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In accordance with the Korean 2050 carbon neutrality scenarios, renewable energy accounts for 70.8 % and 60.9 % of the total future electricity production in scenarios A and B, respectively. However, renewable energy is relatively more uncontrollable than other generators, such as gas turbines and power plants, and this condition can lead to grid instability, including electricity waste and blackouts. Here, we analyzed the issues by designing and simulating a South Korean energy supply and demand system. Uncontrollable renewable energy causes a mismatch between power supply and demand. We resolved this issue by increasing the capacity of controllable generators, ultimately resulting in unwanted excess energy generation of 302 TWh and 281 TWh for Scenarios A and B, respectively. Therefore, an energy storage system (ESS), including a battery and electrolysis facility, was added to stabilize the total electrical grid. A stabilized electrical grid provides economic benefits, such as reduced levelized cost of electricity and net present cost, particularly by the battery ESS. Electrolysis can generate hydrogen to be used as a fuel of controllable energy, increasing the stability of the total grid by reducing excess energy more practically than the battery ESS does. [ABSTRACT FROM AUTHOR]

Hydrogen, a crucial clean and renewable energy source, addresses pressing challenges of energy security and environmental pollution. Water electrolysis for hydrogen production is a promising approach to satisfy the growing demand for sustainable energy. This study uniquely performs a comprehensive techno-economic analysis of hydrogen production using both Alkaline and Proton Exchange Membrane (PEM) electrolyzers, a first in the field to evaluate their performance comprehensively with advanced Multi-Criteria Decision-Making (MCDM) techniques. Leveraging TOPSIS, WASPAS interval methods, and the Best Worst Method (BWM) with fuzzy logic, this research introduces a novel evaluation framework that incorporates a wide-ranging set of factors, including environmental, technical, technological, economic, and social aspects, divided into 30 sub-criteria. These insights offer a comprehensive understanding of each electrolyser's strengths and weaknesses, helping stakeholders make informed decisions about cost reduction in hydrogen production technologies. This has not been done before. Although cost results favour Alkaline electrolysers, PEM electrolysers are attractive for specific applications where their benefits justify the higher initial cost, choosing between Alkaline and PEM electrolysers dependent on a given hydrogen production project's requirements. [ABSTRACT FROM AUTHOR]

This critical review examines the potential of household biogas technology in Africa, focusing on biogas production and techno‐economic feasibility studies. The review highlights the benefits of biogas technology, including renewable energy generation, waste management, and improved public health. A significant portion of Africa's rural population, approximately 60%, grapples with limited access to reliable power sources. The study analyzes various biogas production systems, including anaerobic digesters and biomass gasifiers, and evaluates their economic viability in different African contexts. The review identifies key factors influencing the adoption of household biogas technology, including policy and regulatory frameworks, financing mechanisms, and public awareness. Biogas production stands out as one of the promising renewable energy sources. However, it also discusses the challenges and limitations of implementing this technology on a continental scale. The study analyzes various biogas production systems, including anaerobic digesters and biomass gasifiers, and evaluates their economic viability in different African contexts. The review identifies key factors influencing the adoption of household biogas technology, including policy and regulatory frameworks, financing mechanisms, and public awareness. The study concludes by recommending strategies for scaling up biogas technology in Africa, including capacity building, technology transfer, and innovative financing models. The review aims to provide a comprehensive resource for researchers, policymakers, and practitioners working towards sustainable energy solutions in Africa. [ABSTRACT FROM AUTHOR]

To advance wave energy devices towards commercialization, it is essential to optimize their design to enhance system performance. Additionally, a thorough economic evaluation is crucial for making these technologies competitive with other renewable energy sources. This study focuses on the techno-economic optimization of an innovative inertial system, the so-called SWINGO system, which is based on gyropendulum technology. SWINGO stands out due to its high energy efficiency in multi-directional installation sites, where wave directions vary significantly throughout the year. The study introduces the application of a multi-objective Evolutionary Algorithm (EA), specifically the Non-dominated Sorting Genetic Algorithm II (NSGA-II), to optimize the techno-economic performance of the SWINGO system. This approach aims to identify optimal design parameters that maximize energy extraction while considering economic viability. By deriving a Pareto frontier, a set of optimal devices is selected for further analysis. The performance of the SWINGO system is also compared to an alternative (mono-directional) inertial wave energy converter, the Inertial Sea Wave Energy Converter (ISWEC), to highlight the differences in techno-economic outcomes. Both systems are evaluated at two different installation sites: Pantelleria island and the North Sea in Denmark, with a focus on the directional wave scatter at each location. [ABSTRACT FROM AUTHOR]

Biomass pyrolysis is the most effective process to convert abundant organic matter into value-added products that could be an alternative to depleting fossil fuels. A comprehensive understanding of the biomass pyrolysis is essential in designing the experiments. However, pyrolysis is a complex process dependent on multiple feedstock characteristics, such as biomass consisting of volatile matter, moisture content, fixed carbon, and ash content, all of which can influence yield formation. On top of that, product composition can also be affected by the particle size, shape, susceptors used, and pre-treatment conditions of the feedstock. Compared to conventional pyrolysis, microwave-assisted pyrolysis (MAP) is a novel thermochemical process that improves internal heat transfer. MAP experiments complicate the operation due to additional governing factors (i.e. operating parameters) such as heating rate, temperature, and microwave power. In most instances, a single parameter or the interaction of parameters, i.e. the influence of other parameter integration, plays a crucial role in pyrolysis. Although various studies on a few operating parameters or feedstock characteristics have been discussed in the literature, a comprehensive review still needs to be provided. Consequently, this review paper deconstructed biomass and its sources, including microwave-assisted pyrolysis, and discussed the impact of operating parameters and biomass properties on pyrolysis products. This paper addresses the challenge of handling multivariate problems in MAP and delivers solutions by application of the machine learning technique to minimise experimental effort. Techno-economic analysis of the biomass pyrolysis process and suggestions for future research are also discussed. [ABSTRACT FROM AUTHOR]

Abstract Hydrogen, a crucial clean and renewable energy source, addresses pressing challenges of energy security and environmental pollution. Water electrolysis for hydrogen production is a promising approach to satisfy the growing demand for sustainable energy. This study uniquely performs a comprehensive techno-economic analysis of hydrogen production using both Alkaline and Proton Exchange Membrane (PEM) electrolyzers, a first in the field to evaluate their performance comprehensively with advanced Multi-Criteria Decision-Making (MCDM) techniques. Leveraging TOPSIS, WASPAS interval methods, and the Best Worst Method (BWM) with fuzzy logic, this research introduces a novel evaluation framework that incorporates a wide-ranging set of factors, including environmental, technical, technological, economic, and social aspects, divided into 30 sub-criteria. These insights offer a comprehensive understanding of each electrolyser's strengths and weaknesses, helping stakeholders make informed decisions about cost reduction in hydrogen production technologies. This has not been done before. Although cost results favour Alkaline electrolysers, PEM electrolysers are attractive for specific applications where their benefits justify the higher initial cost, choosing between Alkaline and PEM electrolysers dependent on a given hydrogen production project's requirements.

ABSTRACT The Additively‐Manufactured, System‐Integrated Tip (AMSIT) project is leveraging the flexibility of 3D printing to integrate several technologies in a wind turbine blade tip, while reducing the levelized cost of electricity (LCOE) produced. The design integration is demonstrated for a 200‐kW–scale turbine with 13‐m blades, with the outer 15% of the blade replaced with a 3D‐printed design. Aerodynamic performance is enhanced without increasing swept area through inclusion of a winglet and surface texturing, both challenging for traditional manufacturing. Longevity and durability are improved through integrated lightning and leading edge erosion protection. Increased power, reduced repair frequency, and ease of repair through blade modularity all contribute to reduced LCOE. The analysis is also extended to modern MW‐scale designs to estimate the impact of the technology at scale, demonstrating the potential to reduce LCOE significantly for modern onshore turbines, with even higher potential savings offshore.

