Our Commitment to Addressing Climate Change by Reducing Transportation’s Impact on the Environment

Year after year, the transportation sector has been the largest source of greenhouse gases (GHGs), accounting for 29 percent of total U.S. GHG in 20191. Thus, the U.S. Department of Transportation is committed to creating a more sustainable relationship with the environment. Here, at the Intelligent Transportation Systems (ITS) Joint Program Office (JPO), we have been researching how innovative ITS technologies can reduce transportation’s impact on the environment.

One such effort was the Applications for the Environment: Real-Time Information Synthesis (AERIS) Research Program, which aimed to encourage the development of technologies and applications that support a more sustainable relationship between transportation and the environment—primarily through fuel-use reductions and resulting emissions reductions. Over a 5-year period, the program defined transformative fuel-saving approaches using dedicated short-range communications-based connected vehicle and infrastructure applications in the 5.9 GHz band. It also demonstrated state-of-the-art modeling and analysis to better understand the potential environmental benefits offered by connected vehicles. Most notably, the AERIS Research Program developed the GlidePath prototype application—a first-of-its-kind use of a cooperative adaptive cruise control system that automatically communicates wirelessly with a traffic signal and controls a vehicle's speed in an eco-friendly manner. During testing, the GlidePath prototype reduced fuel consumption by 17 percent on average2. This pioneering work established a solid foundation for continued research and innovation involving variable signal timing, accommodating other vehicles in the intersection, and investigating multi-signal applications.

Building on the research needs identified for the AERIS Program’s Eco-Signal application, the ITS JPO and Federal Highway Administration funded the Traffic Optimization for Signalized Corridors (TOSCo) Project. The TOSCo system consists of a series of innovative applications designed to optimize traffic flow and minimize vehicle emissions on signalized arterial roadways. Vehicles equipped with TOSCo functionality use signal phase and timing and queue information from TOSCo-equipped infrastructure to automatically speed up or slow down ahead of an intersection to reduce the likelihood of idling. During the simulation modeling phase of the project, TOSCo vehicles showed positive impacts on fuel consumption and emissions3. The real-world testing and deployment phase of the TOSCo Project is currently underway, and the project is expected to run through at least March 2022.

The ITS JPO recognizes that the commitment to our environment is an ongoing effort. We are exploring additional research efforts focusing not only on safety of life and mobility improvements to transportation, but also on mitigating transportation’s impact on the environment. We are all in this together.

2 Altan, et al. “GlidePath: Eco-Friendly Automated Approach and Departure at Signalized Intersections,” IEEE Transactions on Intelligent Vehicles, Vol. 2, No. 4, December 2017.
3 https://rosap.ntl.bts.gov/view/dot/50734

Ken Leonard
ITS JPO Director

Posted 6/9/21