Incorporating Resilience into Transportation Infrastructure Planning

With the increasing rate of global change, resilience has gained attention as a concept to address the sustained functioning of systems subject to uncertain stressors. In particular, policy makers are beginning to place an... [ view full abstract ]

With the increasing rate of global change, resilience has gained attention as a concept to address the sustained functioning of systems subject to uncertain stressors. In particular, policy makers are beginning to place an emphasis on the importance of considering resilience and sustainability for policy and investment decisions. The concept of resilience underscores the need for a holistic, systems approach to assessing the interdependencies of social, economic, and environmental systems. Public policy and investment decisions for transportation infrastructure must be made in the context of uncertain future conditions and heterogeneity across spatial and temporal scales. 

To aid decision making for developing transportation infrastructure, the National Renewable Energy Laboratory has developed the Scenario Evaluation, Regionalization and Analysis (SERA) model. The SERA model is a geospatially and temporally oriented model that has been applied to determine optimal production and delivery scenarios for hydrogen, given resource availability and technology cost and performance, for use in fuel cell vehicles. In addition, the SERA model has been applied to plug-in electric vehicles. Augmenting SERA model capabilities with life cycle assessment data enables decision makers at local and regional levels to better understand potential impacts on the environment and human health.

Scenarios of possible futures are constructed to test the sensitivity of results. For example, scenarios can represent various future population densities, technological improvements, and changes in electricity generation. Existing model projections for improvements in vehicle efficiency, performance, and cost, and the resulting impact on vehicle sales, are leveraged to inform scenario development. Results reveal which hydrogen supply chain configurations offer the greatest benefits in terms of reducing greenhouse gas emissions, petroleum and other fossil fuel consumption, water consumption, criteria emissions, and life cycle costs by region. When electric vehicles are included in the modeling, the results project the relative market share of conventional vehicles, electric vehicles, and fuel cell vehicles along with the corresponding economic, social, and environmental benefits.

Preliminary results reveal that fuel cell vehicles based on gaseous hydrogen produced from natural gas require less water consumption than those based on hydrogen from woody biomass or wind electrolysis, conventional gasoline vehicles, or electric vehicles based on the U.S. average grid mix. However, based on geographic region and corresponding electricity mix, the well-to-pump water consumption for hydrogen can increase up to 300 percent. These results emphasize the importance of developing large-scale systems models that can account for geospatial differences in electricity mix. 

These assessment methods can inform infrastructure planning and investment decisions. The framework provides a systems-level lifecycle analysis capacity to assess infrastructure development, evaluate technologies and pathways, and guide research and development. By including sustainability indicators in the framework, the analytical methods also serve to incorporate resilience into transportation infrastructure planning. Specifically, indicators are selected to address the economic (e.g., direct user cost and total investment), social (e.g., employment, personal mobility, and public health impacts), environmental (e.g., GHG emissions and energy consumption) aspects of sustainability in attempt to holistically understand the impacts of planning and investment decisions.