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Abstract: An integrated top-down methodology for assessing and promoting progress towards a circular economy at macro (national) and micro (company) levels is presented. It is based on the MICRON (MIcroCirculaR ecOnomy iNdex) framework developed by Baratsas et al. (2022) for companies. In this paper, it has been extended to enable a consistent assessment for companies and countries. The methodology facilitates the analysis of key categories: energy, emissions, water, materials, and waste. A quantitative analysis of circularity, including a sensitivity analysis, is conducted at the macro level, identifying critical areas and the most influential factors for the circular economy. Based on this analysis, existing national strategies are evaluated, and implementation plans with specific measures are developed. This is followed by micro-level implementation, which involves techno-economic assessment of circular projects. Using this methodology, coordinated improvements in circularity are achieved at all levels. The methodology was tested in Slovenia, where the national circularity index revealed stable performance over five years, averaging slightly above 50 points out of 100. Analysis identified significant improvement potential in areas such as energy and emissions, aligning with the country's focus on decarbonization and energy efficiency in its climate strategies. At the company level, circularity assessments highlighted critical challenges in renewable energy use and overall energy efficiency. The proposed measures showed potential for significantly improving circularity and reducing emissions, while the results provided valuable insights into the economic feasibility of these transitions.
Keywords: circular economy, integrated assessment framework, micro level, energy transition, renewable energy
Published in DKUM: 10.02.2025; Views: 0; Downloads: 3
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Keywords: energy flexibility, aluminium smelting, renewable energy, virtual battery, solar production
Published in DKUM: 17.12.2024; Views: 0; Downloads: 16
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Abstract: Purpose: This paper aims to forecast the availability of used but operational electric vehicle (EV) batteries to integrate them into a circular economy concept of EVs’ end-of-life (EOL) phase. Since EVs currently on the roads will become obsolete after 2030, this study focuses on the 2030–2040 period and links future renewable electricity production with the potential for storing it into used EVs’ batteries. Even though battery capacity decreases by 80% or less, these batteries will remain operational and can still be seen as a valuable solution for storing peaks of renewable energy production beyond EV EOL. Design/methodology/approach: Storing renewable electricity is gaining as much attention as increasing its production and share. However, storing it in new batteries can be expensive as well as material and energyintensive; therefore, existing capacities should be considered. The use of battery electric vehicles (BEVs) is among the most exciting concepts on how to achieve it. Since reduced battery capacity decreases car manufacturers’ interest in battery reuse and recycling is environmentally hazardous, these batteries should be integrated into the future electricity storage system. Extending the life cycle of batteries from EVs beyond the EV’s life cycle is identified as a potential solution for both BEVEOL and electricity storage. Findings: Results revealed a rise of photovoltaic (PV) solar power plants and an increasing number of EVs EOL that will have to be considered. It was forecasted that 6.27–7.22% of electricity from PV systems in scenario A (if EV lifetime is predicted to be 20 years) and 18.82–21.68% of electricity from PV systems in scenario B (if EV lifetime is predicted to be 20 years) could be stored in batteries. Storing electricity in EV batteries beyond EV EOL would significantly decrease the need for raw materials, increase energy system and EV sustainability performance simultaneously and enable leaner and more efficient electricity production and distribution network. Practical implications: Storing electricity in used batteries would significantly decrease the need for primary materials as well as optimizing lean and efficient electricity production network. Originality/value: Energy storage is one of the priorities of energy companies but can be expensive as well as material and energy-intensive. The use of BEV is among the most interesting concepts on how to achieve it, but they are considered only when in the use phase as vehicle to grid (V2G) concept. Because reduced battery capacity decreases the interest of car manufacturers to reuse batteries and recycling is environmentally risky, these batteries should be used for storing, especially renewable electricity peaks. Extending the life cycle of batteries beyond the EV’s life cycle is identified as a potential solution for both BEV EOL and energy system sustainability, enabling more efficient energy management performance. The idea itself along with forecasting its potential is the main novelty of this paper.
Keywords: circular economy, renewable electricity, storing renewable electricity, batteries, renewable energy
Published in DKUM: 04.10.2024; Views: 0; Downloads: 5
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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: 104; Downloads: 11
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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: 222; Downloads: 34
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