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The increasing adoption of electric vehicles (EVs) presents both opportunities and challenges for power networks. While EVs have the potential to reduce carbon emissions, accommodating their growing power demand requires careful planning to prevent overloading and mitigate environmental impacts. This paper introduces an integrated hosting capacity model to facilitate higher EV penetration while maintaining environmental standards. In addition to EV charging stations, the model incorporates transmission lines, reactive power compensators, energy storage systems, and thyristor-controlled series compensators to ensure a reliable power supply. The model aims to maximize EV charging station deployment, minimize greenhouse gas emissions, and optimize net present value through hosting capacity strategies. Three hosting capacity plans are proposed to analyze the impact of prioritizing one of these objectives over the others in network configurations. Accurate EV demand forecasting is critical for this model, and a swarm intelligence forecasting algorithm is proposed to explore various forecasting approaches. The model is complex and involves nonlinear multi-objective optimization. To solve it, a new hybrid optimization algorithm is introduced, combining the features of the Marine Predators Algorithm and the Honey Badger Algorithm. Three hybridization schemes—Series Hybrid Scheme, Population Division Scheme, and Switching Strategy Scheme—are developed to address the optimization challenges effectively. The results show that the first and second hybridization schemes are the most effective for solving the EV load forecasting models, with a robustness of at least 90%. In contrast, the robustness of the third scheme reaches only 30% in some models. Simulation studies on the IEEE 9-bus network and the IEEE 30-bus system validate the model's effectiveness in integrating EVs while achieving environmental sustainability objectives. The findings show the superiority of the proposed hybrid schemes in solving the hosting capacity model in terms of finding optimal solutions. However, the third scheme required less computing time than the others, with its convergence time being at least 33.3% shorter. [ABSTRACT FROM AUTHOR]

We investigate the use of various momentum methods in combination with an ensemble approximation of gradients, for accelerated optimization. Although momentum gradient descent methods are popular in machine learning, it is unclear how they perform when applied to time-consuming dynamic problems such as production optimization for petroleum reservoir management. Four different momentum methods are extensively tested on a reservoir test case in one deterministic and one robust setting. The numerical experiments show that momentum strategies yield, on average, a higher net present value with fewer simulations needed. [ABSTRACT FROM AUTHOR]

The problem of project portfolio selection considering risk propagation is a new research topic, but it overlooks the fact that the risk propagation process can be hindered by resource mobilization within candidate projects, which is defined as "risk absorption" in this paper. Neglecting this process may lead to the risk propagation process being overestimated, thereby resulting in the selection of suboptimal projects. Based on this, this article examines the risk absorption process in project portfolio selection problem, aiming to investigate its impact on project portfolio decision, ultimately resulting in the selection of more stable project portfolio. To address this issue, the article first examines the process of risk absorption among projects and calculates the amount of risk absorbed based on the strength of the interactions between the projects selected. Secondly, the total risk intensity of the project is given by calculating the risk propagation intensity and self-incurred risk intensity. Finally, a dual-objective project portfolio selection model considering risk absorption is developed by combining the risk intensity and net present value of the project. The analysis of a case study demonstrates that (1) considering risk absorption can reduce the probability of project risks occurring due to being propagated, (2) considering risk absorption will prioritize projects with higher returns, albeit accompanied by relatively higher risks. [ABSTRACT FROM AUTHOR]

Manufacturing industries are vital for economic development, but they cause significant environmental damages. As there are scarce research studies for this industrial sector from developing countries, this article reports a comprehensive environmental and economic analyses for cutlery manufacturing in Pakistan. SimaPro 9.5 was used as a modelling software tool, while ReCiPe 2016 methods were used to evaluate various midpoint and endpoint environmental impacts. Various economic indicators were used to evaluate the economic performance of different alternative scenarios. The results revealed that injection molding process, due to its energy-intensive nature caused the most environmental impacts as compared to other manufacturing processes. Global warming and terrestrial ecotoxicity were the most affected impact categories with values of 11.8 kg CO2 eq and 12.0 kg 1,4-DCB, respectively. Meanwhile, at endpoint level, human health category was most damaged as compared to others. Based on technical process intervention and energy transition, four different alternative scenarios were developed. In comparison with baseline scenario, the alternative scenario with double-cavity mold resulted in a reduction of more than 30% for various impact categories. The other three alternatives were grounded on the use of solar energy (50% or 100%) and injection mold with double or single cavity. Overall, the alternative scenario with 50% solar energy and double-cavity mold was the best solution that showed more than 50% reduction in most of the impact categories, less than 3-year payback time, 2.12 million (Pakistani Rupees) net present value, and 36.3% of return on investment. This study clearly shows the importance of renewable energy resources and simple changes in process technology for improving sustainability performance. The relevant stakeholders can effectively use the results and methodology of this study as a reference and guide for future research and practical interventions, especially in developing countries. [ABSTRACT FROM AUTHOR]