The current study proposes a model of an autonomous HRFS installed on different sites in 20 Saudi cities powered by renewable clean energy sources. The station is fully powered by photovoltaic (PV) panels and wind turbines involving an electrolyzer and hydrogen tank for producing and storing hydrogen. Three scenarios are investigated to propose an optimized model, namely Scenario 1 containing (PV-Wind-Battery) system, Scenario 2 with (Wind-Battery) technologies, and Scenario 3 with (PV-Battery) components. The HRFS is expected to feed the load hydrogen demand of 25 hydrogen cars with a storage tank capacity of 5 kg. The simulation is carried out using the well-known HOMER software and the description of the technical parameters of the renewable plant together with a detailed economic feasibility for the investigated cities are also performed. Furthermore, the optimization process executed demonstrates a competitive levelized cost of energy (LCOE) and levelized cost of hydrogen (LCOH) especially for the third scenario with a LCOH varying within $12–15.9/kg and LCOE in range $ 0.332–0.414/kWh, for all 20 cities. For instance, encouraging lowest values of net present cost (NPC) and LCOE are obtained for the futuristic NEOM mega city relatively to the first and third scenarios with values (NPC = $1,576,000, LCOE = $ 0.627/kWh) and (NPC = $830,494, LCOE = $ 0.332/kWh), respectively. On another hand, thorough analysis of PV/Wind hydrogen technoeconomic operation is provided including improvements recommendations, scenarios comparison and environmental impact discussion. [ABSTRACT FROM AUTHOR]

The transition to sustainable energy has ushered in the era of electrofuels (e-fuels), which are synthesised using electricity from renewable sources, water, and CO2 as a sustainable alternative to fossil fuels. This paper presents a systematic review of the techno-economic (TEA) and life cycle assessments (LCAs) of e-fuel production. We critically evaluate advancements in production technologies, economic feasibility, environmental implications, and potential societal impacts. Our findings indicate that while e-fuels offer a promising solution to reduce carbon emissions, their economic viability depends on optimising production processes and reducing input material costs. The LCA highlights the necessity of using renewable energy for hydrogen production to ensure the genuine sustainability of e-fuels. This review also identifies knowledge gaps, suggesting areas for future research and policy intervention. As the world moves toward a greener future, understanding the holistic implications of e-fuels becomes paramount. This review aims to provide a comprehensive overview to guide stakeholders in their decision-making processes. [ABSTRACT FROM AUTHOR]

The article examines the feasibility of implementing standalone hydrogen-based renewable energy systems in Spanish residential buildings, specifically analyzing the optimization of a solar-battery and solar-hydrogen system for a building with 20 dwellings in Spain. The study initially assesses two standalone setups: solar-battery and solar-hydrogen. Subsequently, it explores scenarios where these systems are connected to the grid to only generate and sell surplus energy. A scenario involving grid connection for self-consumption without storage serves as a benchmark for comparison. All system optimizations are designed to meet energy demands without interruptions while minimizing costs, as determined by a techno-economic analysis. The systems are sized using custom software that incorporates an energy management system and employs the Jaya algorithm for optimization. The findings indicate that selling surplus energy can be economically competitive and enhance the efficiency of grid-connected self-consumption systems, representing the study's main innovation. The conclusion highlights the economic and technical potential of an autonomous hybrid energy system that includes hydrogen, with the significant remaining challenge being the development of a regulatory framework to support its technical feasibility in Spain. • PV-battery and PV-H2 self-sufficient stand-alone systems for a 20-dwelling building. • Residential energy demand based on actual annual four-dwelling metering data. • Sale of surplus generation to the grid from a renewable stand-alone system. • Custom-made software and Jaya algorithm for system simulation and cost optimization. • PV-H2 integration in residential buildings leads to a reduction in grid dependency. [ABSTRACT FROM AUTHOR]

Microgrids and hybrid renewable energy systems play a crucial role in today's energy transition. They enable local power generation and distribution, reducing dependence on large centralized infrastructures, can operate independently or connected to a grid, and can provide backup power, thus increasing system resilience. In addition, they combine multiple renewable energy sources, such as solar, wind, hydro, and biomass, to maximize the efficiency and reliability of the supply, and are also adaptable to location-specific conditions, taking advantage of locally available energy resources and reducing the need for energy imports. Moreover, they contribute to decarbonization goals by offering a cleaner and more sustainable alternative. In this article, a documentary review is presented on the interaction of Homer Pro software 3.16.2 (July 2023), used for the design of hybrid renewable energy systems (HRES), with other methods of optimization or sizing. Allusion is made to the type of architecture in the most prominent clean and fossil source configurations, the levelized cost, net annual cost, and maintenance and capital investment cost. A comparison is made among the works reported in the last five years regarding the use of this software tool, based on load demand, geographical area, renewable energy sources, fossil sources, and objective functions, applied to the educational, rural, and industrial sectors. It is shown that India is one of the countries that has reported the most number of HRES techno-economic environmental analysis works, and that the case studies have focused approximately 47% on rural areas, 20% on educational agencies, 14% on commerce and industry, and 29% on urban buildings. [ABSTRACT FROM AUTHOR]

The concerns over greenhouse gas emissions, environmental impacts, climate change, and sustainability continue to grow. As a result of countermeasures, many modern gas turbine power plants and combined cycle power plants are considering to use hydrogen as a clean fuel alternative to fossil fuels in the power plant industry. We assessed the implications of such transition from natural gas to hydrogen as fuel in a gas turbine power plant's balance of plant (BOP) equipment. Using the DWSIM process simulation software and the methodology of compression power changes against different gas compositions, the impact of blending hydrogen with natural gas on temperature differentials, energy consumption, adiabatic efficiency, compression power, and economic implications in gas turbine power plants were examined in this paper. We discovered, through analysis, that there was not a noticeable boost in compression power or energy consumption when 50% hydrogen and 50% natural gas were blended. Similarly, there was no discernible difference in temperature differentials or adiabatic efficiency when 30% hydrogen and 70% natural gas were blended. Moreover, mixing 50% hydrogen and 50% natural gas did not result in a noticeable cost climb. In addition, the techno-economic analysis presented in this paper offered valuable insights for power plant engineers, power generation companies, investors in energy sectors, and policymakers, highlighting the nature of the fuel shift and its implications on the economy and technology.

The interdependence between water and energy (water-energy nexus) has been identified as one of the major challenges at European level, with roadmaps calling for the development of integrated approaches in this sector. The increase in river temperature is at the heart of this nexus, with anthropogenic thermal pollution adding to the effect of global warming. River Water Heat Pumps can play a major role by decarbonising district heating network (DHN) while actively cooling the aquatic resource. Hence, the objective of this short communication is to identify the scientific challenges to be met and the progress to be achieved considering the current state of the art. To illustrate the point, a rapid evaluation of the potential is performed for the city of Lyon in France resulting in an achievable cooling of ∼1.5 K which is above the minimum threshold to see an effect on aquatic ecosystem while the CO2 savings are significant for the DHN (∼ divided by a factor of 10). Because of its holistic nature, the impact assessment of such a system implies considering a wide diversity of indicators: energy, environmental, economics and sociological that need to be appropriately defined and quantified. In each field, progress beyond the state of the art to be performed has been identified, e.g. 4E analysis, cold water plume dispersion, integration of biodiversity in LCA.

