Cleaner Energy Systems最新文献

Nigeria seeks to transition to a low-carbon economy through the use of renewable energy resources and technologies. However, while some of the Nigerian government's recent policies have emphasized the need for the relative decoupling of energy systems in order to maximize renewable energy, others have concurrently bolstered fossil-fuel power generation as the country's energy system's centerpiece. This paper employs the Long-Range Energy Alternatives Planning Tool (LEAP) and the Announced Pledges Scenario (APS) to evaluate Nigeria's progress toward a carbon-neutral economy. The findings indicate that the transformation to a low-carbon economy offers enormous opportunities for enhanced energy access and the future expansion of fossil fuel infrastructure. Nevertheless, institutional inertia and coordination lapses create barriers within the energy systems, while inconsistent policy priorities and political-economic calculations generate further bias in favor of the currently dominant oil- and gas-based development. Renewable energy will ensure Nigeria reduces its reliance on fossil fuels, but the transition will be fraught with formidable obstacles. Therefore, accelerating carbon neutralization necessitates a suite of energy mitigation pathways at scales that allow for the flexible integration of all energy systems, particularly modern bioenergy and natural gas.

Membrane Capacitive DeIonization (MCDI) cells have proven to be advantageous in water desalination and ions removal. Therefore, the time has come to introduce an alternative water purification technique to reduce the global water shortage. MCDI is known to be environmentally friendly, energy efficient and economical. Besides its reduced energy footprint, recent applications underline the regenerated energy during the desorption phase, which makes the MCDI as a potential cleaner energy source. Thus, a large number of scientific publications addressing problems and enhancing the performance of an MCDI have been published. In this paper, we have developed a simple and inexpensive method to control the adsorption voltage of the cells. So, the ion adsorption/desorption mechanisms of the MCDI will be controlled by a variable charging voltage applied to the cell.The entire response of controlled MCDI integrated model was created and he simulated results were compared with the experimental ones in order to validate the results. Accordingly, the controller parameters were tuned using the genetic algorithm optimization technique, based on the integral time absolute error criterion. Furthermore, the experimental results reveal that the control of the cell had increased the salt retention by 50%, the quantity of removed salt by the energy unit was improved by 10%, and the cell energy ratio from 28% to 32%.

Türkiye has the long-term goal of transforming its power system to one that is cleaner, more secure and more affordable. According to this paper's scenario analyses, low-cost renewables can supply 55% of Türkiye's total electricity demand. Coupled with the electrification of end-use sectors, energy efficiency can reduce total power demand by 10% compared to a business as usual scenario by 2030. The paper assesses the social, economic, and environmental impacts of this transformation by soft linking a power system model with an applied computable general equilibrium model, using an updated input and output dataset, and employing a novel analysis of job creation and fossil fuel externalities. The power system transformation significantly improves social welfare with net socioeconomic benefits estimated at 1% of GDP by 2030. Positive impacts include a reduction in human health and climate change externalities by a third, which are further enhanced by wage income growth that is driven by higher skilled and better paid jobs. A carbon tax emerges as a critical instrument to realize these benefits whilst reducing the power sector's emissions to 2030. The assessment should be expanded with more ambitious clean energy technology deployment for the entire energy system to operationalize Türkiye's Paris-aligned 2053 net-zero emission target and just transition policies.

The study aims to analyze a futuristic view of the automobile industry conducive to the much-needed penetration of Electric Vehicles (EVs) as per the current environmental and economic scenario. The study suggests the roll-out of EVs in tandem with the supporting Charging Infrastructure, which is a prerequisite for adopting the former. Although transport electrification is a much-accentuated and researched solution to the deteriorating environment and plummeting conventional resources, the design, production, manufacturing, use, degradation, and disposal of an exponential number of lithium-ion batteries for the same have environmental, economic, and social impacts. Thus, emphasis has been made on the sustainable use of charging infrastructure that curbs unnecessary and early battery aging from fast charging technology. Battery swap requests at a Battery Swapping Station (BSS) can be served via batteries from either available battery stock or by charging previously incoming discharged batteries. The study suggests an optimal strategy for the same via a mathematical model representing the operation cost of a BSS consisting of three components, namely, cost of battery utilization, damage cost associated with different charging methods, and dynamic electricity cost. The solution to the multiobjective optimization problem gave the optimum number of batteries that should be used from the battery stock and the charging decision for incoming discharged batteries, given the possible charging options and the constraints on demand satisfaction. Finally, the results from two different optimization tools, Solver in MS Excel and Lingo software, were compared.