In post-conflict Colombia, the government has prioritized resettlement of displaced people through development of strong rural livelihoods and the sustainable use of natural capital. In this paper, we considered government proposals for expanding payment for ecosystem services (PES) and sustainable silvopastoral systems, and private-sector investment in habitat banking. We coupled the Integrated Economic-Environmental Model (IEEM) with spatially explicit land use and land cover change and ecosystem services models to assess the potential impacts of these programs through the lens of wealth and sustainable economic development. This innovative workflow integrates dynamic endogenous feedbacks between natural capital, ecosystem services and the economic system, and can be applied to other country contexts. Results show that PES and habitat banking programs are strong investment propositions (Net Present Value of US$4.4 and $4.9 billion, respectively), but only when moving beyond conventional economic analysis to include non-market ecosystem services. Where a portfolio investment approach is taken and PES is implemented with sustainable silvopastoral systems, investment returns would reach US$7.1 billion. This paper provides a detailed evaluation of the benefits of investing in rural livelihoods and enhancing Colombia's natural capital base, with empirical evidence to inform the spatial targeting of policies to maximize economic, environmental and social outcomes. [ABSTRACT FROM AUTHOR]

Oilfield development optimization plays a vital role in maximizing the potential of hydrocarbon reservoirs. Decision-making in this complex domain can rely on various objective functions, including net present value (NPV), expected monetary value (EMV), cumulative oil production (COP), cumulative gas production (CGP), cumulative water production (CWP), project costs, and risks. However, EMV is often the main function when optimization is performed under uncertainty. The behavior and performance of different objective functions has been investigated in this paper, when EMV is the primary criterion for optimization under reservoir and economic uncertainty. One of the goals of this study is to provide insights into the advantages and limitations of employing EMV as the sole objective function in oil field development decision-making. The designed optimization problem included sequential optimization of design variables including well positions, well quantity, well type, platform capacity, and internal control valve placements. A comparative analysis is presented, contrasting the outcomes obtained from optimizing the EMV-based objective function against traditional objective functions. The study underscores the importance of incorporating multiple objective functions alongside EMV to guide decision-making in oilfield development. Potential benefits in minimizing CGP and CWP are revealed, aiding in the mitigation of environmental impact and optimization of resource utilization. A strong correlation between EMV and COP is identified, highlighting EMV's role in improving COP and RF. [ABSTRACT FROM AUTHOR]

In Brazil, pre-salt carbonate reservoirs are largely responsible for the current increase in oil production. However, due to its peculiar characteristics, increasing oil recovery by water injection is not enough. Therefore, we seek to evaluate the recovery potential using chemical methods (cEOR). Among these, the Alkali Surfactant Foam (ASF) method appears with high potential, a variant of Alkali Surfactant Polymers (ASP) without the problems presented by it. Therefore, this work presents an innovative methodology, which seeks to evaluate the potential for recovery with ASF in carbonate reservoirs by integrating experimental characterization and recovery prediction using reservoir simulation. For this, phase behavior and adsorption analyses were carried out. The experimental results provided key parameters for the simulation, such as optimal salinity, surfactant adsorption, foam mobility reduction factors. The results are from two case studies of AS and ASF flooding, using a section of UNISIM-II benchmark, using a one-quarter of five-spot model. Having the modelling for these cEOR methods defined, an optimization process for each method was applied, allowing a reliable comparison among the methods and over a base case of water injection, seeking the maximization of the net present value (NPV). As a result, in the experimental part, a low interfacial tension (IFT) value of 0.003 mN/m was achieved with a surfactant adsorption reduction of 17.9% for an optimal setting among brine (NaCl), alkali (NaBO2.4H2O), and surfactant (BIO-TERGE AS 40). In the reservoir simulation part, using a fast genetic algorithm in the optimization process, a NPV of US$ 14.43 million higher than the base case (water injection) and a 4.5% increase in cumulative oil production for the ASF injection case were obtained. Considering the analyses of production curves (cumulative oil production and oil rate) and oil saturation maps, a considerable oil production anticipation was observed, which was the main reason for NPV improvement, proving the high potential for application of the ASF method in carbonate reservoirs. [ABSTRACT FROM AUTHOR]