The development of sustainable biofuels can help to reduce the reliance on fossil fuels and mitigate the impact of climate change. This study analyzes bioethanol production from agro-forestry residual biomass, namely eucalyptus residues and corn stover. The study includes process simulation using Aspen Plus software, followed by economic analysis and life cycle assessment (LCA) with the help of SimaPro software and by applying the environmental footprint (EF) 3.0 method. The economic analysis on the biorefinery's economic viability, equipment, and production costs reveals a positive decision for bioethanol production from eucalyptus residues due to logistical and transportation costs. The minimum ethanol selling price (MESP) obtained was 2.19 €/L and 2.45 €/L for eucalyptus residues and corn stover, respectively. From the LCA with a functional unit of 1 MJ of ethanol, bioethanol production from eucalyptus residues results in a single score impact of 37.86 µPt, whereas for corn stover, it is 33.47 µPt. In the climate change impact category, the eucalyptus residues scenario has an impact of 0.264 kg CO2 eq/MJ ethanol while corn stover leads to 0.254 kg CO2 eq/MJ ethanol. In-situ enzyme production, heat integration, and the use of renewable energy sources were also analyzed. Combining in situ enzyme production with renewable energy sources lowers CO2 equivalent emissions by 89% for both feedstocks, in comparison to the base-case scenario. [ABSTRACT FROM AUTHOR]

Abstract To achieve the Sustainable Development Goals by 2030, low-income sub-Saharan African countries urgently need to electrify. Biogas production from anaerobic digestion could make a contribution to a solution to improved electricity generation and access in these regions. This study evaluates its feasibility using Malawi as a case study. The aim is to provide households with a continuous supply of gas for cooking and electricity. The study examines different sizes of fixed dome reactors (3, 6, 12 m3) and assumes individual household ownership of 2, 4, and 6 cows. Several feedstocks and conditions are considered, such as cow dung alone, co-generation of cow dung with human faeces, cow dung with grass, and cow dung with maize residue. The economic benefits of selling biogas and fertilisers are calculated, and the cost of construction for different sizes of reactors is determined. Results show that co-generation of cow dung and grass silage in the reactor of 12 m3 with six cows has a positive net present value (NPV) of $8962, while for a small farm with a 6 m3 reactor capacity, co-digestion of cow dung with maize residue is preferable. The feasibility of the technology depends heavily on current national economic conditions, such as inflation, electricity prices, and construction material costs. A sensitivity analysis estimated that a 25% increase in the cost of electricity could increase the net present value (NPV) from − $3345 to $1526 for the generation of biogas from cow dung alone. Overall, this technology could have a significant impact on the lives of low-income households in sub-Saharan Africa by improving their access to electricity and providing a source of income through the sale of biogas and digestate.

In developing countries like Ghana, the conversion of waste into energy is gaining greater interest among policy makers and researchers. The present study investigates the feasibility of producing electricity and/or fuels from a hybrid waste-to-energy pilot plant located in the Ashanti Region of Ghana. The plant integrates three technologies: anaerobic digestion, pyrolysis and solar PV. The plant has the potential to produce both energy and fuels such as green hydrogen, refuse derived fuels, bio-compressed natural gas and compost. Thus, this study compares the financial feasibility of three scenarios—generating electricity and fuels, generating electricity alone and generating fuels alone—by modelling their energy output and financial performance using RETSCREEN expert 6.0.7.55 and Microsoft Excel 2019 softwares. The results indicate that the multiple products of electricity and fuels provide higher investment interest with a Net Present Value in excess of EUR 13 million and a payback period of 12 years compared to the electricity-only model. Also, converting electricity into fuels alone also provides substantial benefits which can be explored. However, the Levelized Cost of Energy, ranging from 0.3 to 0.68 EUR/kWh, is far above the average residential End User tariff. Overall, this study provides an important methodology for assessing the potential products of future projects. [ABSTRACT FROM AUTHOR]

This article proposes a hybrid energy model comprising of various stand-alone and grid-connected energy systems including grid-connected hybrid, off-grid hybrid, fuel cell-photovoltaic, fuel cell-wind turbine, photovoltaic-wind turbine, wind turbine, and photovoltaic to fulfill the power requirements of an educational institute in Pakistan. These systems have been developed, simulated, and optimized for techno-economic feasibility, taking into consideration the electricity demand profile, geographic regions, and climatic data. A sensitivity analysis has been conducted to determine the most economical systems for producing 0.90079 MWh of energy per day. Simulation results show that the net present cost of the grid-connected hybrid system is between M$ 1.536859 and M$ 6.818162, while the cost of energy is between $ 0.155 and $ 0.3749 per kWh. The fuel cell -wind turbine system incurs a maximum energy cost of $ 0.3749/kWh. The solar and grid-connected hybrid systems offers the lowest net present cost and cost of energy, which are M$ 1.536859 and $ 0.155/kWh, respectively. The research findings suggest that utilizing photovoltaic, wind, and fuel cells is a more feasible and economical strategy due to system benefits. The study also showed the viability and efficiency of using solar and wind resources for hydrogen production and power generation. Additionally, the study demonstrated that hydrogen is a more affordable option for long-term energy storage than batteries. • Seven different energy systems are considered in this research. • Sensitivity investigation is conducted in effort to determine the most economic systems. • Cost of energy is found to be between 0.155 and 0.3495 $/kWh. • Maximum cost of energy is accounted by wind turbine system 0.3495 $/kWh. • Hydrogen is a more affordable long-term energy storage alternative than batteries. [ABSTRACT FROM AUTHOR]

Electricity generation from photovoltaic (PV) in Latvia is currently below the necessary capacity required to contribute to achieving climate neutrality by 2050. However, photovoltaic offer households and companies the opportunity to align their electricity consumption with environmental goals while supporting the European Green Deal objectives. In recent years, there was a growing interest in the installation of photovoltaic microgenerators in Latvia. By June 2023, the total number of households microgenerators connected to the grid has reached 15,000, boasting a collective production capacity exceeding 120 MW. This significant increase is in stark contrast to the situation 5 years ago when Latvia had a mere 3 MW of photovoltaic capacity. Several factors contributed to this growth, including a surge in electricity prices, at times surging more than tenfold, and the implementation of renewable energy (RE) use support measures to facilitate the acquisition of RE systems. Furthermore, 2023 witnessed numerous amendments to Latvia's energy policy documents and the introduction of the concept of citizen energy communities (CEC), indicating a growing emphasis on harnessing solar energy potential in the country. However, it remains crucial to base these endeavors on accurate, economically viable information regarding solar technologies, their costs and their anticipated long-term outcomes. This manuscript aims to provide an overview of the grid-connected potential of rooftop photovoltaic systems within a Latvian urban setting. Through extensive research, a model has been developed, employing a thoroughly tested simulation program for evaluating the generation capacity of photovoltaic systems. This model considers real electricity consumption data, the existing infrastructure and economic factors. The findings affirm the technical and economic viability of urban rooftop photovoltaic systems within the Latvian context. It has been established that the implementation of such citizen energy communities energy systems holds significant potential. These systems have the potential to be a promising solution for future electricity generation, addressing some of the demands while relieving strain on external power grids. However, the full potential can only be realized with improved infrastructure, and the system's profitability is heavily contingent on market dynamics and political conditions. This study may also be applicable to other photovoltaic systems facing similar climate conditions. [ABSTRACT FROM AUTHOR]

In pursuit of Finland's carbon neutrality objective by 2035, integrating renewable energy sources into the power grid is essential. To address the stochastic nature of these resources, additional sources of flexibility are required to maintain grid stability. Meanwhile, district heating network (DHN) operators in Finland are decommissioning fossil fuel-based combined heat and power plants (CHPs) and electrifying heating systems with heat pumps (HPs) and electric boilers. A techno-economic assessment and the optimized operation of DHN-connected HPs and electric boilers in providing ancillary balancing services were explored in this study. The primary goal was to maximize the potential revenue for DHN operators through participation in the day-ahead electricity market and frequency containment reserve (FCR) balancing markets. Three interconnected DHNs in the Helsinki metropolitan area were optimized based on 2019 data and each operator's decarbonization strategies for 2025. HPs are expected to achieve the highest profit margins in the FCR-D up-regulation market, while electric boilers could generate substantial profits from the FCR-D down-regulation market. In contrast to other balancing markets studied, the FCR-N market exhibited limited profit potential. Sensitivity analysis indicated that spot electricity prices and CO2 emission allowance prices significantly influence the profitability derived from balancing markets. [ABSTRACT FROM AUTHOR]

Nowadays, with the need for clean and sustainable energy at its historical peak, new equipment, strategies, and methods have to be developed to reduce environmental pollution. Drastic steps and measures have already been taken on a global scale. Renewable energy sources (RESs) are being installed with a growing rhythm in the power grids. Such installations and operations in power systems must also be economically viable over time to attract more investors, thus creating a cycle where green energy, e.g., green hydrogen production will be both environmentally friendly and economically beneficial. This work presents a management method for assessing wind–solar–hydrogen (H2) energy systems. To optimize component sizing and calculate the cost of the produced H2, the basic procedure of the whole management method includes chronological simulations and economic calculations. The proposed system consists of a wind turbine (WT), a photovoltaic (PV) unit, an electrolyzer, a compressor, a storage tank, a fuel cell (FC), and various power converters. The paper presents a case study of green hydrogen production on Sifnos Island in Greece through RES, together with a scenario where hydrogen vehicle consumption and RES production are higher during the summer months. Hydrogen stations represent H2 demand. The proposed system is connected to the main power grid of the island to cover the load demand if the RES cannot do this. This study also includes a cost analysis due to the high investment costs. The levelized cost of energy (LCOE) and the cost of the produced H2 are calculated, and some future simulations correlated with the main costs of the components of the proposed system are pointed out. The MATLAB language is used for all simulations. [ABSTRACT FROM AUTHOR]

