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Abstract This article proposes a calculation methodology that starts from the demand calculation to supply a fleet bus with renewable hydrogen based on the electrolysis process until the energetic, economic, and environmental analyses, involving all the processes of the productive chair. Also considering the dynamic behaviour of the following hydrogen processes: production, storage, and use. The simplified scheme of the proposed system configuration to be studied consists of the use of alternative and renewable sources of energy (solar-wind-biogas) to generate electrical energy in order to produce hydrogen from electrolysis of the water, which is stored in its gaseous state and subsequently redirected to a filling station to be used as vehicle fuel in buses. The results show that to feed one bus the hybrid system generates an average of 78,110 kWh/month with an installed capacity of 1101.905 kW, producing 1209.90 kgH2/month through the electrolysis process from water. The results also show a range of electricity generation costs between 1.130 and 0.123 US$/kWh and H2 production between 0.963 and 0.110 US$/kWh. Concluding that the application of renewable energies to produce hydrogen and electricity for the public transport sector is an attractive alternative in the future throughout the country, because the proposed system is technically, economically and ecologically viable.

Abstract The decentralised infrastructure of the Danish thermal and electricity infrastructure has improved security, efficiency and reliability in energy transmission and consumption in each of the systems. To further improve this trend, this paper investigates the concept of decentralised coupling of electrified thermal and transportation system in low voltage residential network to identify their operational flexibility. In this paper, diagnosis based on actual data from the energy distributors and surveys is used to understand and improve the flexibility of an integrated energy system. The main contribution is a set up model with an autonomous control system that can assess the potential flexibility from thermal units (eg heat pumps and storages) and electric vehicles (EV) charging systems, in the low voltage distribution network as a multi-energy system. Each thermal system and EV charging has its respective individual controller. The proposed control technique manages to successfully operate and control the thermal units and EVs charging system within the recommended operating limits of grid voltage, and by sharing flexibility within the specific network integrated with multi-carrier energy systems. It has the capability of sensing local key control parameters like node voltage, state of charge of EV, temperature and level of hot water in the storage tank. These control parameters allow scheduling, re-scheduling, and decision making on the operation of individual thermal and EV charging-unit with operational priorities. This enhances the sharing of flexibility for proper coordination, control, and management of thermal and EV charging systems in low voltage (LV) distribution networks with mutual technical benefits. From the results of the steady-state analysis of power system, the application of the proposed control architecture is found to be effective to manage grid congestions and local voltage control, satisfying the thermal energy requirements of the customer as well as charging needs of EV.

AbstractThis paper presents the results of a study carried out to examine the feasibility of integrating electric drive vehicles (EDVs) in the Danish electricity network which is characterised by high wind power penetration. One of the main aims of this study was to examine the effect of EDVs on the Danish electricity network, wind power penetration and electricity market. In particular the study examined the effect of EDVs on the generation capacity constraints, load curve, cross border transmission capacity and the type of generating sources (renewable/conventional) which are likely to fuel these cars. The study was carried out considering the Danish electricity network state around 2025, when the EDV penetration levels would be significant enough to have an impact on the power system. Some of the interesting findings of this study are—EDVs have the potential to assist in integrating more wind power (by adding more market value to wind power and by improving over all power system reliability) and integration of EDV does not require major additional infrastructure (generation/transmission cross border capacities). Copyright © 2009 John Wiley & Sons, Ltd.

This paper explores the possibilities for increasing energy efficiency of ship propulsion systems by the use and appropriate control of adjustable speed drives based on pulse width modulation voltage source inverters (PWM VSIs) and induction motors (IMs). A passenger ship moved by two twin propulsion units using IMs with a rated power of 7,000 kW is chosen as case study. Each IM is supplied by an AC-AC power converter in a back-to-back configuration, based on three-level neutral point clamped (NPC) VSIs. To increase the overall efficiency of the propulsion drive, the IM side control is integrated with a suitable electrical loss minimization technique (ELMT). A complete dynamic model of the IM propulsion drive is developed, including the IM model taking into account the iron loss, the power converter model with PWM, and the control system with the ELMT. Results show the capability of the ELMT to significantly increase the overall efficiency of the IM by about 10% at full load.

Concerns about the environment have grown worldwide as carbon emissions, one of the primary drivers of global warming, continue to rise. As the transportation industry is one of the most greenhouse-gas-emitting sectors in the European Union (EU), the need for environmentally friendly solutions has been increasing progressively. In this regard, electric vehicles (EVs) play an important part in mitigating some of the adverse effects of road transportation on human health, the environment, and climate. Therefore, the popularity of electric vehicles in the EU has recently increased significantly because of climate change mitigation efforts. In this paper, we aim to analyze and compare the performance of European EVs with multi-criteria decision-making (MCDM) methods, namely preference selection index (PSI) and axial-distance-based aggregated measurement (ADAM) techniques, which do not need the criteria weights for measurement and a novel three-dimensional evaluation technique. The results of both MCDM methods reveal that the EVs of the Tesla Inc. and Geely Group models are found to be the best-performing vehicles. We also investigate the efficiency of the European EV market by the super-efficiency data envelopment analysis (DEA) technique, which enables us to evaluate among efficient units. The efficiency scores indicate that five EVs from three different manufacturer groups obtain efficiency levels. To the best of our knowledge, European EV market evaluation by integrated and comparative analysis has not been encountered for the EU on a group basis. The suggested MCDM and DEA techniques can benefit stakeholders while assessing the European EV market.