Most regulatory jurisdictions now require financial assurance for mines for post-closure activities, which typically include long-term monitoring and maintenance, and most importantly post-closure water treatment. Critical choices in calculating post-closure financial assurance include using a reputable cost estimation model to establish the amount needed for reclamation, selecting a realistic net return-on-investment for post-closure trust funds, and choosing the period of time over which the net present value calculation of the financial assurance is based. A conservative estimate of the amount of financial assurance is warranted to protect the public from assuming these costs. However, some regulatory agencies use financial assurance estimate practices that are arbitrary. The data and procedures needed to analyze and recommend conservative net present value calculations are readily available, but in too many instances are not being utilized. [ABSTRACT FROM AUTHOR]

India is now one of the top five countries in the world for PV and solar thermal power generation. At the same time, we must develop a plan for recycling these massive numbers of solar panels in the future. This article has contributed to proposing the resulting regulatory system. The PV waste management sector is extremely neglected, leaving it entirely to the scrap trading underground. There is not enough of a system in place to collect and reuse the solar panels' components for recycling. In addition, a solid institution to manage this procedure on a commercial scale has yet to be established. As a result, the purpose of this work was to use cost–benefit analysis to determine the economic viability of a solar module recycling project in India. The benefit–cost ratio (BCR) and net present value (NPV) were calculated to be 1.64 and 25.22 million USD, respectively. According to the sensitivity study, the most delicate issues impacting the project's economy were the selling benefits of recycled materials and tax. Finally, this analysis offered strategies for the government and linked businesses to enhance the economy. [ABSTRACT FROM AUTHOR]

The valuation and planning of complex projects are becoming increasingly challenging with rising market uncertainty and the deregulation of many industries, which have also raised the need for efficient risk management. We take the perspective of a private firm interested in sequential capacity expansion of a project and develop a framework for measuring the downside risk of the serial project and optimising the sequence of the stages. Under general distributional assumptions for the duration of each stage, we present an accurate representation of the project's net present value (NPV) distribution based on a Pearson curve fit, leading to closed-form expressions for the associated risk measures. We then assess the impact of duration variability on the value at risk and demonstrate its role in stochastic project scheduling. We also account for the trade-off between maximising the expected NPV and minimising the risk exposure, and obtain the optimal schedule for risk-averse decision-makers. It becomes obvious that both the duration variability of each stage and the decision-makers' risk preferences can significantly affect the optimal sequence of the stages and that high duration variability is not always undesirable, even for risk-averse decision-makers. [ABSTRACT FROM AUTHOR]

Adoption of high-yielding, early maturing and drought-resistant varieties is a good adaptation strategy to cope with the adverse effects of climatic events like frequent occurrence of drought and heat stress. Kufri Pukhraj, an early bulking cultivar that is, drought tolerant and moderately resistant to late blight, is the most popular potato variety in India, covering 33% of total potato area. This paper assesses the gross returns from the investment in Kufri Pukhraj using the economic surplus method in a closed economy condition at all-India level. Time-series published data from various sources have been used in this study. A total of 41-year period (1978–2018) is considered to estimate the benefits in an ex-post framework using actual data. The analysis of varietal diversity of potato revealed that 11 out of 66 varieties are most popular and share about 75% of total potato area in India. These varieties are early-to-medium maturing and medium-to-high tolerant to drought. The findings show that R&D investment on Kufri Pukhraj has led to enormous benefits to both consumers and producers. The total surplus accrued to economy is estimated as Rs 540,840 million during 1978 to 2018. The net present value of returns was Rs 157,720 million and Rs 63,600 million at 5% and 8%, respectively. The study has found internal rates of return of 48%, which is a good rate of returns. Sensitivity analyses also showed good returns, with total economic surplus ranging from Rs 293,220 million to Rs 814,950 and internal rates of return ranging between 45 and 50%. Results imply that the investment in R&D of Kufri Pukhraj has proven to be successful and beneficial in India. The study recommends that other popular varieties equipped with other traits should be evaluated for shaping future research policies of potato. [ABSTRACT FROM AUTHOR]

