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Tiago L. Farias – One of the best experts on this subject based on the ideXlab platform.
Environmental and financial impacts of adopting Alternative Vehicle technologies and relocation strategies in station-based one-way carsharing: An application in the city of Lisbon, PortugalTransportation Research Part D: Transport and Environment, 2017Co-Authors: Ana S. Vasconcelos, Luis Miguel Martínez, Gonçalo Homem De Almeida Correia, Daniel C. Guimarães, Tiago L. FariasAbstract:
Abstract In this study we propose a cost-benefit analysis method to assess the performance of carsharing systems with conventional and Alternative Vehicles, taking into account the different stakeholders’ financial costs as well as the environmental benefits. The method was applied to simulated mobility data for the case study of Lisbon, Portugal. Regarding operators’ annual profit, only diesel Vehicles promised a profit of 544 thousand euros per year without Vehicle relocations, and 646 thousand with relocations. Electric Vehicles would lead to estimated losses of 1.1 million euros per year without Vehicle relocations, which could go down to 890 thousand euros of financial losses with relocations. Fleets using two-seater gasoline Vehicles can also achieve positive profit if they implement relocations. When analyzing the performance of carsharing systems with no relocations, only electric Vehicles showed positive environmental impacts. However, when Vehicles are relocated, the environmental benefit decreases because of the added kilometers. Additional scenarios for carsharing with electric Vehicles were performed: free parking charges; duty-free costs; and depreciation costs similar to those of diesel Vehicles. All the analyses showed positive annual net profits for the operator, indicating that policies might promote the use of cleaner Vehicles. From the travellers’ perspective, the overall balance is always negative because the price paid for the carsharing system is not offset by the savings of not using a private car or public transport. This happened even if we add the more subjective benefit of the added utility of an extra transport option to the current mode choice.
Electric Vehicle parking in European and American context: Economic, energy and environmental analysisTransportation Research Part A: Policy and Practice, 2014Co-Authors: Marta V. Faria, Patrícia Baptista, Tiago L. FariasAbstract:
The transportation sector faces increasing challenges related to energy consumption and local and global emissions profiles. Thus, Alternative Vehicle technologies and energy pathways are being considered in order to overturn this trend and electric mobility is considered one adequate possibility towards a more sustainable transportation sector.
Impact of Alternative Vehicle Technologies on Measured Vehicle EmissionsTransportation Land Use Planning and Air Quality, 2008Co-Authors: Haibo Zhai, H C Frey, Nagui M. Rouphail, Gonçalo Gonçalves, Tiago L. FariasAbstract:
Emerging Vehicle technologies such as hybrids, flex-fuel, electric, and fuel cells are projected to exceed 25% of total light-duty Vehicle sales by 2030. Because of their higher energy efficiency, hybrid electric Vehicles (HEVs) produce lower emissions of greenhouse gases such as CO 2 than comparable gasoline Vehicles. Measurements of selected advanced gasoline and diesel direct injection Vehicles and gasoline-electric hybrid Vehicles indicate that the HEV had the lowest emissions and highest fuel economy. One study concluded that replacing all conventional Vehicles with HEV’s could cut total CO and NO x emissions in half. Flex-fuel Vehicles that can use either gasoline or ethanol 85 (E85), a blend of 85% ethanol and 15% gasoline by volume have sensors that can analyze the fuel-air mixture and adjust the fuel injection and timing. Since ethanol is an oxygenated fuel, the use of ethanol may reduce emissions of products of incomplete combustion including CO and HC. However, the oxygenate may tend to increase NO x emissions because of lean combustion. The use of blends with a high percentage of ethanol in the mix was found to produce increased emissions of NO x and aldehydes as the ethanol content increased. However, measurements of flex-fuel Chevrolet Lumina Vehicles indicated that the use of E85 may decrease Vehicle CO, HC and NO x emissions, but increase aldehydes emissions when compared to gasoline Vehicles showed that NO x emissions increased with increasing ethanol content for some fuels, but were unaffected by ethanol content for