Environment

Automated Vehicle Technology Has the Potential to Smooth Traffic Flow and Reduce Greenhouse Gas Emissions

Almatrudi, Sulaiman
Parvate, Kanaad
Rothchild, Daniel
Vijay, Upadhi
Jang, Kathy
Bayen, Alexandre
2022

In an ideal world, all cars along a congested roadway would travel at the same constant average speed; however, this is hardly the case. As soon as one driver brakes, trailing cars must also brake to compensate, leading to “stop and go” traffic waves. This unnecessary braking and accelerating increases fuel consumption (and greenhouse gas emissions) by as much as 67 percent.1 Fortunately, automated vehicles (AVs) — even Level 2 AVs2 which are commercially available today — have the potential to mitigate this problem. By accelerating less than a human would, an AV with flow smoothing...

Considerations for Mitigating VehicleMiles Traveled under SB 743

Elkind, Ethan
Lamm, Ted
2018

Pursuant to Senate Bill 743 (Steinberg, 2013), which reformed the process for California Environmental Quality Act (CEQA) review of transportation impacts to align with greenhouse gas emissions reduction goals, the Governor’s Office of Planning and Research identified vehicle miles traveled (VMT) as the key metric to measure transportation impacts of new developments under CEQA.As a result, project developers will now have to reduce VMT to mitigate significant transportation impacts. While methods for reducing VMT impacts are well understood, implementing VMT reduction measures thatare...

Flexibility in California Transportation Funding Programs and Implications for More Climate-Aligned Spending

Segal, Katie
Elkind, Ethan
Lamm, Ted
2021

Flexibility in California Transportation Funding Programs and Implications for More Climate-Aligned Spending examines key features of the legislative authority for transportation planning and finance in California, including local option sales taxes for transportation, and assesses the amount of flexibility that current laws and practices allow for reprioritizing projects as problems and priorities change.

Review of Statewide Transportation Plans for California

Deakin, Elizabeth
Chow, Chun Ho
Son, Daisy
2021

California has adopted ambitious goals for its transportation systems. The state has pledged to reduce greenhouse gas(GHG) emissions by 40 percent compared to 1990 levels and by 80 percent by 2050, and has also committed to achieve carbon neutrality by 2045. With transportation a major emitter, substantial changes in transportation vehicles, fuels, operations, and user choices must be achieved to meet these goals. As pressing as climate change goals must be, other goals remain important. California has pledged to maintain its transportation infrastructure in a state of good repair, provide...

The Producer Surplus Associated with Gasolne Fuel Use in the United States

Sun, Yongling
Delucchi, Mark A.
Lawell, C.-Y. Cynthia L.
Ogden, Joan M.
2019

Estimating the producer surplus – the revenue above the average long-run cost – is an important part of social cost-benefit analyses of changes in petroleum use. This paper estimates the producer surplus associated with changes in gasoline fuel use in the United States, and then applies the estimates of producer surplus to two kinds of social cost-benefit analyses related to petroleum use: (1) estimating the wealth transfer from consumers to producers as a result of policies that affect oil use and oil imports to the US, and (2) comparing the actual average cost of gasoline with the...

Life-cycle Environmental Inventory of Passenger Transportation in the United States

Chester, Mikhail V
2008

Energy use and emission factors for passenger transportation modes typically ignore the total environmental inventory which includes vehicle non-operational components (e.g., vehicle manufacturing and maintenance), infrastructure components, and fuel production components from design through end-of-life processes. A life-cycle inventory for each mode is necessary to appropriately address and attribute the transportation sector’s energy and emissions impacts to reduction goals instead of allowing tailpipe emissions to act as indicators of total system performance.

The contributions...

Electric Two-Wheelers in China: Analysis ofEnvironmental, Safety, and Mobility Impacts

Cherry, Christopher R.
2007

Electric powered two-wheel bicycles, while extremely popular in China, have been recently banned by policy makers due to safety, congestion, and environmental concerns. This study investigates the tremendous growth of electric two wheel bicycles in China and compares and quantifies their environmental and safety impacts with the impacts of alternative modes of transportation, such as traditional bicycles, public transportation, or personal cars. The research also analyzes the benefits of electric two wheel bicycles, such as increased mobility and access to opportunities. Additionally, the...

An improvement on the end-of-life of High-speed rail rolling stocks considering CFRP composite material replacement

Rungskunroch, Panrawee
Kaewunreuen, Sakdirat
Shen, Zuo-Jun
2019

It is undeniably true that transportation systems positively impact human life but, the use of transportation systems also emits green house gasses in the environment which leads to global warming. In this day and age, various technologies are being combined with transportation systems, aimed at reducing the global impact of greenhouse gas emissions. The high-speed rail (HSR), which is well-known for low CO2emissions, has continually been improved, especially its model. In this study, the material replacement method is taken to account for a feasibility study on the next model of the HSR....

Impacts of Shared Mobility

Shaheen, Susan, PhD
Cohen, Adam
2018

Shared mobility modes have reported a number of environmental, social, and transportation-related impacts. Several studies have documented the reduction of vehicle usage, ownership, and vehicle miles traveled (VMT). Cost savings and convenience are frequently cited as popular reasons for shifting to a shared mode. Shared modes can also extend the catchment area of public transit, potentially playing a pivotal role in bridging gaps in existing transportation networks and encouraging multi-modality by addressing the first-and-last mile issue related to public transit access (1). Shared...

Shared Mobility Policies for California

Shaheen, Susan, PhD
Cohen, Adam
2018

In recent years, economic, environmental, and social forces have quickly given rise to the “sharing economy,” a collective of entrepreneurs and consumers leveraging technology to share resources, save money, and generate capital. Shared mobility—the shared use of a vehicle, bicycle, or other low-speed travel mode—is an innovative transportation strategy that enables users to have short-term access to a transportation mode on an as-needed basis. Business-to-consumer services, such as Zipcar and car2go, and peer-to-peer carsharing and shared ride services, such as Getaround, Turo, Lyft, and...