This work undertakes a techno-economic comparative analysis of the design of photovoltaic panel/wind turbine/electrolyzer-H2 tank–fuel cell/electrolyzer-H2 tank (configuration 1) and photovoltaic panel/wind turbine/battery/electrolyzer-H2 tank (configuration 2) to supply electricity to a simulated house and a hydrogen-powered vehicle on Jeju Island. The aim is to find a system that will make optimum use of the excess energy produced by renewable energies to power the hydrogen vehicle while guaranteeing the reliability and cost-effectiveness of the entire system. In addition to evaluating the Loss of Power Supply Probability (LPSP) and the Levelized Cost of Energy (LCOE), the search for achieving that objective leads to the evaluation of two new performance indicators: Loss of Hydrogen Supply Probability (LHSP) and Levelized Cost of Hydrogen (LCOH). After analysis, for 0 < LPSP < 1 and 0 < LHSP < 1 used as the constraints in a multi-objective genetic algorithm, configuration 1 turns out to be the most efficient loads feeder with an LCOE of 0.3322 USD/kWh, an LPSP of 0% concerning the simulated house load, an LCOH of 11.5671 USD/kg for a 5 kg hydrogen storage, and an LHSP of 0.0043% regarding the hydrogen vehicle load. [ABSTRACT FROM AUTHOR]

As it stands, the UK has no commercialised process capable of recycling waste glass fibre reinforced thermosets, resulting in disposal via landfill or energy from waste facilities. Thermal recycling within a fluidised bed process has been demonstrated to successfully recover clean glass fibre from composite waste materials, such as wind turbine blades, and successfully reuse it as a reinforcement phase in second life composites. If brought to a commercial scale, this technology has the potential to divert up to 1200 kt of mixed glass fibre reinforced plastics (GRP) waste and an additional 240 kt of wind blade waste away from UK landfill sites over the next fifteen years, while offsetting the environmental impact and raw material consumption of virgin glass fibre production. Despite this, commercialisation and long-term success depend on economic viability and resilience of the recycling technology, ensuring that sufficient value is added to offset costs required to bring recyclate products to market. In this study, techno-economic analysis was used to analyse the economic outlook for at scale fluidised bed recycling plants within the context of the current and future UK glass fibre reinforced plastic waste landscape. It was found that fluidised bed recycling plants operating well within current UK waste volumes can maintain gate fees that are competitive with landfill while producing recycled glass fibre (rGF) at less than 50% of the prices of virgin counterparts. Plants processing single waste streams, such as wind blades, can maintain long term profitability despite irregular flow of waste feedstock availability. Despite higher transportation cost, total recycling costs are lower for national level plants. Therefore, it is recommended to accept composites from multiple waste streams to maximise operating capacity, profits and return on investment.

Agrivoltaics (AV) combines photovoltaic (PV) electricity generation with agriculture on the same land. In Chile, despite high potential, AV is not yet commercialized due to high investment cost. To close the remaining cost gap to conventional PV, we shed light on a set of AV specific synergies in the market segment of Small Distributed Generation Facilities. Through a techno-economic model, this paper monetizes AV synergies to derive the economic performance of a sun tracked AV system over blueberries for the PV stakeholder. The study reveals that tracked AV systems can be operated with an Internal Rate of Return (IRR) of 5.2% at the threshold of profitability. This is enabled due to the exploitation of synergies within the market segment that improve IRR for the PV stakeholder by 2.5%. Still, sun-tracked AV requires compulsory technology grants between 5 – 10 USD/MWh to be economically implemented. The results indicate the necessity for regulative adaption. Legislation must open agricultural land for AV project development to enable the commercialization.

Conventional chemicals and synthetic inputs have been identified with numerous environmental and human health hazards. These challenges have created increase in the search for better alternatives from different sources. In this paper, essential oil was studied as a prominent alternative with high levels of microbiological and antioxidant activities, and the potential to meet the replacement needs, since they are considered eco-friendly, cheaper, safer and healthier. Essential oils (EOs) have been identified for their vital relevance and uses in many areas ranging from pharmaceutical, medicinal, food flavoring and preservation. The potency of EOs and their viability for various applications are attributed to the constituent bioactive compounds, which constitute their active agents. EOs are mainly isolated and recovered from plant substrates by adopting different methods of extraction. This study presents a critical overview of the relevant and current trends in available literature concerning extraction methods for EOs. In this study, the methods for extracting essential oils, vis-à-vis their influence on production yields, qualities, compositions and bioactivities of products were reviewed. The study focused on the perspectives and prospects of Hyptis suaveolens, a renewable resource, with a view of bringing it to the limelight as a viable biological source of essential oil. It was found that extraction methods, as well as edaphic factors and geographical locations, have significant effects on the yields, qualities and chemical compositions of the essential oils obtained. The study further revealed that essential oil from Hyptis suaveolens exhibits strong bioactivities, which serve as the basis for its use to effectively check and control pests, insects, and other pathogenic organisms and for treatment of ailments like diarrhea, and stomach disorders. Therefore, it is recommended that viable, improved methods and processes for extracting essential oil from Hyptis suaveolens be successfully developed and deployed to access its accruing potential advantages, ranging from high production yields, economic gains (low cost and low energy consumption), high product quality and low environmental impact. This is expected to create a reliable alternative biological input, with the potential to replace the conventional synthetic chemicals in current use and thereby avoid the negative side effects of synthetics on non-targeted organisms, the environment and the economy. It would also contribute immensely to better control of carbon cycle and green and sustainable technology.

The ageing of coal-fired power stations in South Africa has led to regular power outages. Therefore, the country will need to urgently increase its electricity capacity to meet further energy demand from growing urbanization and population growth. This challenge has increased interest in alternative energy sources, such as renewable energy (RE). South Africa is gradually implementing appropriate renewable energy practices, reducing carbon emissions, cleansing the air, and assuring a more sustainable future. This paper summarizes the availability, current state, and future potential of renewable energy choices in South Africa. This paper also evaluates specific policy measures and government actions aimed at eliminating barriers and increasing renewable energy deployment in the future. It also considers the South African network's specialized techno-economic analysis. The findings show that South Africa is still heavily reliant on coal, with 78% of the current installed capacity coming from coal power in 2022, compared to 9.3% for solar and wind energy. [ABSTRACT FROM AUTHOR]

The current study proposes a model of autonomous Hydrogen Refuelling Stations (HRFS) installed on different sites in twenty French cities powered by renewable clean energy sources. The station is fully powered by photovoltaic (PV) panels, wind turbines with battery storage and involving an electrolyzer and hydrogen tank for producing and storing hydrogen. Using Homer simulation, three scenarios are investigated to propose an optimized model, namely Scenario 1 containing (PV-Wind-Battery) system, Scenario 2 with (Wind-Battery) technologies and Scenario 3 with (PVBattery) components. The otimization process executed demonstrates very competitive levelized cost of energy (LCOE) and levelized cost of hydrogen (LCOH) especially for the third scenario solely based on PV power with LCOE in range $0.354-0.435/kWh and a LCOH varying within $13.5-16.5/kg, for all 20 cities. An average net present cost (NPC) value of $ 1,561,429 and $ 2,522,727 are predicted for the first and second architectures while least net present cost of $1,038,117 is estimated for the third combination solely based on solar power according to all sites considered. For instance, minimum values are obtained for Marseille city with LCOE=$ 0.354/kWh and a LCOH=$ 13.5/kg in conformity with the minimum obtained value of NPC value of $886,464 with respect to the winner third scenario. In addition, more costly hydrogen production is expected for Grenoble city especially for scenario 1 and 2 where wind turbine technology is introduced. On another hand, thorough analysis of PV/wind hydrogen techno-economic operation is provided including improvements recommendations, scenarios comparison and environmental impact discussion. [ABSTRACT FROM AUTHOR]