other fuels, depending on fuel volatility. Hochhauser found that use of ethanol fuel may increase Vehicle permeation emissions of VOC. Therefore, flex-fuel Vehicles do not assure lower emissions for at least some pollutants compared to dedicated gasoline Vehicles. The objective of this study is to develop an advanced modeling system to quantify influences of land use and Vehicle technologies on on-road Vehicle emissions such as CO 2 , CO, and NO x . The main focus here is to demonstrate a methodology for assessing how differences in driving cycles affect link-based average emission rates for selected Vehicle technologies. The methodology requires second-by-second data, with a preference for real-world in-use data where possible. The methodology is illustrated here based on data from one flex-fuel Vehicle that was measured during actual driving using a portable emission measurement system (PEMS) on both gasoline and E85 and for one HEV that was tested on a chassis dynamometer. Testing for the flex-fueled Vehicle was conducted by Instituto Superior Tecnico (IST) in Lisbon, Portugal. The flex-fuel Vehicle is a European 2006 flex-fuel Ford Focus wagon with a 1.8 liter engine (92 kW/6000rpm, 165 Nm/4000rpm). By comparison, the U.S. version of the Focus has a 2.0 liter engine (97 kW/6000rpm, 175 Nm/4000rpm). The HEV is a 2001 Toyota Prius with a 1.5 liter gasoline engine.
Jens A. Stephan – One of the best experts on this subject based on the ideXlab platform.
Trading volume in options and common stock around quarterly earnings announcementsReview of Quantitative Finance and Accounting, 1993Co-Authors: Donna R. Philbrick, Jens A. StephanAbstract:
This study examines trading in call and put options around quarterly earnings announcements and investigates whether the existence of these options affects the common stock trading volume response to these announcements. We find that the options trading volume reaction to earnings announcements is larger than the corresponding reaction in common stock. Consistent with the idea that options provide an Alternative Vehicle for trading on information, the existence of these options lowers the level of trading in common stock. Options also appear to offer investors an Alternative method of taking short positions, as shown by the symmetric stock market trading volume reaction to good versus bad news for firms with listed options. In contrast, firms without listed options exhibit a larger trading volume response to good news than to bad news of similar magnitude.
Kenneth Gillingham – One of the best experts on this subject based on the ideXlab platform.
Economic impact of the integration of Alternative Vehicle technologies into the New Zealand Vehicle fleetJournal of Cleaner Production, 2010Co-Authors: Jonathan Leaver, Kenneth GillinghamAbstract:
Abstract A multi-regional integrated energy systems model is developed to assess the economic impact of hydrogen fuel cell, hydrogen internal combustion, and battery electric technologies on the economy of New Zealand. Base case results suggest that a hydrogen fuel dominant Vehicle fleet offers economic savings over a conventional fleet but requires the largest sequestration capacity as 75% of hydrogen fuel production is derived from fossil fuel. When the oil price is varied from US$120 to US$240 per barrel in 2030, and the carbon tax varied from US$30 to US$90 per tonne of CO2 equivalent, the change in savings ranges from −65% to +25%.
assessment of primary impacts of a hydrogen economy in new zealand using unisydInternational Journal of Hydrogen Energy, 2009Co-Authors: Jonathan Leaver, Kenneth Gillingham, Luke H T LeaverAbstract:
Small economies such as New Zealand risk significant economic hardship without careful evaluation of Alternatives to petroleum-based transportation due to the adverse effects of climate change and depleting international oil reserves. This paper uses an integrated multi-regional multi-fleet system dynamics model of New Zealand’s energy economy to assess the primary impacts of Alternative Vehicle fleet technologies. Results suggest that hydrogen fuelled HICEs and FCVs may offer significantly greater economic savings than BEVs due to a much lower capital cost. Under our Base Case, 65% of the light fleet are HICEs and FCVs and 5% BEVs. Excluding hydrogen Vehicles from the Vehicle fleet can result in an average annual cost of US$562 per Vehicle between 2015 and 2050. Co-production of hydrogen and electricity using coal gasification with carbon capture and storage is the dominant long term hydrogen production technology.