Blue economy approach is slowly gaining significance, and many nations are placing it on their national agendas to strengthen the maritime policy. The sustainable exploitation of marine resources is the key to achieving blue economic development including commercial seaweed farming. The production of red seaweeds with superior-quality agar in India has propelled research to develop viable cultivation technologies. However, the carragenophyte Kappaphycus alvarezii has more industrial support and is the only seaweed taxa commercially farmed in India. The present investigation offers a comparative economic case study between these two groups. Critical economic parameters were analyzed for important operational components, i.e., individual-centric operation and family-centric operation, under three scenarios namely, without subsidy and 40% and 60% subsidy respectively. A lowest payback period was noticed for K. alvarezii cultivated by the family-centric operation under all three scenarios (without subsidy: 0.76 year; 40% subsidy: 0.61 year; 60% subsidy: 0.53 year). However, the minimum breakeven point in the range of 7.3–10.1 dry tons was reported in the case of farming of Gracilaria dura under different subsidies, followed by K. alvarezii (breakeven point value: 15.1–22 dry tons). The net present value and internal rates of return of K. alvarezii were found to be 3123–8863 USD and 31–90%, respectively under different subsidies. All four agarophytes resulted in negative net present values irrespective of subsidy scenario and hence, it is not economically viable. In terms of profit, among five seaweeds, K. alvarezii only showed a profit of 328–902 USD and 4905–10,646 USD for individual and family-centric models, respectively. The more comprehensive analysis with realistic costing—considering uncertain weather conditions and disease infestation—also pointed out the superiority of family-centric operations. The projections from economic analysis revealed that commercial farming of agarophyte is not viable at individual and family-centric operations, but K. alvarezii farming is viable for both operations in India. [ABSTRACT FROM AUTHOR]

2,3-Butanediol (BDO) is a crucial precursor in various industries, traditionally derived from fossil resources, raising environmental concerns. This study evaluates the techno-economic feasibility of producing BDO from wood residues, a sustainable resource abundantly available in Nordic countries. By modeling a biorefinery plant with a daily capacity of 100 metric tons of wood chips, three scenarios (Sc.) were explored: Sc. 1, where BDO is the sole product; Sc. 2, where BDO is produced alongside methane and biofertilizer; and Sc. 3, which incorporates a combined heat and power system using biogas from the waste stream. The analysis emphasizes the minimum selling price (MSP) of BDO, revealing it to be lowest in Sc. 1 at USD2.97/kg, compared to USD3.20/kg and USD3.48/kg for Sc. 2 and Sc. 3, respectively. Notably, sensitivity analysis highlighted the impact of processing capacity on economic performance, suggesting a potential for higher scalability and profitability in Sc. 2. This study contributes novel insights into the role of processing capacity and fermentation yield in optimizing BDO production, providing a valuable framework for technology developers aiming to establish wood-based biorefineries. These findings not only enhance understanding of economic thresholds but also underscore the importance of resource efficiency and strategic planning in bio-based production setups. Highlights: Economic viability of a biorefinery unit was assessed for 2,3-butanediol production. Facilities and utilities expenses were the main contributors to operating costs. Equipment and construction fees were the main contributors to total capital cost. For profitability, processing capacity should exceed 2.6-ton wood residues/h. Valorizing process waste streams increased both revenue and associated costs. [ABSTRACT FROM AUTHOR]

For Egypt, ethane is a vital chemical precursor, with the potential to significantly attract financial resources and drive economic growth. Enhancing its added value necessitates efficient recovery of ethane before it enters the national grid without processing. This research investigates the technical and economic feasibility of integrating natural gas liquids (NGLs) from three Egyptian NGLs plants—South Western Desert NGLs (SWD NGLs), North Western Desert NGLs (NWD NGLs), and East Mediterranean NGLs (EMD NGLs)—to improve ethane recovery from natural gas fields. The study focuses on revamping these NGLs plants using various NGLs recovery techniques, conducting a comprehensive comparison to identify the most effective methods for processing rich feed gas. Detailed design of the NGLs recovery processes was developed using HYSYS V.14 simulation software and supplementary calculation sheets. The design criteria encompass both technical and economic parameters to ensure a holistic approach in meeting project requirements. Results indicate a significant increase in ethane recovery: 16% for SWD NGLs, 10% for NWD NGLs (A, B, C), and 85% for EMD NGLs. This improvement will boost ethane feedstock for petrochemical companies from 2000 ton/day to 3500 ton/day, enabling increased polyethylene production. Economic analysis for the base case shows an expected internal rate of return (IRR) of 26%, a net present value (NPV) of USD 73 million, and a payback period of approximately 3 years. Sensitivity analysis on product prices, feed gas prices, and total capital investment confirms the project's economic viability, with all cases showing feasibility (IRR ≥ 15%) except when product prices fall below USD 225/ton for propane, USD 215/ton for liquefied petroleum gas (LPG), and USD 25/bbl for condensate. This study highlights the potential for enhanced ethane recovery, offering substantial economic benefits and supporting the growth of Egypt's petrochemical industry. [ABSTRACT FROM AUTHOR]