The escalating demand for electrical energy in both rural and urban sectors necessitates a reliable and sustainable source, as the availability of traditional fossil fuels diminishes and their contribution to global warming becomes increasingly untenable. This study thus explores an environmentally-friendly solution via the Hybrid Renewable Energy System (HRES), a convergence of multiple renewable energy sources for electricity production. The focus is on an off-grid photovoltaic-wind turbine hybrid system that harnesses solar and wind energy to meet the electrical needs of the scarcely accessible Maluku Province. A feasibility analysis is conducted using the Homer software to evaluate the system's potential. The results reveal that Tual City, with the lowest Net Present Cost (NPC) amounting to Rp. 268,439,300.00 and a Cost of Energy (COE) of Rp. 3,220.56, presents the most promising potential for development. The total electricity generated by this hybrid system is projected to reach 9,457 kWh/year, highlighting its potential as a sustainable solution to the pressing energy needs in remote regions. [ABSTRACT FROM AUTHOR]

The Nigerian Universities rely on weak and unreliable fossil-based electric grids with diesel engine generators (DEG) as a backup. However, there is a potential to light up the campuses using power systems derived from primary renewable power systems (RPS) like wind turbine (WT) and solar photovoltaic (PV), that can be on or off-grid to improve the energy mix and duration reliably. This study presents the comparative analysis of the optimal hybrid grid and off-grid systems (OGS & OOGS) for serving the demand load of university buildings in four climatic regions of Nigeria. HOMER Pro is used to design and select the systems based on minimal net present cost (NPC) and cost of electricity (COE). The impact of a minimal renewable fraction of 95% on the optimal system architecture (OSA) and COE is studied for both grid and off-grid modes. Also, sensitivity analysis of the impact of key variables on performance for the sites is carried out. It is found that the OGS in the four regions is PV/Converter (Conv), while for the OOGS, it is PV/WT/DEG/battery (BB)/Conv except in Port Harcourt (PH), where it is PV/DEG/BB/Conv. The COE for the OGS in the Savana and monsoon climes of Enugu and PH are 10 and 19% more than that in the warm-semi arid climate zones of Maiduguri and Kano, which is approximately 0.09 $/kWh. The COE ($/kWh) for the OOGS is 0.21 in Maiduguri, 0.245 in Kano, 0.275 in Enugu and 0.338 in PH. An obligatory 95% RF changes the architecture and increases COE in all the locations except Maiduguri, with a slightly improved COE but higher NPC like other locations. It is established that the suggested hybrid system is beneficial and feasible for supplying more reliable and clean energy to educational buildings in different Nigerian locations.

As in many European countries, Turkey's foreign energy dependency is quite high. Reducing foreign dependency on energy on a national basis is possible by developing efficient systems and increasing the use of renewable energy systems. This study is created with the idea of combining these two principles. Ground source heat pump systems are widely used for cooling and heating residences due to their higher energy efficiency than ordinary air conditioners. On the other hand, it is possible to support these systems with other renewable energy sources. However, the cost is the most crucial factor for the end user. In this study, a techno-economic analysis of the support of the ground source heat pump system with off-grid hybrid (photovoltaic–wind–diesel) systems, in which renewable energy is included, was carried out. The energy consumption values of the ground source heat pump were simulated annually with the help of the eQUEST program. They were determined as 1988.1 kWh and 1715.9 kWh for heating and cooling, respectively. Seven different power systems were created and optimized using the hybrid optimization model for electric renewable software to meet the electrical energy consumption values obtained. The study results show that the optimum power system to meet the electricity consumption of the designed ground source heat pump is a hybrid system consisting of a 6.9 kW of PV, 4.5 kW of diesel generator, and 10 kWh of battery. In this configuration, the renewable fraction is 84%, and there is no unmet load. For the optimum power system, the levelized cost of electricity and levelized cost of heat values are 0.20 $ kWh−1 and 0.12 $ kWh−1, respectively. The results show that hybrid renewable energy-supported power generation systems are cost-effective for ground source heat pumps in remote areas. [ABSTRACT FROM AUTHOR]

In the modern world, as the population rises and fossil fuel supplies decline, energy demands continue to rise. Moreover, the use of fossil fuels harms the ecology, contributing to pollution and global warming. In order to overcome these difficulties, several approaches are revealed, such as the utilization of biomass as a renewable source of energy. Studies revealed that biomass can be converted into bioenergy via several thermal conversion processes, like pyrolysis, gasification, and torrefaction. Pyrolysis is the most convenient process to obtain three different types of biofuels (biochar as a solid, bio-oil as a liquid, and syngas as a gas). The biofuels produced in this process are normally lower in quality and cannot be used directly as fuel because they contain many undesirable components. Catalytic pyrolysis is one of the best processes to upgrade the quality of biofuels. Several varieties of catalysts are used in the catalytic pyrolysis process (ex situ and in situ). Due to stable operating conditions, both catalytic and non-catalytic pyrolysis procedures produce biochar that has a consistent output. Meanwhile, the effects of catalysts in the catalytic pyrolysis process considerably enhance the quality and quantity of bio-oils and syngas. By removing the unwanted oxygenated and nitrogenous components, the bio-oils produced through the catalytic pyrolysis method have a higher calorific value, reduced viscosity, and improved stability. Many researchers have looked at ways to increase the rate of pyrolysis, whereas a few have focused on maximizing the effects of the factors in order to improve the efficiency of catalytic pyrolysis. This review addresses the impact of catalysts on the catalytic pyrolysis of biomass to enhance the quality of the bio-oils in great detail. Machine learning and techno-economic analysis were investigated, as well as the future potential of the catalytic pyrolysis method for the generation of bio-oil. [ABSTRACT FROM AUTHOR]

The Indian Point Energy Center (IPEC) supplied approximately 25% of New York City and the surrounding area's electricity. As of April 2021, the nuclear power plant has been shut down, creating the need for other energy sources to meet the demand. This scoping analysis study examined the ability of different renewable pathways (solar photovoltaic (PV), willow biomass, onshore wind, and two combinations of these) to replicate the IPEC's electricity generation profile. Five renewable electricity generation supply profiles were developed and analyzed from monthly and seasonal perspectives. The timing and alignment of the different generation supply profiles relative to that of IPEC were analyzed. Productivity in MWh hectare−1 year−1 and economic feasibility of the renewable electricity pathway scenarios were assessed. This study identified the solar PV pathway as the most efficient in terms of electricity land productivity at 731.9 MWh hectare−1 year−1, while the willow biomass pathway was the least efficient at 15.2 MWh hectare−1 year−1. However, in terms of net electricity output to the grid, the solar PV pathway was the least productive at 137,610 MWh/year, while the onshore wind with willow biomass pathway produced the highest net output at 894,801 MWh/year. These findings are important at a time when policymakers are considering or implementing plans to phase out nuclear power in favor of renewable electricity. [ABSTRACT FROM AUTHOR]

Biomass is the most versatile feedstock for renewable energy and chemical production. Biochemical techniques such as fermentation and biomethanation have been developed extensively for converting biomass into bioethanol, biogas, and high‐value platform chemicals. However, the techno‐economic feasibility of the various biochemical techniques for the production of a range of biofuels and chemicals has not been fully consolidated in a review. This paper reviews the techno‐economic studies of biochemical conversion of biomass in a comparative fashion between feedstocks, treatment methods, and product types. The review starts with an overview of various biomass treatment approaches and the need for pre‐treatment for processing second‐generation feedstocks. This is followed by a review of the main biochemical conversion processes, offering insights into process stages, product yields and quality, as well as commercialization prospects and challenges. The various techno‐economic aspects of biomass conversion via biochemical techniques, such as conversion efficiency, production capacity, minimum selling price, capital cost, unit production cost, and profitability metrics, are critically reviewed. It was found that bioethanol and biogas are the most commercially viable products from the biochemical processing of biomass. The production of other biofuels and chemicals such as biobutanol, biohydrogen, furfural, volatile fatty acids, succinate, levulinic acid, and sugar alcohols via biochemical techniques is still largely limited by low conversion, frail microbial strains, cost of enzymes, and separation, and refining challenges. Overcoming these technical bottlenecks, and addressing the issues of feedstock price and supply security, are crucial for enhancing the overall techno‐economic attractiveness of biochemical processes for fuels and chemical production from biomass resources. © 2023 Society of Industrial Chemistry and John Wiley & Sons Ltd. [ABSTRACT FROM AUTHOR]

