Eliminating carbon emissions from electric generation is only a partial step in the transition to carbonless energy systems. Further carbon reductions will require renewable fuel production, most likely hydrogen, given its universal applicability to all sectors of transportation. Fundamental energy balance indicates, however, that the overall costs of reducing emissions from transportation will likely be higher than reducing emissions from the utility sector. A kWh of renewable electricity delivered for end-use displaces at least 1.75 kWh of fossil fuel (natural gas). Alternatively that kWh of electricity would displace only 0.63 - 0.83 kWh of gas use though electrolytic hydrogen substitution in transportation. This basic factor is the underlying reason for the higher cost of carbon reduction in the transportation sector. Using solar electrolytic hydrogen, fueling 250 million passenger vehicles can reduce carbon emissions from 248 to 182 mmtC/yr at a cost of $850/tonneC. Displacing natural gas from freight transportation can reduce emissions to 90 mmtC/yr, increasing marginal cost only slightly to $950/tonneC, due to the lowered capacity factor of hydrogen production equipment driven by the solar patterns availability. Eliminating emissions from transportation completely requires displacing natural gas from aircraft with energy intensive liquid hydrogen, raising costs substantially to $1150/tonneC.
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Your Alternative Fuel Solution for Saving Money, Reducing Oil Dependency, and Helping the Planet. Ethanol is an alternative to gasoline. The use of ethanol has been demonstrated to reduce greenhouse emissions slightly as compared to gasoline. Through this ebook, you are going to learn what you will need to know why choosing an alternative fuel may benefit you and your future.