Agriculture is extremely vulnerable to climate change. Changes in precipitation and temperature patterns will result in long-term declines in production and short-term crop failures. These short- and long-run impacts are projected to be particularly severe in developing countries because of high exposure to climate change impacts and dependence on rain-fed agriculture. To overcome the challenges of a changing climate on agricultural production in West Africa, farmers implement a range of adaptation strategies. Using a systematic review of spatial–temporal empirical literature published on climate change adaptation in the West African ecological region and data collected from semi-structure interviews to farmers, we identified adaptation strategies in West Africa and explored their efficiency computing their cost–benefit ratio to examine farmers' private returns per dollar spent. Our results show that 91 adaptation strategies are employed by farmers in the sub-region, classified into six categories: cultural practices, forest management strategies, land management practices, water management strategies, risk management strategies and the use of improved technologies. Our results show that planting of trees, increased use of fertilizers, use of resistant varieties, mixed farming and crop diversification are the strategies that generate the highest returns, with highest annual mean net benefits. Mulching was also found a financial attractive as it generates the greatest returns per dollar spent ($3.2) and internal rate of return due to its low associated cost. The adaptation options that generate net mean annual losses were water harvesting, erosion control and making of big mounds. In a scenario with a 10% annual increase in annual benefits and costs over a period of five years, all the adaptation strategies, apart from water harvesting, will yield positive net present value benefits for the farmers. Since any climate change adaptation will inevitably have heterogenous financial implications to farmers, result from this study sheds light on farmers' private incentives to embark on adaptation strategies and provides information needed for decision support on adaptation measures choice selection, policy and planning across the sub region with relevance to other areas. [ABSTRACT FROM AUTHOR]

Agroforestry can address multiple environmental challenges across the agricultural sector, for example biodiversity loss and soil degradation. However, agroforestry uptake remains low in Germany. Since economic considerations are important for farmer uptake, this paper compares the economic performance of conventional arable farming with silvoarable alley cropping in Brandenburg. Using a modelling approach, the net present value (NPV) is calculated to assess the competitiveness of alley cropping with poplar compared to arable farming under different scenarios. These scenarios cover a range of crops, rotation schedules, alley widths, woodchip prices, and yield levels. Additionally, policy measures that can compensate for potential economic losses associated with transitioning to agroforestry are considered. Results show that short rotation alley cropping had higher NPVs than medium rotation alley cropping, mainly due to cash-flow characteristics. Short rotation alley cropping can be competitive at high woodchip prices without policy support, while at low or average prices alley cropping needs subsidies to be competitive. Medium rotation systems at all price levels were not competitive unless policy support was provided. Current policy payments were unable to make silvoarable alley cropping competitive except at high woodchip prices. When subsidies increase, alley cropping can be competitive even at low or average woodchip prices and over a range of site conditions. Besides policy support, economic performance was strongly influenced by woodchip prices, relative yield potential of poplar and arable crops, and site conditions. [ABSTRACT FROM AUTHOR]

Estimating the impact of economic policy uncertainty (EPU) on enterprise ambidextrous innovation can provide insight into firms' current innovation choice orientation, but few studies systematically reveal the relationship between the two. We have developed a new investment valuation construct that includes three parts: the direct net present value, growth option value, and strategic preemption value. Based on this, we systematically expound the relationship between EPU and enterprise ambidextrous innovation and explore the moderating effect of government subsidies and managerial ownership. Using the patent text mining data of Chinese A-share listed companies in Shanghai and Shenzhen from 2010 to 2019 and exploiting the world average temperature as an instrument for EPU, we find that EPU promotes enterprise's exploitative innovation and inhibits enterprise's exploratory innovation through the redistribution of R&D investment in ambidextrous innovation. Government subsidies negatively moderate the relationship between EPU and enterprise exploitative innovation, but have no moderating effect on the relationship between EPU and enterprise exploratory innovation. While managerial ownership positively moderates the relationship between EPU and enterprise exploitative innovation, no evidence of a moderating effect was found in the relationship between EPU and enterprise exploratory innovation. [ABSTRACT FROM AUTHOR]

In the coming decade, as restrictions on fossil fuel usage become more stringent, investment in renewable energy projects presents an increasingly appealing opportunity. Evaluating investment attractiveness involves considering both profitability and investment risk. This study proposes a multi-objective mathematical model for identifying the optimal Renewable Energy Project Portfolio (REPP), aiming to maximize net present value while minimizing investment risk. The key innovation of this model is its incorporation of project lifetime and workforce employment considerations to discern the best REPP. To optimize the objective functions of this mathematical model, a hybrid meta-heuristic algorithm combining Artificial Immune System (AIS) and Artificial Fish Swarm (AFS) algorithms is introduced. Genuine data from a varied spectrum of renewable energy projects spanning 20 countries has been meticulously collected. The proposed model is optimized using this dataset, considering portfolio sizes of 3, 5, 10, and 15. The numerical results indicate that, at a specific investment risk threshold, the proposed hybrid algorithm outperforms both AIS and AFS in terms of profitability. Furthermore, the assessment of the geographical distribution of selected projects reveals a deliberate effort to avoid concentration in any specific region, demonstrating a commitment to identifying optimal investment opportunities globally. This research advances the understanding of renewable energy project portfolio optimization, providing valuable insights for investors, policymakers, and sustainable development practitioners. [ABSTRACT FROM AUTHOR]

