The U.S. Energy Department's National Renewable Energy Laboratory (NREL) formed a partnership with the Colorado Department of Transportation (CDOT) to help support the state's $20 million RoadX transportation program. The partnership kicks off the lab's broader Sustainable Mobility Initiative.

NREL says its Sustainable Mobility Initiative approaches transportation as an integrated system, where travelers and transportation resources are viewed as a dynamic network that can be used to optimize mobility and reduce related energy consumption and emissions. NREL says it will draw on research capabilities now consolidated under its Sustainable Mobility program to offer approaches that support CDOT's RoadX program. It says that the program is a “transformative plan that reimagines transportation in Colorado as a crash-free, technologically advanced system.”

Momentum for Efficient Mobility

NREL's Transportation and Hydrogen Systems Center (THSC) Director Chris Gearhart says that historically, sustainable transportation research has focused on making individual vehicles more fuel efficient. "But that focus is evolving to also include systems of connected vehicles," he says. "Emerging technologies now make vehicle-to-vehicle information exchange possible, and travelers are connected by ubiquitous smartphones. Data collected via these technologies help us understand how drivers and travelers make decisions—and we use that information to steer our in-lab research toward better solutions."

The shift to a more connected mobility system requires a different set of players. In collaboration with automakers, information providers, and federal and state agencies, NREL is combining its expertise in vehicle-to-grid integration, data analysis, and vehicles and fuels research with vehicle automation, behavioral science, and urban science to approach sustainable transportation as a network of travelers, services, and environments.

Deployment of advanced transportation technology is no longer dependent on one group or industry. Image source: NREL/Warren Gretz.Deployment of advanced transportation technology is no longer dependent on one group or industry. Image source: NREL/Warren Gretz.NREL says that with electric vehicle companies such as Tesla, tech startups, and information technology giants including Google and Verizon, deployment of advanced transportation technology is no longer dependent on one group or industry. Growing collaborations between Detroit and Silicon Valley generated buzz at the 2016 Consumer Electronics Show in January, where several automakers announced their commitments to advanced vehicle automation features, in addition to partnerships with rideshare companies that offer on-demand transportation options.

A decade ago, the dominant view on vehicle automation was that it probably would take another 50 years to reach the marketplace. NREL says that breakthrough vehicle technologies and ride-sharing business models are changing the mobility system to one that's multi-disciplinary, integrated and evolving.

With increased automation and advanced sensors, intelligent vehicles can more effectively synchronize movements to avoid hazards, streamline traffic flow and reduce congestion and the risk of accidents, NREL says. Automated features such as parking assist and collision avoidance are becoming standard even in conventional vehicles. With the growing popularity of on-demand and rideshare services such as Uber, Lyft and Car2Go, the mobility landscape is shifting from one “dominated by private vehicle ownership to a rich mixture of auto-free or auto-light lifestyles, viewing mobility as a service,” NREL says.

The U.S. Department of Transportation has spearheaded a number of vehicle automation and connectivity initiatives, and announced in 2014 that vehicle-to-vehicle communications technology will soon be required for all light vehicles. The agency's Connected Vehicle Safety Pilot and Smart Cities Challenge are investigating additional safety and driver convenience benefits of automation.

"That's a significant distinction from our Sustainable Mobility push," says Gearhart. "These other efforts have barely touched on the technologies' energy efficiency potential."

Research to Support Colorado's Plan

The escalating pressures of a modern transportation system will most effectively be put to test in urban settings. NREL/Walter Marks.The escalating pressures of a modern transportation system will most effectively be put to test in urban settings. NREL/Walter Marks.CDOT is one of several public agencies working with NREL to deliver energy savings through connectivity and automation, while also enhancing safety and mobility. The Energy Department's Office of Energy Efficiency and Renewable Energy (EERE) is leading the development of a Systems and Modeling for Accelerated Research in Transportation (SMART) Mobility framework, an early-stage multi-lab consortium that approaches transportation as a collection of mobility systems. The Energy Department's Advanced Research Projects Agency-Energy (ARPA-e) Travel Response Architecture using Novel Signaling for Network Efficiency in Transportation (TRANSNET) project is looking at ways to minimize energy consumption in personal transportation, without major changes to infrastructure or vehicle technology.

