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Truck platooning enabled by connected automated vehicle (CAV) technology has been demonstrated to effectively reduce fuel consumption for trucks in a platoon. However, given the limited number of trucks in the traffic stream, it remains questionable how great an energy saving it may yield for a practical freight system if we only rely on ad-hoc platooning. Assuming the presence of a central platooning coordinator, this paper is offered to substantiate truck platooning benefits in fuel economy produced by exploiting platooning opportunities arising from the United States’ domestic truck demands on its highway freight network. An integer programming model is utilized to schedule trucks’ itineraries to facilitate the formation of platoons at platoonable locations to maximize energy savings. A simplification of the real freight network and an approximation algorithm are used to solve the model efficiently. By analyzing the numerical results obtained, this study quantifies the importance of scheduled platooning in improving trucks’ fuel economy. Furthermore, the allowable platoon size, schedule flexibility, and fuel efficiency all play a crucial role in energy savings. Specifically, by assuming that following vehicles in a platoon obtain a 10% energy reduction, an average energy reduction of 8.48% per truck can be achieved for the overall network if the maximum platoon size is seven, and the schedule flexibility is 30 min. The cost–benefit analysis provided at the end suggests that the energy-saving benefits can offset the investment cost in truck platooning technology.
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Evaluating Cost Savings from Truck Caravanning
Truck platooning and related autonomous vehicle coordination concepts have been proposed as sustainable ways to increase profits and improve service quality. Recently the concept of truck caravanning, a hybrid truck platooning with only one truck driver required per platoon, has been proposed in the literature. This paper describes the research effort in developing a model that can estimate the cost savings of truck caravanning. The motivation of the proposed model is to investigate if substantial monetary savings exist to justify the initial capital investment (both in equipment and infrastructure) required for the implementation of the truck caravanning concept. A linear programming model is developed and used to evaluate different size networks. Results from numerical experiments indicate that a caravan size of four trucks or greater is needed for significant cost savings to be achieved and that driver compensation is the most critical factor dictating profitability.
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- Award ID(s):
- 2209829
- PAR ID:
- 10483469
- Publisher / Repository:
- Sage Journals
- Date Published:
- Journal Name:
- Transportation Research Record: Journal of the Transportation Research Board
- Volume:
- 2677
- Issue:
- 2
- ISSN:
- 0361-1981
- Page Range / eLocation ID:
- 78 to 97
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1177/03611981221101890