Green energy commodities are expected to be central in decarbonising the global energy system. Such green energy commodities could be hydrogen or other hydrogen-based energy commodities produced from renewable energy sources (RES) such as solar or wind energy. We quantify the production cost and potentials of hydrogen and hydrogen-based energy commodities ammonia, methane, methanol, gasoline, diesel and kerosene in 113 countries. Moreover, we evaluate total supply costs to Germany, considering both pipeline-based and maritime transport. We determine production costs by optimising the investment and operation of commodity production from dedicated RES based on country-level RES potentials and country-specific weighted average costs of capital. Analysing the geographic distribution of production and supply costs, we find that production costs dominate the supply cost composition for liquid or easily liquefiable commodities, while transport costs dominate for gaseous commodities. In the case of Germany, importing green ammonia could be more cost-efficient than domestic production from locally produced or imported hydrogen. Green ammonia could be supplied to Germany from many regions worldwide at below the cost of domestic production, with costs ranging from 624 to 874 $/t NH 3 and Norway being the cheapest supplier. Ammonia production using imported hydrogen from Spain could be cost-effective if a pan-European hydrogen pipeline grid based on repurposed natural gas pipelines exists. • Comprehensive database for global production and supply costs with projections until 2050. • Production costs are the significant cost component for liquid or easily liquefiable energy commodities. • Green hydrogen might be traded regionally via pipeline rather than shipped globally via LH 2. • Importing green ammonia is more cost-efficient than importing green hydrogen for domestic ammonia production in Germany. • Germany: Only if a low-cost European H 2 pipeline grid exists could ammonia production from imported H 2 be cost-effective. [ABSTRACT FROM AUTHOR]

Excessive use of fossil fuels has accelerated climate change and global warming necessitates the need for renewable energy sources that have a lower environmental impact. In the recent decade, lignocellulosic biomass has become a prominent alternative to renewable energy resources for the production of bioenergy. The pretreatment procedure is considered a pivotal step for transforming biomass into value-added products such as sugars, biofuels, etc. Therefore, the present work aims to study the effect of different pretreatment approaches on rice husk with acids (H2SO4 and HCl), alkalis (NaOH and KOH), and organic solvents (ethanol and methanol) utilizing different concentrations like (2, 4 and 6% in case of acids), (2,4 and 6% for alkalis) and (50% and 70% for organic solvents) with different residence time (1, 3, 6, and 24 h). The most effective results obtained from the aforementioned steps were further adopted for enzymatic hydrolysis. Further, the changes in structural properties of biomass were assessed in relation to the pretreatment process employing scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier Transform Infrared (FTIR) analyses. This paper also highlights the techno-economic analysis of alkali pretreatment. Additionally, the operational targets for the process were identified by using a modeling software-SuperPro Designer. Results obtained from the study showed a maximum yield of reducing sugar i.e., 1.906 ± 0.2 mg/ml (4% NaOH with 6 h of incubation). This study demonstrates that 4% NaOH pretreatment effectively disintegrates the biomass and yields high sugar recovery which can be used further for the production of biofuels and value-added products [ABSTRACT FROM AUTHOR]

The multi-renewable energy complementary system (MRECS) is a good plan that can effectively support the accomplishment of carbon peaking and carbon neutrality on schedule and take full advantage of renewable resources in rural areas. This research investigates the techno-economic feasibility of MRECS in rural areas to promote its large-scale implementation. A MRECS with integrated solar, wind, and biomass energy is proposed for a rural economic development zone. First, a scientific evaluation of the potential for renewable resources in rural areas is done. Second, a case study of the Jize Economic Development Zone is applied to examine the optimal MRECS configuration. Finally, an economic evaluation model that takes environmental benefits into account was created based on life cycle costs (LCCs). For the techno-economic analysis, the net present value (NPV), dynamic investment payback period, and internal rate of return (IRR) are also employed. Findings reveal that (1) the Jize Economic Development Zone has considerable development potential due to its abundance of renewable energy resources and ability to plan for 168.42 MW of renewable energy units; (2) to meet the demand for continuous power generation and realize the sensible use of renewable energy, a combination of 10 MW photovoltaic power generation (PV), 25 MW wind power generation (WT), 2 MW biogas power generation (BG), and 1 MW straw direct combustion power generation (SDC) is able to be implemented; (3) the provided renewable energy system can save indirect expenses up to 10.60 million RMB/year, with significant environmental advantages, when compared to grid extension; and (4) the NPV of the dynamic investment reaches RMB 322.44 million after accounting for the environmental advantages in the income of MRECS. The dynamic investment payback period is 6.42 years, and the IRR is 21.44%. According to the findings, the MRECS is economically viable, and capitalizing on the environmental advantages can increase those advantages even more. [ABSTRACT FROM AUTHOR]

Globally, nations are trying to address environmental issues such as global warming and climate change, along with the burden of declining fossil fuel reserves. Furthermore, countries aim to reach zero carbon emissions within the existing and rising global energy crisis. Therefore, bio-based alternative sustainable feedstocks are being explored for producing bioenergy. One such renewable energy resource is microalgae; these are photosynthetic microorganisms that grow on non-arable land, in extreme climatic conditions, and have the ability to thrive even in sea and wastewater. Microalgae have high photosynthetic efficiencies and biomass productivity compared to other terrestrial plants. Whole microalgae biomass or their extracted metabolites can be converted to various biofuels such as bioethanol, biodiesel, biocrude oil, pyrolytic bio-oil, biomethane, biohydrogen, and bio jet fuel. However, several challenges still exist before faster and broader commercial application of microalgae as a sustainable bioenergy feedstock for biofuel production. Selection of appropriate microalgal strains, development of biomass pre-concentrating techniques, and utilization of wet microalgal biomass for biofuel production, coupled with an integrated biorefinery approach for producing value-added products, could improve the environmental sustainability and economic viability of microalgal biofuel. This article will review the current status of research on microalgal biofuels and their future perspective. [ABSTRACT FROM AUTHOR]

Bio-gasoline derived from biomass is a clean and renewable energy, which can replace conventional petroleum-derived transport fuels. Here, we developed and evaluated a new catalytic process for the production of a renewable bio-gasoline from corn stover. In this process, corn stover is converted into bio-gasoline via a four-step catalytic conversion: hydrolysis of corn stover to levulinic acid (LA), dehydration of LA to angelica lactone (AL), di-/trimerization of AL to AL dimer and trimer and hydrogenation of AL dimer and trimer to bio-gasoline. Techno-economic analysis of a plant with a production capacity of 10,000 t/yr bio-gasoline was performed based on the integrated bio-gasoline production process using corn stover as feedstock. The results indicated that the price of target product as well as raw materials had great influence on this process. The return on investment of this process was estimated to be 15.8%, which maintained a break-even point when this process was operating at only 39% of the designed capacity. The results demonstrated that this technology provided an economically attractive and sustainable pathway in the conversion of waste biomass to bio-gasoline. Schematic of the integrated process for the bio-alkanes production from corn stover [ABSTRACT FROM AUTHOR]

Nowadays, with the need for clean and sustainable energy at its historical peak, new equipment, strategies, and methods have to be developed to reduce environmental pollution. Drastic steps and measures have already been taken on a global scale. Renewable energy sources (RESs) are being installed with a growing rhythm in the power grids. Such installations and operations in power systems must also be economically viable over time to attract more investors, thus creating a cycle where green energy, e.g., green hydrogen production will be both environmentally friendly and economically beneficial. This work presents a management method for assessing wind–solar–hydrogen (H2) energy systems. To optimize component sizing and calculate the cost of the produced H2, the basic procedure of the whole management method includes chronological simulations and economic calculations. The proposed system consists of a wind turbine (WT), a photovoltaic (PV) unit, an electrolyzer, a compressor, a storage tank, a fuel cell (FC), and various power converters. The paper presents a case study of green hydrogen production on Sifnos Island in Greece through RES, together with a scenario where hydrogen vehicle consumption and RES production are higher during the summer months. Hydrogen stations represent H2 demand. The proposed system is connected to the main power grid of the island to cover the load demand if the RES cannot do this. This study also includes a cost analysis due to the high investment costs. The levelized cost of energy (LCOE) and the cost of the produced H2 are calculated, and some future simulations correlated with the main costs of the components of the proposed system are pointed out. The MATLAB language is used for all simulations.

