Project Description

Diesel engines, with a unique combination of efficiency, power, reliability, and durability, play a vital role in key economic sectors such as goods movement and public transportation. Known as one of the most widespread air pollution risks, however, diesel emissions have contributed to serious air pollution problems and public health impacts. Fine particles from diesels shorten the lives of nearly 21,000 people each year in the U.S., including almost 3,000 early deaths from lung cancer. New York State and the New York Metropolitan Area, heavily populated with concentrated urban areas and significant diesel fleets, have both been ranked highest in the nation in terms of health impacts from diesel emissions. A five-year study by researchers at New York University shows that emissions spewing from diesel trucks contribute significantly to the alarmingly high rates of asthma among school-aged children in South Bronx ( http://www.nyu.edu/public.affairs/releases/detail/1263).

To address the immediate health concerns related to emissions from existing diesel engines with funding constraints, cost-effective cleaning technologies and well-designed diesel retrofit strategies are crucial. Attention and effort so far have focused on retrofit product development/certification, but little has been done to optimize diesel retrofit strategies/programs, which implement retrofit deployment and play a critical role in achieving cost-effective diesel clean-up. There are many established and emerging retrofit technologies available to help upgrade the existing diesel engines and reduce emissions. Each alternative has its own strengths, weakness and variability/uncertainty in emission reduction efficiency. The emissions of diesel retrofit are also subject to many uncertain external factors, including environmental factors (e.g., temperature, humidity), fleet characteristics (e.g., age distribution of fleet, distribution of VMT by vehicle class, number and types of diesel engines), activity measures (e.g., speed distributions, distribution of VMT by roadway type), and fuel characteristics. Even with good certified retrofit technologies, unwise decisions in operations and deployment of a retrofit program could significantly limit the benefit. Retrofit devices need to be used in the right application. Good diesel clean-up strategies should be designed and implemented to take all these factors into account, identify the right technology and apply it to the right engine in the right area at the right time. There is little previous work on optimization models for fleet owners and diesel retrofit program managers to assist them in making informed decisions on their diesel fleet and retrofit programs.

This research proposes to integrate existing diesel retrofit emissions estimation models and optimization methods to address these questions by developing a suite of optimization models to support systematic diesel retrofit analysis, and by illustrating applications of the models in case studies. The models, with new contributions to academic literature, will take into account all the relevant information (i.e., costs and benefits, budget, and objectives) to help local and state retrofit managers understand how the many relevant factors interact to affect the appeal of different retrofit strategies. Equity is an important issue in transportation/environmental planning and will also be addressed in this study. The project will combine the investigator’s experiences with emissions assessment and optimization.