Recent unveiling of electric semi-trucks by a number of electric vehicle manufacturers indicates that part of the existing long-distance transportation fleets may soon be electrified. Operators of electric fleets will have to select travel routes considering charging station availability and cost of charging in addition to usual factors such as congestion and travel time. This requires combined modeling of transportation and electric power networks. We present such a model that considers interactions between the two networks to develop optimal routing strategies. The problem is formulated as a multi-objective bilevel conic optimization model. The upper level obtains the routing decision by minimizing a function of charging cost and travel time. The routing decision is used in the lower level that solves the AC optimal power flow model, using second order cone constraints, to determine nodal electricity prices. The model is demonstrated using a numerical problem with 24-Node transport network supported by a modified 5-Bus PJM network. The results show that our model yields optimal routes and charging strategies to meet the objectives of fleet operators. Results also indicate that the optimal routing and charging strategies of the electrified transportation fleet can support power networks to reduce nodal prices via demand response

Cycling-based mobility services or 'Cycling as a Service' (CaaS) have recently expanded in number and scale in the Netherlands. In contrast to the contexts of most other CaaS studies to date, cycling has a high modal share and strong institutions in the Dutch context. However, these supportive features have not translated into straightforward success for CaaS providers. Instead, responses to CaaS providers have varied widely, from tolerance to opposition. In this study we employ a combined business model and transition perspective to investigate this variation and its implications for CaaS in Dutch urban mobility systems. We present value propositions derived from business models, and integrate these into Hoogma's fit-and-stretch strategy framework for emerging niches. This enables a comparison between technology design and value propositions, and an analysis of the CaaS niche's transitions potential. Our findings clarify the strategies used by niche actors to enter and operate within established cycling regimes.

The northern Outer Banks coastal area in North Carolina is well suited to drawing bicycle tourism because of its geography, climate, and attractions. In 2003, the North Carolina Department of Transportation commissioned a study to examine the value of public investment in bicycle facilities that have been constructed in this area over the past 10 years at a cost of approximately $6.7 million. A particular challenge in conducting this study was that tourists visited the Outer Banks for a variety of reasons, not just for cycling. Thus, the collection of information on the amount and nature of bicycling activity and on the spending patterns of bicyclists in the area was critical for the development of an economic impact analysis. Researchers surveyed cyclists using the bicycle facilities (shared-use paths and wide paved shoulders) and obtained data from self-administered surveys of tourists at visitor centers during the primary tourist season. The data collected were then used to determine the economic impact of bicycling visitors to the area. Seventeen percent of tourists to the area reported that they bicycled while there; this translates to 680,000 people annually. The economic impact of bicycling visitors is significant: a conservative annual estimate is $60 million, with 1,407 jobs created or supported per year. This is almost nine times greater than the one-time expenditure required to construct the facilities. Continued investment in bicycle facilities is expected to increase this favorable economic impact and is therefore recommended.

Abstract The marine transportation sector, responsible for consuming a large amount of degraded fuel oil, is one of the major contributors to global warming and air pollution. These effects are responsible for a large number of premature deaths in the US and throughout the world. The international regulation known as the 2008 MARPOL Annex VI Amendment, which is enforced by the International Maritime Organization (IMO), has imposed progressively more stringent limits on emissions from marine vessels. Biodiesel, an environmentally friendly, renewable, clean, and low-carbon fuel, is regarded as the most appropriate alternative fuel for marine vessels. However, the promotion of biodiesel use in water-borne transportation is considered to be a bigger challenge than its more successful development in land-based applications. The major obstacles to promoting biodiesel blends in marine transportation are examined in this study. The strategies proposed to overcome these obstacles include the comprehensive field testing of the biodiesel blends in marine vessels of various representative types, establishing a marine-grade biodiesel specification, increasing the price competitiveness of marine-grade biodiesel by reducing its manufacturing costs, providing tax cuts, exemptions, and government subsidies, increasing the amount of biodiesel use in marine applications, adopting compatible elastomers and metallic materials in fuel feeding systems and storage tanks, applying approaches or technologies suitable for improving the low-temperature fluidity of biodiesel blends, and increasing the added value of purified glycerol. The effective application of these strategies will enable the more widespread use of biodiesel in marine applications, significantly reducing emissions from ships, improving global air quality, protecting the ecological environment and improving people’s health.