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Abstract: As electric vehicle (EV) batteries degrade to 80 % of their full capacity, they become unsuitable for electric vehicle propulsion but remain viable for energy storage applications in solar and wind power plants. This study aims to estimate the energy storage potential of used-EV batteries for stationary applications in the Indian context. To estimate the renewable energy generation and used-EV capacity, the study adopted International Energy Agency (IEA) and International Council on Clean Transportation (ICCT) growth scenarios for renewable energy growth and electric vehicle growth, respectively. Battery degradation models for popular battery chemistries in electric vehicle mobility, namely Lithium Iron Phosphate, Lithium Manganese Oxide, and Nickel Manganese Cobalt, are employed to estimate reusable battery capacity. The first life for these battery chemistries, for mobility applications, ranges from 3.5 to 7 years. Results indicate an estimated storage potential of 1300–1870 GWh in used electric vehicle batteries in India by 2038. This is equivalent to 17 % – 39 % of average daily energy generation from solar and wind power plants in various scenarios by the year 2038. This research contributes to SDG-7 by facilitating clean energy accessibility through renewable energy storage and supports emission reduction efforts in transportation and energy sectors, thereby fostering sustainable cities (SDG-11).
Keywords: used-EV batteries, battery degradation, renewable energy, energy storage, battery capacity, Li-ion batteries
Published in DKUM: 09.08.2024; Views: 102; Downloads: 7
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Abstract: The paper presents the results of research aimed at evaluating the possibility of using selected biomass wastes to produce solid biofuels. In this work, the thermochemical properties of two lignocellulosic biomasses, namely, miscantshus (Miscanthus × Giganteus) and hops (Humulus lupulus), and non-lignocellulosic biomass, namely, municipal solid waste, and their mixtures (micanthus + municipal solid waste and hops + municipal solid waste) were studied using the torrefaction process as the main method for investigation. The effects of various torrefaction temperatures (250, 300, and 350 °C) and times (30 and 60 min) were evaluated. Proximate and ultimate analyses were performed on the torrefied samples. The following can be stated: as the torrefaction temperature and time increased, mass and energy yields decreased while the higher heating values (HHVs) and fuel ratios (FRs) increased, together with carbon contents (C). In addition, energy on return investment (EROI) was studied; the maximum EROI of 28 was achieved for MSW biochar at 250 °C for 30 min. The results of studying greenhouse gas emissions (GHGs) showed a reduction of around 88% when using torrefied biochar as a substitute for coal. In sum, this study shows that torrefaction pre-treatment can improve the physicochemical properties of raw biomasses to a level comparable with coal, and could be helpful in better understanding the conversion of those biomasses into a valuable, solid biofuel.
Keywords: torrefaction, waste biomass, renewable energy, fuel ratio, greenhouse gas emission, GHG
Published in DKUM: 29.03.2024; Views: 221; Downloads: 14
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Abstract: By integrating renewable energy sources into the existing distribution network, the characteristics and local stability of the network is highly impacted. The network, which was built with the goal of a directed energy flow from large conventional sources connected to the transmission network via the distribution network to consumers, can change the direction of the energy flow. The adoption of environmental commitments and directives encourages the integration of local dispersed energy sources, which can worsen voltage conditions in the distribution network. To avoid excessive local production, distribution network operators must limit the installation of new generati on units, as it is necessary to take into account the quality of power supply by monitoring its network parameters, such as the appropriate voltage profi le and the rati o between acti ve and reacti ve power. On the other hand, excessive loads due to the mass transiti on of household heati ng and transport towards electricity can also pose a problem for high-quality electricity supply due to the excessive voltage drop. The arti cle presents an algorithm for determining the maximum size of unit producti on and the maximum load at a node in the distributi on network. Also demonstrated is the use of variable tap transformer technology, which adjusts the tap of the transformer to provide an appropriate voltage profi le in the network. The enti re analysis was performed on a model of a real medium-voltage network, in which solar and hydropower plants are already included. The model was verifi ed by comparing its calculated values with actual measurements. The goal was to determine the size of the unit’s maximum producti on, as well as the size of the maximum load, by using the diff erenti al evoluti on algorithm, while keeping voltage profi les within the permissible limits. The results of the analysis are presented in the article.
Keywords: distribution network, renewable energy sources, optimisation method, voltage profile
Published in DKUM: 30.10.2023; Views: 420; Downloads: 14
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Abstract: This research paper conducts the process of selecting the criteria that are the most appropriate for a transition from conventional to sustainable warehousing. SWOT analysis is used to emphasise the weaknesses of conventional and the strengths of sustainable warehousing to select the most appropriate for the herein presented study. The results have been verified via a questionnaire filled out by professionals in economics, logistics and warehousing, and mechanical engineering. be added under the methodology section. The results gave the five most important criteria by transforming the conventional into sustainable warehousing. Finally, the paper concluded that renewable energy sources are the most important criteria for transforming by conventional to sustainable warehousing by environmental aspects, as well as the smart technology is above all other criteria by economic aspect. Moreover, providing personal protection equipment and servicing machinery and vehicle on regular basis are the two mainly criteria by social (safety) aspect.
Keywords: logistics, sustainable warehousing, SWOT analysis, renewable energy
Published in DKUM: 13.07.2023; Views: 337; Downloads: 33
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Abstract: The diploma thesis consists of design and numerical simulation of the wind turbine. Geometries are designed according to two theories, the Betz theory and the Schmitz theory. I used Solidworks for 3D modeling of the both rotors. Using Ansys software package, we performed numerical simulations of a rigid body for two different wind speed regimes. We were interested in the angular velocity of the spinning blades, which in combination with moment give us power.
Keywords: Renewable energy, wind energy, numerical simulation, wind turbine, blade design, Betz and Schmitz theory
Published in DKUM: 09.08.2018; Views: 1678; Downloads: 189
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