The RoadX program plans to deploy advanced technology to reduce the cost of transporting goods, improve safety and alleviate congestion across Colorado's major transportation corridors. NREL will provide CDOT with systems-level expertise to help realize the state’s vision for next-generation mobility.

CDOT will rely on NREL's integrated transportation research capabilities, including knowledge of the technology required to connect travelers, vehicles, the grid, and the built environment; laboratories with the facilities needed to assess system interfaces; models for intelligent vehicles and interoperable systems; one of the nation's largest repositories of transportation big data and the analysis experts to interpret it; and insight into the impacts of traveler decision-making patterns and the urban environment.

NREL says that one of its roles will be to identify “meaningful insights” from the data collected via CDOT's traffic probes and cameras, public transit records, travelers' smartphone applications, and advanced vehicle systems. The guidance from NREL will focus on how to maximize efficiencies, pinpointing optimal mobility choices from analysis and deep research expertise.

Another NREL project under the lab's Sustainable Mobility umbrella is Connected Traveler, part of the ARPA-e TRANSNET initiative. Similar to RoadX, the Connected Traveler project will use a mix of behavior theory, vehicle connectivity, transportation modeling, and mobile technology to boost the energy efficiency of personal trips as well as the overall transportation system. By seeking to maximize the accuracy of predicted traveler behavior in response to real-time feedback and customized incentives, the system will promote energy-efficient travel choices to individuals.

NREL is also leading the Energy Department's Integrated Network Testbed for Energy Grid Research and Technology Experimentation (INTEGRATE), a multi-lab effort that connects vehicles with the utilities infrastructure and the built environment to increase the capacity, efficiency, and stability of the electric grid. Research focused on bi-directional charging, wireless electric vehicle charging, vehicle-to-grid power flow and controls, and second use of electric vehicle batteries for utility energy storage will have direct application to the lab's Sustainable Mobility Initiative efforts. In addition, NREL's Human Centered Energy Services research is exploring how wireless communications and advanced controls can positively affect people's quality of life while reducing their energy requirements, for anything from building climate control to mobility choices.

Urban Testbeds and Transportation as a Service

The escalating pressures of a modern transportation system will most effectively be put to test in urban settings—from parking shortages to rising populations and concentrated air pollution. In many ways, cities offer the best real-world case studies for sustainable mobility solutions.

Stan Young, NREL's urban mobility project leader, says there are "problems across the spectrum with our current road system." Young says that he believes that the traditional pattern of building more highways to meet vehicle demand is no longer sustainable. "Many of these problems come to head once you closely examine urban areas."

For example, in cities like Los Angeles, parking accounts for 30% of traffic congestion. With increased automation, new vehicles may soon be equipped with the capability to locate the closest available spot and self-park—saving time for the driver and reducing traffic congestion, while also decreasing energy consumption and emissions.

"Once you automate a vehicle, your toolbox for making mobility more efficient expands by a couple orders of magnitude," says Young.

Young is providing the lab with niche expertise and support for RoadX, the Connected Traveler, and the Sustainable Mobility Initiative, focusing on the expansion of NREL's capabilities for connected and intelligent transportation systems. In addition to the massive benefits of automation, Young sees connectivity between drivers, vehicles, and passengers as a technology that's already having profound impact on energy-efficient transportation. This momentum is building, he says, as ride-sharing business models transform the way many travelers are beginning to view ownership of a vehicle.

Transportation as a service, rather, is a concept that may flourish in urban settings as more vehicles and drivers are available on demand for an affordable price. Instead of choosing a vehicle that serves long-term needs, access to these services are shaping travelers' choices by satisfying their short-term, immediate needs.

As with most evolving technologies, establishing a true sustainable mobility system will take time, NREL says. Many questions remain about automated vehicle technology—including questions about what to expect from local and federal legislation, cybersecurity, and what the intersection of self-driving vehicles and the ride-sharing economy will look like. Because the state transportation departments oversee day-to-day systems operation, they will be the groups guiding how new technologies integrate with the larger transportation system, establishing any necessary rules and regulations, which will inform future research under NREL's Sustainable Mobility Initiative.

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