Analytical Modeling Framework to Assess the Economic and Environmental Impacts of Residential Deliveries, and Evaluate Sustainable Last-Mile Strategies

In the last decade, e‐commerce has grown substantially, increasing business‐to‐business, business‐to‐consumer, and consumer‐to‐consumer transactions. While this has brought prosperity for the e-retailers, the ever-increasing consumer demand has brought more trucks to the residential areas, bringing along externalities such as congestion, air and noise pollution, and energy consumption. To cope with this, different logistics strategies such as the introduction of micro-hubs, alternative delivery points, and use of cargo bikes and zero emission vehicles for the last mile have been introduced and, in some cases, implemented as well. This project, hence, aims to develop an analytical framework to model urban last mile delivery. In particular, this study will build upon the previously developed econometric behavior models that capture e-commerce demand. Then, based on continuous approximation techniques, the authors will model the last-mile delivery operations. And finally, using the cost-based sustainability assessment model (developed in this study), the authors will estimate the economic and environmental impacts of residential deliveries under different city logistics strategies.View the NCST Project Webpag

Automated Vehicles are Expected to Increase Driving and Emissions Without Policy Intervention

Researchers at UC Davis explored what an automated vehicle future in the San Francisco Bay Area might look like by simulating:1) A 100% personal automated vehicle future and its effects on travel and greenhouse emissions.2) The introduction of an automated taxi service with plausible per-mile fares and its effects on conventional personal vehicle and transit travel.The researchers used the Metropolitan Transportation Commission’s activity-based travel demand model (MTC-ABM) and MATSim, an agent-based transportation model, to carry out the simulations. This policy brief summarizes the results, which provide insight into the relative benefits of each service and automated vehicle technology and the potential market for these services.View the NCST Project Webpag

Coping with the Rise of E-commerce Generated Home Deliveries through Innovative Last-Mile Technologies and Strategies

Caltrans 65A0686 Task Order 066USDOT Grant 69A3551747114E-commerce can potentially make urban goods flow economically viable, environmentally efficient, and socially equitable. However, as e-retailers compete with increasingly consumer-focused services, urban freight witnesses a significant increase in associated distribution costs and negative externalities, particularly affecting those living close to logistics clusters. Hence, to remain competitive, e-retailers deploy alternate last-mile distribution strategies. These alternate strategies, such as those that include the use of electric delivery trucks for last-mile operations, a fleet of crowdsourced drivers for last-mile delivery, consolidation facilities coupled with light-duty delivery vehicles for a multi-echelon distribution, or collection-points for customer pickup, can restore sustainable urban goods flow. Thus, in this study, the authors investigate the opportunities and challenges associated with alternate last-mile distribution strategies for an e-retailer offering expedited service with rush delivery within strict timeframes. To this end, the authors formulate a last-mile network design (LMND) problem as a dynamic-stochastic two-echelon capacitated location routing problem with time-windows (DS-2E-C-LRP-TW) addressed with an adaptive large neighborhood search (ALNS) metaheuristic

Improving Environmental Justice and Mobility in Southeast Los Angeles

CCRP0017This case study is part of the Climate Smart Transportation and Communities Consortium (CSTACC), case studies that were conducted in various locations throughout the state to analyze environmental justice issues in low income, communities of color. This study took place in southeast Los Angeles County in partnership with the Southeast Los Angeles Collaborative (SELAC), a non-profit community-based umbrella organization representing 8 cities and several unincorporated areas. The case study has two parts. The first part examines impacts of heavy duty trucks and finds the main problems to be traffic safety and particulate emissions. An analysis of regional freight traffic reveals that current and planned regulations to achieve zero emission truck targets will significantly reduce truck-related emissions. A local analysis showed higher than average truck involved crashes and safety hot spots. Local traffic management strategies are recommended to increase safety. The second part examines public transit job accessibility. Transit accessibility depends on both service level and access to bus stops. Reductions in service that took place as a result of the pandemic greatly reduced job access. Recommendations include exploring bike share and car share options to reduce travel times to and from bus stops, and restoring service to pre-pandemic levels

