light absorbers and the electrochemical load curves for CO 2 reduction on silver and coppermore » cathodes, and water oxidation kinetics over iridium oxide. The maximum achievable STF efficiencies for synthesis gas (H 2 and CO) and Hythane (H 2 and CH 4) are 18.4% and 20.3%, respectively. Whereas the realistic STF efficiency of photoelectrochemical cells (PECs) can be as low as 0.8%, tandem PECs and photovoltaic (PV)-electrolyzers can operate at 7.2% under identical operating conditions. Finally, we show that the composition and energy content of solar fuels can also be adjusted by tuning the band-gaps of triple-junction light absorbers and/or the ratio of catalyst-to-PV area, and that the synthesis of liquid products and C 2H 4 have high profitability indices.« less
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  • Thermodynamic, achievable, and realistic efficiency limits of solar-driven electrochemical conversion of water and carbon dioxide to fuels are investigated as functions of light-absorber composition and configuration, and catalyst composition. The maximum thermodynamic efficiency at 1-sun illumination for adiabatic electrochemical synthesis of various solar fuels is in the range of 32–42%. Single-, double-, and triple-junction light absorbers are found to be optimal for electrochemical load ranges of 0–0.9 V, 0.9–1.95 V, and 1.95–3.5 V, respectively. Achievable solar-to-fuel (STF) efficiencies are determined using ideal double- and triple-junction light absorbers and the electrochemical load curves for CO 2 reduction on silver and coppermore » cathodes, and water oxidation kinetics over iridium oxide. The maximum achievable STF efficiencies for synthesis gas (H 2 and CO) and Hythane (H 2 and CH 4) are 18.4% and 20.3%, respectively. Whereas the realistic STF efficiency of photoelectrochemical cells (PECs) can be as low as 0.8%, tandem PECs and photovoltaic (PV)-electrolyzers can operate at 7.2% under identical operating conditions. Finally, we show that the composition and energy content of solar fuels can also be adjusted by tuning the band-gaps of triple-junction light absorbers and/or the ratio of catalyst-to-PV area, and that the synthesis of liquid products and C 2H 4 have high profitability indices.« less
  • Thermodynamic, achievable, and realistic efficiency limits of solar-driven electrochemical conversion of water and carbon dioxide to fuels are investigated as functions of light-absorber composition and configuration, and catalyst composition. The maximum thermodynamic efficiency at 1-sun illumination for adiabatic electrochemical synthesis of various solar fuels is in the range of 32–42%. Single-, double-, and triple-junction light absorbers are found to be optimal for electrochemical load ranges of 0–0.9 V, 0.9–1.95 V, and 1.95–3.5 V, respectively. Achievable solar-to-fuel (STF) efficiencies are determined using ideal double- and triple-junction light absorbers and the electrochemical load curves for CO 2 reduction on silver and coppermore » cathodes, and water oxidation kinetics over iridium oxide. The maximum achievable STF efficiencies for synthesis gas (H 2 and CO) and Hythane (H 2 and CH 4) are 18.4% and 20.3%, respectively. Whereas the realistic STF efficiency of photoelectrochemical cells (PECs) can be as low as 0.8%, tandem PECs and photovoltaic (PV)-electrolyzers can operate at 7.2% under identical operating conditions. Finally, we show that the composition and energy content of solar fuels can also be adjusted by tuning the band-gaps of triple-junction light absorbers and/or the ratio of catalyst-to-PV area, and that the synthesis of liquid products and C 2H 4 have high profitability indices.« less
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