Study: Minnesota Can Achieve Transportation GHG Reduction Goals Using a Combination of Vehicle Efficiency, Low Carbon Fuels and Reduced VMT

22 July 2008

Minnesota LDV GHG emissions under different scenarios. The state’s 2015 and 2025 goals are represented by the horizontal dotted lines. Click to enlarge.

A team of University of Minnesota transportation and public policy researchers concluded that the state’s transportation sector can nearly meet its share of Minnesota’s greenhouse gas (GHG) emissions goals in 2015 and can exceed them in 2025 using a combination of strategies targeted to reduce fuel consumption, vehicle-miles traveled (VMT), and fuel carbon content.

Strong action on all three fronts is needed sooner rather than later, according to the findings of the report Reducing Greenhouse Gas Emissions From Transportation Sources in Minnesota from the Center for Transportation Studies (CTS) at the university.

The transportation sector produces about 24% of Minnesota’s total GHG emissions; the light-duty vehicle (LDV) fleet accounts for nearly two-thirds of this. Commercial vehicles powered by diesel engines create about 16%, with the remainder coming from aviation, rail, marine, and off-road vehicles.

The 2007 Minnesota Next Generation Energy Act established greenhouse gas (GHG) reduction goals of 15% by 2015, 30% by 2025, and 80% by 2050 compared with 2005. CTS received an appropriation from the Minnesota Legislature to assess public policy and technology options for reducing GHG from the transportation sector.

The researchers investigated solutions in three broad categories:

• Reduce vehicle fuel consumption per mile. Increasing efficiency by improving vehicle fuel economy (e.g., CAFE or carbon emission standards, incentives for more efficient vehicles) and by switching toward other modes (walk, bike, bus, light rail).

• Reduce fuel carbon content. Reducing GHG by substituting alternative fuels for gasoline and by increasing use of electric and plug-in hybrid vehicles while encouraging low-GHG electricity generation.

• Reduce vehicle miles traveled. Shifting land use and transportation infrastructure to reduce transportation energy consumption by increasing urban density and mass transit, encouraging non-vehicle transportation options, and reducing vehicle idling (e.g., trucks at truck stops, ships in port).

The analysis looked at two regulatory approaches to reduce fuel consumption per mile: the California CO₂ standards and the federal Corporate Average Fuel Economy (CAFE) standards. In 2025, assuming no further efficiency improvements past 2020 (the final year for each standard), CAFE standards could contribute about 66% and California standards about 80% of the transportation reduction goal.

The study also found that the study found that a feebate policy in Minnesota, if enacted with other Midwest states so that the fleet size would be comparable to California’s, could cut emissions significantly. A $180 feebate based on a 30 mpg pivot point would reduce LDV fleet-wide emissions by about 17% in 2016 (compared with 2002). This could contribute a third to half of Minnesota’s transportation reduction goal. Doubling the feebate to $360 produces the same reduction as the California standards, according to the analysis.

The combination of the $180 feebate program with the California standards cuts emissions 25% more than implementing the California standards alone—showing the benefit of combined policies.

On the fuels side, the study found that the lifecycle quality of the biofuel has a greater impact than the quantity blended with gasoline. In its evaluation, the study found that a scenario with 10% use of 100% cellulosic ethanol produced better GHG results than either E20 with corn ethanol, or corn E20 with the stover used to generate process heat.

If Minnesota adopts a low-carbon fuel standard requiring low-carbon biofuels and alternative fuels, the study projects that carbon emissions would fall 10% by 2020 and 12% by 2025. This policy could contribute 27% of Minnesota’s transportation reduction goals in 2015 and 40% in 2025.

Reducing vehicle miles traveled has a major effect on the state’s success in achieving the GHG reduction goals, but, the report noted, it is arguably the area with greatest uncertainty.

The research team studied a range of policies that reduce VMT, such as alternative travel modes, improved urban form and mixed land-use, population densification, pricing, telecommuting, pay-as-you-drive insurance, improved freight efficiency, and process alteration (for example, creating an office of sustainability in Mn/DOT). Depending on which policies are chosen, VMT could range widely. Each 1 percent reduction in VMT would contribute a 0.8 percent reduction in the transportation sector’s GHG emissions, holding all other factors constant.

Other conclusions of the report include:

• Vehicle and fuel policies are most effective when implemented across a broad base that includes other states.

• Mileage standards considerably higher than those being considered in this country are possible with today’s technology.

• The savings from buying a more fuel-efficient vehicle offset the cost of the added technology. Greater fuel efficiency benefits the economy and helps insulate consumers from rising gas prices.

• An important step in meeting the 2050 target is to develop infrastructure to shift the long-distance transport of freight and passengers to more efficient modes, such as rail.

Resources

• Reducing Greenhouse Gas Emissions From Transportation Sources in Minnesota