Assessing Sustainability of E-Commerce Goods Distribution

The growth of e-commerce, spurred by the internet, has transformed urban goods flow. What would previously have been a trip to a store is now a hassle-free delivery to the home. With consolidated and optimized delivery tours, e-commerce has the potential to make urban goods flow economically viable, environmentally efficient, and socially equitable. However, as e-retailers compete with increasingly consumer-focused service, urban freight witnesses a significant increase in associated distribution costs and negative externalities including greenhouse gas emissions advancing global climate change, as well as criteria pollutant emissions worsening local air quality and thus affecting those living close to logistics clusters. Thus, considering the potential of e-commerce to render economically viable, environmentally efficient, and socially equitable urban goods flow, it is pertinent to understand the opportunities and challenges associated with urban freight in light of the increasingly consumer-focused e-commerce distribution. To this end, the author develops A) the impact of e-commerce on urban goods distribution, with a simulation framework founded on consumer shopping behavior simulating urban goods flow, B) the impact of key delivery environment parameters on e-commerce goods distribution, with a continuous approximation (CA) framework modeling last-mile distribution operation for an e-retailer, and C) the impact of demand uncertainty on e-commerce goods distribution, with a discrete optimization framework formulating a last-mile network design (LMND) problem as a dynamic-stochastic two-echelon capacitated location routing problem with time-windows (DS-2E-C-LRP-TW), addressed using an adaptive large neighborhood search (ALNS) metaheuristic algorithm

Assessing last-mile distribution resilience under demand disruptions.

The COVID-19 pandemic led to a significant breakdown of the traditional retail sector resulting in an unprecedented surge in e-commerce demand for the delivery of essential goods. Consequently, the pandemic raised concerns pertaining to e-retailers' ability to maintain and efficiently restore level of service in the event of such low-probability high-severity market disruptions. Thus, considering e-retailers' role in the supply of essential goods, this study assesses the resilience of last-mile distribution operations under disruptions by integrating a Continuous Approximation (CA) based last-mile distribution model, the resilience triangle concept, and the Robustness, Redundancy, Resourcefulness, and Rapidity (R4) resilience framework. The proposed R4 Last Mile Distribution Resilience Triangle Framework is a novel performance-based qualitative-cum-quantitative domain-agnostic framework. Through a set of empirical analyses, this study highlights the opportunities and challenges of different distribution/outsourcing strategies to cope with disruption. In particular, the authors analyzed the use of an independent crowdsourced fleet (flexible service contingent on driver availability); the use of collection-point pickup (unconstrained downstream capacity contingent on customer willingness to self-collect); and integration with a logistics service provider (reliable service with high distribution costs). Overall, this work recommends the e-retailers to create a suitable platform to ensure reliable crowdsourced deliveries, position sufficient collection-points to ensure customer willingness to self-collect, and negotiate contracts with several logistics service providers to ensure adequate backup distribution

The Sustainability of Alternative Last-Mile Delivery Strategies

In the last decade, e-commerce has grown substantially and transformed individual shopping behaviors. Most shopping activities—at least part of the search, if not the purchase itself—now involve an online component. This has consequently changed commodity flow and urban goods distribution. E-commerce has the potential to reduce the negative impacts of shopping on the environment by substituting individual shopping trips to stores using personal cars with optimized truck deliveries. However, shopping behavior is often more complex than this one-to-one substitution.Additionally, e-retailers entice consumers with free shipping, free returns, same-day, one-hour or two-hour expedited deliveries, and more in a quest for increased market share. These enhanced services result in additional distances driven, emissions, and operational costs for the e-retailer. The increasing customer expectations around lead time, delivery time, and return policy present a need for more sustainable delivery options, particularly for the “last mile” between the distribution center and the customer. Last-mile operators are considering alternatives to traditional diesel truck-based, door-to-door delivery such as use of alternative fuel (e.g., electric) vehicles, delivery from micro-hubs using cargo bikes, customer pickup at collection points, and crowdsourced deliveries. Researchers at the University of California, Davis developed models for e-commerce demand, last-mile delivery operations, and cost and sustainability assessment, then applied this modeling framework to a case study in Southern California to evaluate the potential impact of these strategies under different delivery scenarios. This policy brief summarizes findings from that research, along with policy implications.View the NCST Project Webpag