In this paper, the research and development project scheduling problem (RDPSP) under uncertain failure of activities is formulated where an activity's failure results in the project's overall failure. A scenario-based bi-objective model to maximize the expected net present value (eNPV) and to minimize the NPV's risk by conditional value-at-risk (CVaR) measurement is presented. For this purpose, different modes of failure or success of activities have been considered as a stochastic parameter by a set of scenarios. To formulate the problem, a nonlinear model is first presented, then a mixed-integer programming (MIP) model of the problem is developed by piecewise approximation. Some valid inequalities are presented to improve the performance of the MIP model. A sequential sampling procedure is also used to approximate the solution of the MIP model with a large number of scenarios. The experimental results have shown that the sequential sampling procedure attains high-quality solutions in a reasonable CPU time. [ABSTRACT FROM AUTHOR]

The proper solution to the optimal investment decision plays an important role in the decision-making process. Compared to the classical net present value rule, the real option approach captures the value of the flexibility embedded in the investment opportunity. In this paper we study relevant dynamic models interpreting the project as well as flexibility value as the option premium, namely investment projects from the mining industry. Specifically, the problem we face is described by systems of partial differential equations of the Black-Scholes type in terms of time and output price, equipped with the terminal condition enforced at time instants resulting from the specific timing and type of the flexibility that such an investment provides. As a result of that, the comprehensive methodological concept, based on the discontinuous Galerkin approach, is proposed to improve the numerical valuation process. The resulting numerical procedure is sufficiently robust to cope with an early exercise constraint as well as a wide range of model parameters. Finally, the performance of the solving procedure is accompanied within the conceptual case study arising from mining industry, supplemented by comments of practical importance. [ABSTRACT FROM AUTHOR]

Background: Fossil fuel utilization is the biggest contributor to the emissions of greenhouse gases which are the main reason for global warming. Solar energy photovoltaic (PV) technology is one of the most rapidly rising technologies and is a sturdy candidate to replace fossil fuels due to its versatility. Egypt receives high solar intensity which makes it a perfect place for utilizing this technology. However, for the past years, the focus in Egypt was on using solar energy for residential applications, henceforth a research gap was identified in studying the feasibility of using solar energy for industrial applications in Egypt. To ensure the sustainability of this application, this feasibility study addresses technical, economic, environmental, and social aspects. Results: A case study is investigated for utilizing solar PV panels for energy generation in Egypt at an industrial site. A food factory was studied under three scenarios. Scenario 1 is the baseline case for the other scenarios with fixed tilted PV panels and no storage, Scenario 2 is the same as Scenario 1 with difference in is the model of the PV panels with no tracking or storage system. Scenario 3 has a vertical axis tracking system. Software was used to simulate the performance of the three scenarios for 25 years. Results have shown that Scenario 1 and Scenario 2 had close values of the annual energy production. However, Scenario 3 produces 2047 MWh annually which is considerably higher. Finally, a sensitivity analysis is carried out to test the effect of some economic parameters on the financial feasibility. Conclusions: All the three scenarios are found to be feasible. Scenario 1 has the shortest discounted payback period with a net present value of 414,110.12 USD, a nominal levelized cost of energy of 0.022 USD/kWh, and avoided CO2 emissions of 14,898.993 tons. Although Scenario 3 has higher costs, it has higher energy production and better impact on the environment with 18,891.435 tons of avoided CO2 emissions. The paper concluded that a generalization could be done about using solar PV systems in Egypt for energy generation to be sustainable and feasible technically, economically, and environmentally. [ABSTRACT FROM AUTHOR]

