Transportation system impacts – including vehicle miles traveled (VMT), fuel use and cost of driving, and greenhouse gas (GHG) emissions – vary significantly across the scenarios. The land use patterns described in each scenario result in distinct differences in the rates of passenger auto use, measured as VMT, which in turn impacts fuel consumption, fuel cost, and emissions. (Refer to the appendix for specific policy-based assumptions about auto fuel economy and technology, and fuel composition and cost.)
“With over 12 billion vehicle miles traveled every year in Central Ohio, developing more of what we have seen in the past will only add to the current traffic congestion throughout Central Ohio. Creating more market driven, walkable, mixed used developments will allow for sustainable development without the added pressure of additional infrastructure to build and maintain.”—Holly Mattei, Executive Director at Fairfield County
Vehicle Miles Traveled (VMT)
VMT is calculated by applying assumptions about the distances people drive each year to projected population growth. These assumptions, which differ by place type, are calibrated to per-capita driving rates and modeling data from the Central Ohio region. This data, as well as national data sets, illustrate that per-capita VMT of both new and existing population vary based on the form of new growth*. For example, when a majority of new growth occurs as Compact or Urban development, over time most people – including those living in existing neighborhoods – will be able to drive less because more jobs, daily destinations, and services will be closer. Likewise, if a majority of new growth occurs as Standard development, many people will be likely to drive more, as workplaces and other destinations will grow farther apart.
The scenarios assume that requisite transportation investments go hand-in-hand with growth patterns, such that scenarios with a greater focus on Compact and Urban place type development would see increased transit, bicycle, pedestrian, streetscape, and livability investments. Conversely, scenarios dominated by Standard development would see larger budget outlays to highway and road expansion and maintenance.
Scenario results for VMT indicate a wide variation in passenger vehicle use related to the form of new growth. The consequence of putting more homes in dispersed patterns is high: The Past Trends scenario, which accommodates 87% of growth in auto-oriented Standard development, produces an average annual VMT of 8,470 per new person per year by 2050.
Annual Vehicle Miles Traveled (VMT) in 2050
Annual VMT Per Person in 2050
In total, residents of Central Ohio traveled about about 12 billion miles per year in their automobiles in 2010. In the Past Trends scenario, this rises to an annual VMT of 15.9 billion miles in 2050; for Planned Future, the total is 15.4 billion. VMT is held at about its 2010 level in the the Focused Growth scenario, at 12.0 billion (4 billion miles per year less than Past Trends). Maximum Infill results in an annual total of 11.1 billion miles, nearly 5 billion less than Past Trends. The difference between Past Trends and Focused Growth is equivalent to taking nearly 400,000 cars off Central Ohio’s roads each year – the same number of cars on the road every day in Central Ohio during the peak hour of the morning commute.
This is 4,000 miles more than the Focused Growth scenario (4,450 miles per capita), and 4,600 more than Maximum Infill (3,850 miles per capita). These figures can be compared to the 2010 region-wide average of about 6,600 miles per person.
*1 For a description of the RapidFire VMT modeling methodology, refer to the RapidFire Technical Summary, available at www.calthorpe.com/scenario_modeling_tools.
Automobile Fuel Use and Cost of Driving
Variations in passenger VMT lead to substantial differences in the amount of gas (or equivalent) used. These differences will vary depending on how efficient cars become. Assuming the same vehicle fuel economy for all scenarios, there would be substantial differences in fuel use due to land use-related VMT variations. By 2050, Past Trends would require 740 million gallons of fuel annually. Planned Future would require 27 million gallons less, Focused Growth would require 185 million gallons less, and Maximum Infill would require 227 million gallons less than the Past Trends scenario.
Cumulative Passenger Vehicle Fuel Consumption to 2050 (gallons gasoline equivalent)
Annual Passenger Vehicle Fuel Consumption to 2050 (gallons gasoline equivalent)
Reduced VMT and fuel use leads to lower costs for all households. When compared to Past Trends, Planned Future saves the average Central Ohio household $470 per year in driving costs in 2050 (including auto ownership, maintenance, and other driving-related costs); Focused Growth saves $3,200; and Maximum Infill saves $3,900 per year – significant savings that could be applied to housing and other essentials. For the entire region, the driving-related savings total $18.5 billion through 2050 in Focused Growth, and almost $23 billion in the Maximum Infill scenario.
Cumulative Fuel Costs to 2050 (2014 dollars)
Annual Driving Costs per New Household in 2050 (2014 dollars)*
*includes fuel, insurance, and maintenance associated with auto ownership
Greenhouse Gas (GHG) Emissions from Passenger Vehicles
GHG emissions from passenger vehicles are determined by VMT (related to land use patterns), vehicle fuel economy, and the carbon intensity of automobile fuel. Assuming the same rate of fuel emissions for all scenarios, there would be substantial differences in CO2e emissions (carbon dioxide equivalent, which includes the main forms of greenhouse gases). The land use-related variations in GHG are directly proportional to VMT and fuel use. By 2050, Past Trends would produce 6.7 million metric tons (MMT) of CO2e annually. Planned Future would produce 4% less; Focused Growth would produce 25% less, the equivalent of about 600,000 cars worth of emissions annually; and Maximum Infill would produce 30% less, the equivalent annual GHG emissions of about 730,000 passenger cars. When combined with the effects of more stringent vehicle and fuels policies, which would reduce the amount of fuel used and GHG emissions for every mile traveled, automobile-related emissions could be reduced even further.
Note that the transportation GHG emissions reported here are limited to tailpipe (tank-to-wheel) emissions. A more complete picture of emissions emerges in an analysis of full lifecycle (well-to-wheel) emissions, which take into account the emissions associated with generating fuel from various sources. The RapidFire model estimates both fuel combustion and full fuel lifecycle emissions.
Annual Transportation GHG Emissions in 2050 (MMT CO2e)
Annual Transportation GHG Emissions per Capita (lbs CO2e)