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The aim of this paper is to scrutinize smart biking in the context of gendered innovations and sustainable transport. Based on media representations, interviews, reports and surveys, the paper situates the establishment of the Chinese biking company Mobike in the landscapes of recent innovation strategies. What are the gendered implications of shared biking and Mobike design and technology? Does Mobike provide a challenge to the car-centric developments of urban mobility in China? What are the broader lessons to be learned in terms of sustainable urban transport? The Mobike company rolled out its first waves of bikes in the streets in Shanghai and Beijing in 2016, since when smart biking has spread like wildfire, particularly in China, but also in other countries around the globe. This paper contributes to situating and analyzing innovative practices related to gender and sustainability. Mobike was invented by a woman, Hu Weiwei, who set out to address the pressing needs of urban residents in respect of more convenient, sustainable and efficient modes of transport. It is argued that Mobike should be seen as an experimental case of disruptive gendered innovations that feeds into the challenges of sustainable urban transport and social equality.

Abstract This paper presents a study of the combined influence of battery models and sizing strategy for hybrid and battery-based electric vehicles. In particular, the aim is to find the number of battery (and supercapacitor) cells to propel a light vehicle to run two different standard driving cycles. Three equivalent circuit models are considered to simulate the battery electrical performance: linear static, non-linear static and non-linear with first-order dynamics. When dimensioning a battery-based vehicle, less complex models may lead to a solution with more battery cells and higher costs. Despite the same tendency, when a hybrid vehicle is taken into account, the influence of the battery models is dependent on the sizing strategy. In this work, two sizing strategies are evaluated: dynamic programming and filter-based. For the latter, the complexity of the battery model has a clear influence on the result of the sizing problem. On the other hand, a modest influence is observed when a dynamic programming strategy is followed.

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.

Tyre modelling is a major challenge when using time domain multibody simulation models to evaluate ride comfort on off-highway commercial vehicles. Further, parameters for these big tyres are difficult to obtain and thus, commercial car tyre models are difficult to apply. In this research work, a simple vertical tyre model for off-highway ride comfort evaluation is suggested. A displaced volume approach has been developed and combined with the slip theory to yield a tyre model that can be characterised by only three parameters. Full scale measurements on a dump truck have been carried out. Force responses from measurements are compared to the simulation results. Acceleration responses and the level of whole-body vibrations have also been compared.

The Danish EDISON project has been launched to investigate how a large fleet of electric vehicles (EVs) can be integrated in a way that supports the electric grid while benefitting both individual car owners, and society as a whole through reductions in CO2 emissions. The consortium partners include energy companies, technology suppliers and research laboratories and institutes. The aim is to perform a thorough investigation of the challenges and opportunities of EVs and then to deliver a technical platform that can be demonstrated on the Danish island of Bornholm. To reach this goal, a vast amount of research is done in various areas of EV technology by the project partners.

This paper proposes different smart charging algorithms for electric vehicles (EVs) to find out the maximum grid capability in dealing with these new devices. The main objective is to obtain maximum EV penetration in the distribution grid without reinforcing the grid in order to avoid any cost for distribution system operators (DSOs). Two smart charging algorithms are proposed in this study. The proposed algorithms are applied to a part of the Danish distribution grid as a case study. As a comparison, a dumb charging scenario, i.e. charging EVs without any specific order or algorithm, is also simulated. Simulation results demonstrate the capability of the smart charging methods to increase the penetration of EVs up to three times, compared to the base case.

Vehicle-to-Grid (V2G) systems are an emerging concept of utilizing the battery storage of electric vehicles (EVs) for providing power system regulation services. This technology could be used to balance the variable electricity generated from various renewable energy sources. This article considers a model of an aggregated electric vehicle based battery storage to support an isolated power system operating with a large wind power penetration in the Danish island of Bornholm. From the simulation results, the EV battery storages represented by the V2G systems are able to integrate more fluctuating wind power. The islanded Bornholm power system operates satisfactory for the case of replacing most of the conventional generator reserves with V2G systems, which may represent a future operation scenario.

AbstractSeveral Arctic marine mammal species are predicted to be negatively impacted by rapid sea ice loss associated with ongoing ocean warming. However, consequences for Arctic whales remain uncertain. To investigate how Arctic whales responded to past climatic fluctuations, we analysed 206 mitochondrial genomes from beluga whales (Delphinapterus leucas) sampled across their circumpolar range, and four nuclear genomes, covering both the Atlantic and the Pacific Arctic region. We found four well‐differentiated mitochondrial lineages, which were established before the onset of the last glacial expansion ~110 thousand years ago. Our findings suggested these lineages diverged in allopatry, reflecting isolation of populations during glacial periods when the Arctic sea‐shelf was covered by multiyear sea ice. Subsequent population expansion and secondary contact between the Atlantic and Pacific Oceans shaped the current geographic distribution of lineages, and may have facilitated mitochondrial introgression. Our demographic reconstructions based on both mitochondrial and nuclear genomes showed markedly lower population sizes during the Last Glacial Maximum (LGM) compared to the preceding Eemian and current Holocene interglacial periods. Habitat modelling similarly revealed less suitable habitat during the LGM (glacial) than at present (interglacial). Together, our findings suggested the association between climate, population size, and available habitat in belugas. Forecasts for year 2100 showed that beluga habitat will decrease and shift northwards as oceans continue to warm, putatively leading to population declines in some beluga populations. Finally, we identified vulnerable populations which, if extirpated as a consequence of ocean warming, will lead to a substantial decline of species‐wide haplotype diversity.