This study investigates the conflicts between decarbonization by renewable energy use and local environmental preservation. It also proposes the policy implication for the introduction of offshore wind turbines in Japan. In 2020, the Japanese government declared its goal to achieve zero greenhouse gas emissions by 2050. Subsequently, the interest in renewable energy, such as offshore wind power, has been growing. However, coastal communities have concerns about the negative impact of offshore wind turbines on the landscapes, health, and the environment, and often oppose the construction of offshore wind turbines. In Europe—an advanced region of offshore wind power—there are many studies on its social acceptance; however, Japan records few cases of acceptance. This study conducted a nationwide online survey and a choice experiment for Japanese respondents. It found that offshore wind turbines are positively evaluated in terms of climate change mitigation, but negatively in terms of their impact on the landscape. Heterogeneity was also observed in people's preferences.

For almost a half-decade, the methodology of Pinch Analysis (PA) and heat integration (HI) has been used to optimize the requirements of external utilities. Though much has been done, optimizations under uncertain conditions still need more work, discussion, and practical implementation. In most of the HI problems, it has been observed that variation in the minimum driving force affects the shape of the source and sink profile eventually the heat exchanger network (HEN) design. Due to changing operating conditions, human errors, and sometimes poor maintenance, it has been experienced that the process plants along with their equipment and vessels do not operate at the desired value upon which they are expected to run. The parameters with variations and uncertainties due to disturbances in the process plants need to be addressed for the desired product output. In this work, the concept of PA has been unified with robust optimization (RO) to target the utility requirements in HEN optimization where the uncertainties in the heat capacity flow rate $F$ and supply temperatures $T_{in}$ of the source streams are considered. The developed nominal forms of mathematical programming are converted into the deterministic robust counterpart equivalents to incorporate the uncertainties whose set of variations is known. RO is an optimization technique where the information of accurate probability distribution needs not be known; rather, it works in a defined set of uncertainty ensuring the feasibility of the solution. Using two examples from the literature, the developed models have been solved and results for the solutions against the range of uncertainties in parameters have been established. The produced data demonstrates, in the case of uncertain inlet temperature the rise in total utilities is 115% and 225% in examples 1 and 2 for worst case is calculated. Plots of budget parameter Γ vs the utility requirement have also been compared with results. Application of this model will further assist the plant engineers/managers in deciding the requirements of hot utilities and cold utilities under the parametric uncertainties as needed.

Hybrid renewable energy systems (HRES) is a frequently discussed topic in the energy sector world due to the rising energy prices and crisis. The cost-effective and uninterrupted power supply is the major challenge of the energy sector which is to be dealt with in this assessment work. In this study, an assessment of a solar-biomass on-grid HRES is carried out for Hattar Industrial Zone phase-VII. Historical electricity demand for different industries in Hattar industrial estate is accounted to develop the year-round load curve. The peak demand of about 130,000 kW with a reserve margin of 30% is considered as the base for techno-economic analysis of the proposed hybrid system. The energy model of this hybrid system is developed in Hybrid Optimization Model for Electric Renewables (HOMER). The solar biomass on-grid hybrid system with different component sizes is analysed to get an optimal configuration having the least cost of energy (COE), net present cost (NPC) and initial capital investment (ICI). Moreover, the sensitivity analysis of the optimized configuration is carried out further against the input resource parameters like solar irradiance and biomass resource availability. Optimization and, sensitivity analysis resulted out that the 70,000 kW solar PV, 7000 kW biogas generator with the open-source grid is the most viable hybrid system option for the Hattar industrial zone phase-VII. This optimal system has the least COE, i.e., Rs 14.11/kWh ($0.092/kWh) amongst all the proposed configurations with a payback period of 4.6 years and there is a significant reduction in carbon emissions.