Abstract Cost-effective CO2 capture is essential for decarbonized cement production since it is one of the largest CO2 emission sources, where 60% of direct emissions are from CaCO3 decomposition and 40% are from fuel combustion. This work presents a low-carbon cement manufacturing process by integrating it with renewable energy for electric heating and thermal storage to replace the burning of fossil fuels in the conventional calciner. The low-carbon renewable energy reduces the indirect CO2 emissions from electricity consumption. The high-temperature CO2 is employed as the heat transfer fluid between the energy storage system and the calciner. In the proposed basic manufacturing process, the CO2 from the CaCO3 decomposition can be directly collected without energy-consuming separation since no impurities are introduced. Furthermore, the remaining CO2 from fuel combustion in the kiln can be captured through monoethanolamine (MEA) absorption using waste heat. In the two situations, the overall CO2 emissions can be reduced by 69.7% and 83.1%, respectively, including the indirect emissions of electricity consumption. The economic performance of different energy storage materials is investigated for materials selection. The proposed manufacturing process with a few high-temperature energy storage materials (BaCO3/BaO, SrCO3/SrO, Si, etc.) offers a higher CO2 emission reduction and lower cost than alternative carbon capture routes, i.e., oxyfuel. The cost of CO2 avoided as low as 39.27 $/t can be achieved by thermochemical energy storage with BaCO3/BaO at 1300 °C, which is superior to all alternative technologies evaluated in recent studies.

Highlights ∙ Review of evaluation methods for energy storage identifies need for new approaches. ∙ Formulation of new ‘market-potential method’ to identify value of storage. ∙ Pitfalls of cost approaches are identified in an European electricity system. ∙ Increasing storage design-freedom impacts technology value and system benefit. ∙ The ‘market-potential-method’ is useful for research and industry.

Essential oils are natural volatiles extracted using steam. Steam generation is an energy-intensive process and is invariably based on fossil fuels, briquettes or biomass. Based on the volumes of essential oil extracted, it can be considered as significant contributor to greenhouse gases. Though a lot of work is reported on essential oil extraction and characterisation, method for quantification of exact steam requirement and means for achieving it through sustainable source is not much reported.Through this study, steam requirement of 750 g/ml of Betel leaf volatile oil extracted and quantification of energy requirements for the extraction process is determined. For adoption of sustainable and clean energy source, opto-geometric optimisation and concentrating solar collectors (CSC) area calculation are carried out. The design of three CSC, namely, Linear Fresnel Reflector (LFR), parabolic dish collector (PDC) and parabolic trough collector (PTC), resulted in 78 m2, 122 m2 and 138.87 m2 of area to meet the steam requirement of the process.Adoption of CSC technologies for steam generation and replacing the prevalent technology needs detailed analysis and techno-economic comparison. This paper also focuses on cost-benefit analysis, taking into account CAPEX, OPEX, life-span, return on investment, levelized energy (steam) cost and the profitability index of net present value, payback period and internal rate of returns to check the economic feasibility of renewable energy. Analysis indicates that the cost associated with unit steam generation through CSC over the specified period is lower than a briquette-based steam generation. On adopting this sustainable technology for betel leaf oil extraction, even if the initial cost seems to be high, the payback period of LFR and PTC are 1.10 and 2.45 years, respectively. Based on this study, CSCs can provide a sustainable green solution for the extraction of essential oils.

Bangladesh is blessed with abundant solar resources. Solar power is considered the most desirable energy source to mitigate the high energy demand of this densely populated country. Although various articles deal with solar energy applications in Bangladesh, no detailed review can be found in the literature. Therefore, in this study, we report on the current scenario of renewable energy in Bangladesh and the most significant potential of solar energy's contribution among multiple renewable energy resources in mitigating energy demand. One main objective of this analysis was to outline the overall view of solar energy applications in Bangladesh to date, as well as the ongoing development of such projects. The technical and theoretical solar energy potential and the technologies available to harvest solar energy were also investigated. A detailed techno-economic design of solar power applications for the garment industry was also simulated to determine the potential of solar energy for this specific scenario. Additionally, renewable energy policies applied in Bangladesh to date are discussed comprehensively, with an emphasis on various ongoing projects undertaken by the government. Moreover, we elaborate global insight into solar power applications and compare Bangladesh's current solar power scenario with that of other regions worldwide. Furthermore, the potential of artificial intelligence to accelerate solar energy enhancement is delineated comprehensively. Therefore, in this study, we determined the national scenarios of solar power implementation in Bangladesh and projected the most promising approaches for large-scale solar energy applications using artificial intelligence approaches. [ABSTRACT FROM AUTHOR]

Renewable energy solutions are appropriate for on-grid and off-grid applications, acting as a supporter for the utility network or rural locations without the need to develop or extend costly and difficult grid infrastructure. As a result, hybrid renewable energy sources have become a popular option for grid-connected or standalone systems. This paper examines hybrid renewable energy power production systems with a focus on energy sustainability, reliability due to irregularities, techno-economic feasibility, and being environmentally friendly. In attaining a reliable, clean, and cost-effective system, sizing optimal hybrid renewable energy sources (HRES) is a crucial challenge. The presenters went further to outline the best sizing approach that can be used in HRES, taking into consideration the key components, parameters, methods, and data. Moreover, the goal functions, constraints from design, system components, optimization software tools, and meta-heuristic algorithm methodologies were highlighted for the available studies in this timely synopsis of the state of the art. Additionally, current issues resulting from scaling HRES were also identified and discussed. The latest trends and advances in planning problems were thoroughly addressed. Finally, this paper provides suggestions for further research into the appropriate component sizing in HRES. [ABSTRACT FROM AUTHOR]

An off-grid hybrid PV-wind-diesel-battery system with the best hybrid combination of system's components is designed to fulfill the electricity demand an off-grid village. For this purpose, five scenarios of system's renewable energy fractions (namely 0% renewable energy, 25% renewable energy, 50% renewable energy, 75% renewable energy and 100% renewable energy) were modeled, simulated, optimized and analyzed. The results obtained using the Hybrid Optimization of Multiple Energy Resources (HOMER) software of the National Renewable Energy Laboratory (NREL)/USA showed that the hybrid system with 50% renewable energy fraction is the optimal one in terms of both its technical performance and the cost of generated electricity which was found to be $0.202/kWh. It was also proved that deploying this system for electricity generation reduces the emissions by 49% compared to the conventional system comprising only diesel generator sets. Moreover, a sensitivity analysis was conducted to reveal the impact of diesel prices, solar radiation and wind speed on the cost of generated – by this optimal system – electricity. The obtained results indicated that diesel price is the most influential factor in the cost of generated electricity. It changes from $0.168/kWh to $0.0.237/kWh for a variation in diesel prices from −30% to +30% of its current prices. The effect of battery bank's storage capacity on the performance and cost of electricity, generated by the optimal system was investigated as well. The results showed that varying the storage capacity from −30% to +30% (from the base case value of 2971 kWh) increases the hybrid system's capital cost, but reduces each of the excess electricity, diesel generators operation hours, the annual diesel consumption and consequently the CO2 emissions. However, increasing the storage capacity from −30% till 0% (the base case), reduces the cost of electricity, while increasing the storage capacity from the base case of 0% to +30% does not affect the cost of generated electricity. [ABSTRACT FROM AUTHOR]