Continuous natural gas flaring wastes significant energy resources and increases greenhouse gas emissions, contributing to global warming. Our work provides an overview of a technique to recover flare gas and reduce CO2 emissions to a minimum level. There are two methods to recover flare gas: the recovery of natural gas liquids and sales gas production by existing LPG unit and the production of liquid fuels by mini-GTL unit (gas to liquid). This study was conducted using real data from the field. All cases were simulated using Aspen HYSYS software. The mini-GTL unit is modeled using an autothermal reforming method. CO2 emissions will be reduced by 107.68 tonne/day in both methods. Economic analyses revealed that the NGL and sales gas product has a net present value (NPV) of 77.03 MMUSD, while the mini-GTL product has an NPV of 73.7 MMUSD. The study showed that we could extract natural gas liquids (NGLs), including propane, LPG, and sales gas, from the flare gas or convert it to liquid products, including gasoline and diesel. The expected internal rate of return (IRR) and payout time (POT) for NGL and sales gas method are 150.73% and 0.27 years, respectively. The mini-GTL method is recommended due to Egypt's petroleum fuel shortage and the best solution without an entry point to the Egyptian national gas grid in the plant. However, the IRR and POT for the mini-GTL method are 30.09% and 1.19 years, respectively, and it needs more CAPEX than the NGL and sales gas method. Highlights: • A model has been developed to recover stranded associated gas through a flare gas recovery system (FGRS). • Natural gas liquids are recovered in addition to sales gas production. • Mini-GTL unit (gas to liquid) is studied as an option for flare gas recovery. • Financial modeling parameters and what-if analysis techniques are reported. [ABSTRACT FROM AUTHOR]

This study proposed a spatially explicit non-linear function for estimating the benefits following the release and establishment of the koinobiont endoparasitoid, Fopius arisanus at a landscape scale in Kenya to control the oriental fruit fly, Bactrocera dorsalis. The proposed model relates the bioecology of the parasitoid to its impacts on fruit growers' economic benefits per fruit farm. In addition, we used financial information attributed to the cost of importation, conducting associated research, and the release of F. arisanus to estimate the return on investment from the parasitoid's release in Kenya. We observed distinct variations in potential annual benefits across the diverse mango cultivation regions throughout Kenya. In Kenya, the potential benefits range from negligible benefit to high benefit per acre (US$201- US$255) annually when classical biological control is applied. Furthermore, the cost-benefit ratio analysis showed that in Kenya, for every US$1 invested, the return benefit was US$33.92. In addition in Kenya, the investment yielded a significant net present value of US$13.7 million over a 16-year period and an attractive internal rate of return of 73% compared to the reference discount rate of 12%. The study suggests the need to facilitate further release of the parasitoid (F. arisanus) across major fruit production regions of countries affected by the invasive fruit fly (B. dorsalis). Highlights: This study presents a spatially explicit non-linear function for estimating the economic benefits at scale following parasitoid release and establishment to control an invasive fruit fly. Costs incurred in the exploration, importation, lab research, and field release were employed to estimate the return on investment in the bio-control of fruit flies using F. arisanus as an agent in Kenya. The findings will stimulate government investment in mass rearing of the parasitoid for up-scaling sustainable biological control techniques of invasive agricultural pests. [ABSTRACT FROM AUTHOR]

Riparian buffer zones (RBZs) are an important instrument for environmental policies for water and biodiversity protection in managed forests. We investigate the variation of the cost of implementing RBZs within different property size classes across the size range of non-industrial forest owner properties in Southern Sweden. Using the Heureka PlanWise decision support system, we quantified the cost of setting aside RBZs or applying alternative management in them, as the relative loss of harvest volume and of net present value per property. We did this for multiple simulated as well as real-world property distributions. The variation of cost distribution among small properties was 4.2–6.9 times higher than among large properties. The interproperty cost inequality decreased non-linearly with increasing property size and levelled off from around 200 ha. We conclude that RBZs, due to the irregular distribution of streams, cause highly unequal financial consequences for owners, with some small property owners bearing a disproportionally high cost. This adds to previous studies showing how environmental considerations differentially affect property owners. We recommend decision makers to stimulate the uptake of RBZs by alleviating these inequalities between forest owners by including appropriate cost sharing or compensation mechanisms in their design. [ABSTRACT FROM AUTHOR]

In terms of the collaborative optimization of CO2 flooding for Enhanced Oil Recovery (EOR) and CO2 sequestration, previous studies have co-optimized both cumulative oil production and CO2 sequestration by various algorithms. However, these solutions fail to optimize the CO2 injection schemes for high-water cut oil reservoirs. This paper presents an optimization methodology for CO2 flooding and sequestration in high-water cut oil reservoirs. The production optimization was carried out by adjusting the injection and production rate. To solve the proposed objective functions, the simultaneous perturbation stochastic approximation (SPSA) algorithm is applied in this paper, and the CMG-GEM module is utilized to simulate the reservoir production performance. A typical high-water cut reservoir in the Shengli oilfield was used to verify the feasibility of the presented methodology. In this paper, the production performance and net present value (NPV) for continuous gas injection under different water cuts were analyzed. The optimal timing of transforming from water flooding to gas displacement for the high-water cut reservoir was optimized. In addition, the optimal water–gas ratios for Water-Alternating-Gas (WAG) flooding were determined. The sensitivity of NPV to gas injection price and carbon subsidy was analyzed. The results show that when the gas price is 0.178 $/m3 and the carbon subsidy is 0.0169 $/m3, the optimal timing of transforming from water flooding to gas injection should be earlier than the time when the water cut is 0.82. Through the combination of NPV, cumulative oil production rate, and CO2 sequestration volume for WAG flooding, the optimal WAG ratio should be 1:2. The presented method in this paper considers various economic indicators and can optimize CO2 flooding and sequestration in high-water cut oil reservoirs efficiently, which can provide some guidance for the design of CO2 flooding schemes in high-water cut oil reservoirs. [ABSTRACT FROM AUTHOR]