Energy is a cornerstone and strategic tool to meet basic human needs and address many global development challenges. However, ensuring energy supply while limiting energy's contribution to environmental change is a major challenge confronting the energy sector in many developing countries. The challenge is more severe in Sub-Saharan Africa, where about 900 million people still rely on biomass fuels for cooking. Cooking with biomass might not be a problem by itself. Instead, it is the inability to use biomass energy resources sustainably. Improving the opportunities for modern and sustainable energy use is, thus, an essential prerequisite to enhancing the livelihoods of the poor. This study examines the determinants of household energy choice in the Semien Mountains National Park and adjacent districts in Northwest Ethiopia. A survey of 420 randomly selected households was administered using a semi-structured questionnaire. Descriptive statistics and a multivariate probit model were employed to analyze the data. Results showed that households' energy utilization pattern is skewed towards biomass fuels, particularly fuelwood (87%), while only a few households use charcoal (32%) and electricity (17%) for domestic chores. The study also shows that the majority (87%) of households collect all of their energy sources themselves, while 13% purchase from the market. In addition, the results show that about 77% of households perceived that fuelwood availability had decreased over time owing to deforestation. Estimates of the multivariate probit model showed that a mix of factors, including age, gender, household size, education, income, access to electricity, off-farm activities, access to market, distance to forest, and housing type, determine household cooking energy choice and the extent of dependency on it. Thus, the findings proved that local communities prefer fuel stacking rather than ascending the energy ladder. Based on the results, the study recommended that the local community be encouraged to use biomass fuels in a more environmentally friendly way and use sustainable and affordable modern energy sources.

The extremely hot and humid nature of the Gulf Cooperation Council necessitates cooling. There is a dearth of literature that addresses the energy consumption profile of high-rise buildings in this climate, which is important for the fair distribution of costs among end users according to their usage. This study aims to address the literature gap by studying the cooling requirements of a representative tall residential building in an extremely hot and humid climate. Sensitivity analysis of 14 building characteristics against annual cooling load reveals that Window-to-Wall-Ratio (WWR) and orientation parameters sway anywhere between the most significant and the least significant attributes, respectively. From the analysis, a significant discrepancy in cooling consumption has been observed between the first and top floors, with an average of around 140% more. Furthermore, sensitivity analysis revealed that equipment power density is a dominating factor at the apartment level, while the floor number dominates in the whole building. A parametric analysis indicates that building rotation can increase or decrease energy consumption up to 4.0 kWh/m²/month or 5.6 kWh/m²/month, depending on the apartment's location. This study would facilitate especially the planning stage of the buildings in a whole district and operation-related decisions of the corresponding district cooling plant in the hot and humid climate.

Solar concentrating power is an important weapon for facing the energy crisis and environmental issues. Greece is a country with great solar potential and thus it is an ideal candidate for the development of important solar concentrating power plants. These plants present the advantage of easy energy storage with thermal storage tanks, something beneficial for the production of a relatively stable electricity production profile, something critical for the further development of renewable energy systems. The objective of the present work is the detailed investigation of the solar concentrating technologies in different Greek locations in order to define in which locations solar concentrating power is a promising solution. Moreover, three typical solar concentrating technologies are studied and more specifically the parabolic trough collector (PTC), the linear Fresnel reflector (LFR) and the solar DISH. Thirteen different Greek regions are investigated by using hourly weather data from the typical meteorological year (TMY). The solar potential, the available irradiation, the useful heat production, the electricity production and the exergy production, as well as the respective efficiency indexes and the levelized cost of electricity (LCOE), are calculated. It is important to highlight that this study is focused on the systems of small capacity which are ideal for distributed renewable power production. It was concluded that the most efficient and economically feasible technology is the solar DISH, with the PTC to follow and LFR to be the last choice. Moreover, southern Greece is found to be a better choice for the installation of solar-concentrating power plants compared to northern Greece. More specifically, in the Southern Aegean Sea, it was calculated that the specific electricity production is 253.0 kWh/m² with PTC, 160.7 kWh/m² with LFR and 296.8 kWh/m² with DISH, while the LCOE at 0.0882 €/kWh with PTC, 0.1046 €/kWh with LFR and 0.0843 €/kWh with DISH.