Low- and middle-income countries have tremendous potential for renewable energy production, including production of renewable carbon from locally prolific crops. In this work, bamboo endemic to West Africa (Bambusa vulgaris) was studied as a feedstock for the production of renewable sugars as the gateway to the local production of biofuels and bio-based chemical products. The effectiveness of delignification and amorphization pretreatments was evaluated, with the observation that quantitative (97 ± 4%) sugar yields could be obtained with a rapid initial hydrolysis rate (82 ± 4 mg g−1 h−1) but only when amorphization was performed following delignification. Experimental measurements and further characterization using 13C solid state nuclear magnetic resonance (NMR) helped establish the importance of amorphization and delignification and explained why the order of these treatments determined their effectiveness. The economics of the bamboo-based process were compared with those projected for corn stover, selected as a well-studied benchmark crop. Because of the higher bamboo growth rate compared with corn stover and the effectiveness of the pretreatment, the projected net present value (NPV) of the bamboo biorefinery was positive ($190 MM, U.S.), whereas the corn biorefinery projected to negative NPV (−$430 MM, U.S.). A socially sustainable framework for deployment of a bamboo biorefinery in a low- or middle-income economy was then proposed, guided by the principle of local ownership and stakeholder buy-in. The findings presented here motivate further investment in development of bamboo cultivation and conversion to sugars as a rapid route to decarbonization of low- and middle-income economies. [ABSTRACT FROM AUTHOR]

The utilization of renewable energy has the potential to alleviate global warming, reduce carbon emissions in the environment, and offer sustainable energy solutions to remote regions. Presently, 13 % of the worldwide population resides in isolated inland and coastal areas where electricity remains inaccessible. Consequently, implementing microgrids powered by renewable energy sources becomes essential to enhance electricity accessibility in these remote locations. This study aims to identify efficient and cost-effective renewable energy technologies suitable for deployment inland and coastal areas. The techno-economic feasibility of renewable energy systems is being evaluated in two distinct locations: Yadavole (inland) and Uppada (coastal) villages in the Indian state of Andhra Pradesh. The energy analysis encompasses various sources, including photovoltaic, diesel generators, wind turbines, flywheels, and batteries (Li-ion and lead-acid). The HOMER software conducts all necessary modeling and simulations for economic analysis and optimal system sizing. According to the simulation results, the most viable microgrid configurations for the inland region, Yadavole, are photovoltaic/diesel and generator/Li-ion. In contrast, for the coastal region, Uppada, photovoltaic/diesel, and generator/lead-acid configurations prove to be the most promising configurations. Moreover, a MATLAB model of the proposed system is created to analyze energy quality. Given the superior performance of Li-ion batteries in elevated temperatures typically found inland, this study recommends a diversified range of battery solutions. Specifically, Li-ion batteries are recommended for inland areas, while lead-acid batteries are recommended for coastal regions. This approach aims to efficiently store renewable power by the specific climatic conditions of each area. It is crucial to systematically analyze region-specific renewable energy technologies to provide valuable insight to stakeholders involved in investment and energy policy decisions. • Optimizing coastal and inland microgrids with PV/WT/DG/Li-ion/Flywheel/LA batteries. • Evaluate microgrids with real load profiles, resource data, and component prices. • Attain optimal component sizes based on the system's LCOE and NPC. • Optimal setups are PV/DG/Li-ion for Inland & PV/DG/LA for Coastal regions. • MATLAB model analyses & evaluates microgrid effectiveness in diverse scenarios. [ABSTRACT FROM AUTHOR]

• The hydrogen supply chain is modeled as a competitive multi-agent system. • Hydrogen policy planners, wholesale markets, distribution systems, and refueling stations are considered. • A hierarchical deep multi-agent reinforcement learning technique has been developed for Nash equilibrium. • Sensitivity analysis with profit margin, carbon credit, and green hydrogen supply limit are performed. • Carbon credits reduce CO₂ emissions predominantly with an active supply of green hydrogen. Hydrogen supply chain (HSC) consists of various production, conditioning, transportation, storage, and distribution processes, all of which require extensive computational resources for precise modelling. In this context, artificial intelligence (AI) is emerging as a pivotal tool for addressing model-based decision-making challenges, courtesy of its rapid and efficient computational capabilities. This paper proposes a comprehensive HSC model consisting of an economic policy planner, a wholesale hydrogen market, a power supply system, a hydrogen distribution system (HDS), and hydrogen refueling stations (HRSs). It leverages an AI circular hydrogen economist approach based on a hierarchical deep multi-agent reinforcement learning (MARL) algorithm, offering a new alternative to traditional multi-objective bi-level optimization platforms. The model incorporates green, blue, and gray hydrogen production processes as viable hydrogen production pathways, with the hierarchical MARL's agents representing the HDS and HRSs at two decision-making levels. Energy requirements are met through a combination of on-site renewable energy sources, the main power grid, or distributed power generation systems. Several HSC scenarios are examined with respect to various combinations of green hydrogen supply rates and carbon credits granted to them under optimum conditions. The results showed that the developed hierarchical MARL has the potential to replace mathematical programming (MP), uncovering a new economic-environmental trade-off between profit of HDS and operational costs of HRSs. Notably, green hydrogen transactions exponentially increase within the supply chain as the carbon credits exceed $1 per kilogram of hydrogen. While this research focuses on optimizing daily operations within the HSC, future efforts can aim to extend this optimization to forecasted annual operations. [ABSTRACT FROM AUTHOR]

[Display omitted] • Intensification of biogas to fuels process aids to break economy-of-scale barrier. • Reforming and synthesis at the same pressure avoids compression of syngas. • Process evaluated in 4 scenarios via design and TEA based on lab data. • Scenario with recycling resulted in lowest minimum fuel selling price of $4.59/gal. • >11.7 % diesel yield from biogas mass required to surpass conventional method. The Intensified Biogas to Liquid (IBGTL) process aims to overcome traditional economy-of-scale barriers in biogas-to-liquid fuel production by integrating bi-reforming and Fischer-Tropsch synthesis (FTS) in a single IBGTL reactor. This reactor operates at uniform pressure with different optimized temperatures across two zones for efficient conversion, utilizing multifunctional bi-reforming catalysts and high-temperature FTS catalysts. Bench scale experiments were carried out using landfill gas (LFG) in a single pass process, and the yield data from these experiments were fed into process scale-up design and techno-economic analysis (TEA) across four scenarios: (1) a single pass process, (2) a process with material recycling, (3) a process with liquefied petroleum gas (LPG) co-product recovery, and (4) a process with electricity generation from the fuel gas produced. TEA identified Scenario 2 as the most cost-effective, achieving a Minimum Fuel Selling Price (MFSP) of $4.59 per gallon, competitive with the current national diesel price of $4.7 per gallon. However, comparison with the conventional two-reactor system highlights the need for catalyst performance improvements. Sensitivity analysis emphasized the importance of manufacturing cost, liquid fuel yield, and biogas flow rate. Further analysis determined that the IBGTL process must achieve a diesel mass yield beyond 11.7% to surpass the economic viability of the conventional TriFTS (Tri-reforming followed by Fischer-Tropsch Synthesis) process. If the IBGTL process attains the TriFTS yield of up to 17%, the resulting MFSP could be approximately 31% lower than the current TriFTS MFSP. Renewable energy credits and carbon credits can further enhance the economic viability of BGTL processes. [ABSTRACT FROM AUTHOR]

With the global shift to renewable energy sources to address environmental concerns, hydrogen has become a popular choice for energy transportation. The methane pyrolysis reaction is considered a promising technology for the future because it can produce hydrogen using only 13 % of the theoretical thermodynamic energy per 1 mole of H 2 needed for water electrolysis. Since methane pyrolysis operates at high temperatures above 1200 ℃ and produces byproducts such as solid carbon, research on high-performance catalysts and suitable reactor shapes is critical to commercialize the technology. This paper introduces the reaction mechanism of the methane pyrolysis reaction and summarizes available solid and liquid catalysts. In addition, existing reactor designs have been introduced, and the techno-economics based on the overall process design and operating conditions are analyzed. As a result, methane pyrolysis is proven to be a favorable way to produce clean hydrogen compared to other hydrogen production processes. • Advances in hydrogen production by methane pyrolysis have been reviewed. • Diverse catalysts and reactor types in the literature have been investigated. • From a techno-economic perspective, methane pyrolysis is a promising way to product clean hydrogen. [ABSTRACT FROM AUTHOR]