Annual Energy Outlook 2006 with Projections to 2030 - Usinfo.org

Issues in FocusHistorically, the development of new technologies forlight-duty vehicles has been driven by the challenge ofmeeting increased demand for larger, quieter, morepowerful vehicles while complying with emissions,safety, and fuel economy standards. The auto industryhas met those challenges and, through technologicalinnovation, delivered larger, more powerfulvehicles with improved fuel economy.In 1980, the average new car weighed 3,101 pounds,had 100 horsepower, and averaged 24.3 miles per gallon.In 2004, the average new car weighed 3,454pounds (an 11-percent increase), had 181 horsepower(an 81-percent increase), and averaged 29.3 miles pergallon (a 21-percent increase). Improvements in newlight trucks (including sport utility vehicles) from1980 to 2004 have been even more profound: theiraverage weight has increased by 20 percent to 4,649pounds, their horsepower has increased by 91 percentto 231, and their average fuel economy has increasedby 16 percent to 21.5 miles per gallon [47].The majority of improvements in horsepower and fueleconomy for new light-duty vehicles have resultedfrom changes in conventional vehicle components,including fuel delivery systems, valve train design,aerodynamics, and transmissions. In 1980, almost allnew light-duty vehicles employed carburetors for fueldelivery; in 2004, all new light-duty vehicles used portfuel injection systems, which improve engine efficiencythrough very precise electronic control of fueldelivery. Advances have also been made in valve traindesign, improving efficiency by reducing enginepumping losses. In 1980, all engine designs used twovalves per cylinder; in 2004, engines with four valvesper cylinder were installed in 74 percent of new carsand 43 percent of new light trucks.Increases in light-duty vehicle horsepower and fueleconomy are projected to continue in the AEO2006cases at rates similar to their historical rates, whilevehicle weight remains relatively constant. For example,between 2005 and 2030 new car horsepowerincreases by 19 percent, to 215, in the reference case,while fuel economy increases by 15 percent to 33.8miles per gallon; and the horsepower of new lighttrucks increases by 14 percent, to 264, and fuel economyincreases by 23 percent to 26.4 miles per gallon,while their weight increases by 4 percent to 4,828pounds. Most of the improvements result from innovationsin conventional vehicle components.To project potential improvement in new light-dutyvehicle fuel economy, 63 conventional technologiesare represented in the Transportation Module. Thetechnologies are grouped into six vehicle system categories:engine, transmission, accessory load, body,drive train, and independent (related to safety andemissions). Table 13 summarizes the technologiesexpected to have significant impacts over the projectionperiod, the expected range of efficiency improvements,and initial costs.Engineering relationships among the technologiesare also modeled in the Transportation Module.The engineering relationships account for: (1)co-relationships, where the existence of one technologyis required for the existence of another; (2) synergisticeffects, reflecting the combined efficiencyimpact of two or more technologies; (3) supersedingrelationships, which remove replaced technologies;and (4) mandatory technologies, needed to meetsafety and emissions regulations. In addition to theengineering relationships, reductions in technologycost are captured as unit production increases orcumulative production reaches a design cyclethreshold.Technologies expected to show the greatest increasein market penetration, and thus the greatest impacton new car and light truck efficiency, include lightweightmaterials, improved aerodynamics, enginefriction reduction, improved pumps, and low rollingresistance tires (Figures 17 and 18). These technologiesrepresent the most cost-effective options forimproving fuel economy while meeting consumerexpectations for vehicle performance and comfort.The weight of new cars remains relatively constant asa result of increased market penetration of highstrengthlow-alloy steel (63 percent by 2030), aluminumcastings (24 percent by 2030), and aluminumbodies and closures (12 percent by 2030). Variablevalve timing and lift and camless valve actuation arealso expected to have a significant impact on new carefficiency, with installations increasing to approximately30 percent and 4 percent, respectively, in2030. The use of unit body construction in new lighttrucks increases from 23 percent in 2004 to 36 percentin 2030 as more sport utility vehicles and pickuptrucks are developed from car-based platforms.The efficiency of new light-duty vehicles also improveswith increased market penetration of hybridand diesel vehicles. Depending on the make andmodel, the incremental cost of a power-assistedhybrid vehicle (a “full hybrid”), currently estimatedat $3,000 to $10,000, decreases to between $1,500 and$5,400 in 2030 [48]. As a result, the penetration ofhybrid vehicles increases from 0.5 percent of newlight-duty vehicle sales in 2004 to 9.0 percent in 2030.50 Energy Information Administration / Annual Energy Outlook 2006