Assessing the economic and environmental benefits of transitioning to a zero- or near-zero emission bus fleet
The Rhode Island Public Transit Authority (RIPTA) is charged with meeting numerous interrelated federal, state, and local requirements for congestion mitigation, air quality improvement, and transit service reliability. Converting its fleet to zero or near-zero emission vehicles has the potential to help RIPTA meet these obligations while supporting various state and local sustainability commitments. However, significant operational, infrastructure and cost constraints exist and must be addressed for long-term success while balancing environmental goals with important co-priorities of affordable service, reliability, equity, and operational flexibility. The introduction of new technologies into the fleet should be done in a manner that minimizes impacts to riders and provides continuity of service while maximizing environmental benefits.
To fully assess the opportunities and implications of fleet conversion and develop a strategy that is sustainable over the long term, a technical assessment of commercially available technologies and their ability to meet RIPTA’s operational needs was conducted. Battery-electric, fuel cell, and natural gas buses were evaluated for commercial readiness, fuel availability, performance, and capital, maintenance, and infrastructure costs. These results informed eight fleet conversion scenarios to one or a combination of alternative technologies and were evaluated against a baseline diesel scenario for cost and emissions over a 30-year timeframe.
