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The automotive infrastructure in the US consists of 250 million vehicles. We shall see below that it takes a long time to replace this infrastructure. Let’s develop a model to see how gas mileage improves with the introduction of new hybrid technology.
General Growth Assumptions:
The total number of all vehicles grows by about 1% a year to accommodate new drivers. Annual new car sales consists of about 7% of total vehicles. Total gas usage (116 billion gals/yr) results from an average of 12,000 miles driven per year with a 20 mpg fleet average. Use known data for number of existing hybrids and introduction volumes of EREVs. Assume hybrid and EREV sales have a mileage of 40 and 80 (with an improvement rate in 22 years to 140) mpg, respectively, and volumes grow at 25%/year after known production introduction volumes. Modify growth rate to keep total vehicles sold per year at max 7% annual rate. Assume that after 10 years hybrids and EV have a 7% wearout replacement rate. Assume new ICE vehicles have a mileage of 25 mpg and improve at 1.5%/yr. Model from 2008 to 2038 and check/modify results for consistency.
See attachment.
The results show that it will take 20 years for EREV sales to improve fleet mileage by 10% and 25 years for to replace half of ICE engines with alternative technology engines. At that time improvements in vehicle technology will reduce gas consumption from present levels by 10%.
Conclusion:
Because of the huge number of vehicles presently in use and slow rate of hybrid introduction, it will take a long time to replace the existing ICE infrastructure. Clearly, to get timely improvement in dependence on foreign oil, we must use another strategy such as an increase methanol and domestic fuel production.
General Growth Assumptions:
The total number of all vehicles grows by about 1% a year to accommodate new drivers. Annual new car sales consists of about 7% of total vehicles. Total gas usage (116 billion gals/yr) results from an average of 12,000 miles driven per year with a 20 mpg fleet average. Use known data for number of existing hybrids and introduction volumes of EREVs. Assume hybrid and EREV sales have a mileage of 40 and 80 (with an improvement rate in 22 years to 140) mpg, respectively, and volumes grow at 25%/year after known production introduction volumes. Modify growth rate to keep total vehicles sold per year at max 7% annual rate. Assume that after 10 years hybrids and EV have a 7% wearout replacement rate. Assume new ICE vehicles have a mileage of 25 mpg and improve at 1.5%/yr. Model from 2008 to 2038 and check/modify results for consistency.
See attachment.
The results show that it will take 20 years for EREV sales to improve fleet mileage by 10% and 25 years for to replace half of ICE engines with alternative technology engines. At that time improvements in vehicle technology will reduce gas consumption from present levels by 10%.
Conclusion:
Because of the huge number of vehicles presently in use and slow rate of hybrid introduction, it will take a long time to replace the existing ICE infrastructure. Clearly, to get timely improvement in dependence on foreign oil, we must use another strategy such as an increase methanol and domestic fuel production.
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