Accurate travel demand forecasting is crucial before finalizing the decision to implement a public–private partnership (PPP). While government needs to determine the government payments (GPs) and level of user fee, private investors need to evaluate financial feasibility. However, travel demand forecasting involves a deep uncertain future, which relies on other exogenous forecasts. Plain reliance on the best available estimates often causes negative consequences. This study implements a many-objective robust decision-making (MORDM) framework to minimize the vulnerabilities and negative effects that deep uncertainty in travel demand forecasts might have on the PPP project. The MORDM framework is established to allow the government and private partner to pursue their objectives and identify the plausible minimum revenue guarantee and level of user fee conditions in the presence of deep uncertainties in travel demand forecasts. Results from a case study on a Korean railway PPP project illustrate that there exists a significant risk of GPs to private partners under the contracted demand incorporated within the current contract conditions. The GPs have been estimated under the current contract conditions, considerably higher than under robust contract conditions. Similarly, the net present value (NPV) under the robust contract conditions is lower than the NPV under the current contract conditions. Unlike previous approaches, the study provides an alternative to prediction-based analysis that could determine contract conditions by minimizing any negative effects caused by deep uncertainty in future outturn travel demand. [ABSTRACT FROM AUTHOR]

Purpose of the article: Olive mill wastewater raises environmental concerns due to the presence of pollutants and phytotoxic compounds. This study aims to evaluate the environmental performance of an integrated process that recycles olive mill wastewater while concurrently producing Arthrospira platensis for food applications. Methods: The quantification of the environmental impact is conducted using the life cycle assessment methodology. The environmental burden of the proposed integrated system is also compared with that of alternative wastewater treatment solutions and growing medium for microalgae cultivation considering different functional units. Eventually, a simplified economic analysis of the proposed integrated system is carried out, as a complement of the environmental assessment, to evaluate its economic competitiveness considering different market scenarios. Results and discussion: LCA characterisation results have been obtained for a set of reference scenarios using EF 3.0. The set of normalisation and weighting factors of the EF 3.0 impact assessment method is used for comparing various scenarios. In terms of aggregated score, the integrated system can reduce the environmental impact by 75.95% compared to the conventional treatment of olive mill wastewater. The use of nutrients from olive mill wastewater for the cultivation of A. platensis can potentially provide a 10.10% impact reduction compared to MF, while it is slightly higher (+ 7.5%) compared to the use of the standard Zarrouk growing medium due to the residual retentate generated in the system. An optimal retentate-free operating scenario showed a 47.38% impact decrease compared to the standard Zarrouk cultivation. The sensitivity analysis shows that transport and energy consumption have an important influence on the performance of the integrated system. The cultivation of A. platensis can be more impacting than wastewater treatment with membrane filtration if the increase of transportation distances exceeds 30 km. The economic analysis reports that the investment can be recovered in about 10 years, with a net present value of 127,000 € at 20 years, and that the cost of wastewater treatment is more influencing than the cost of electricity and the microalgae selling price. Conclusions: Based on the conducted analyses, the valorisation of nutrients from olive mill wastewater to produce A. platensis biomass can be a viable option for olive mill owners. Even though there are margins for process optimisation, this treatment solution can still offer environmental benefits and additional revenues due to the combination of avoided wastewater treatment costs and reduced microalgae production costs. [ABSTRACT FROM AUTHOR]

The high energy consumption of water bath heaters in city gate stations due to heating the passing gas is always a significant concern. A suggested approach is to apply a shell and tube heat exchanger to raise efficiency or utilize heat losses. This study first examined the impact of the geometrical parameters of a heat exchanger, e.g., baffle cut, baffle number, tube pitch, and tube diameter, on heat transfer, pressure drop, and exchanger price as objective functions and estimated the optimal point of the exchanger's geometry based on the TOPSIS algorithm. Then, the feasibility of replacing a shell and tube exchanger with a water bath heater in city gate stations was probed. The shell and tube exchanger was simulated and analyzed by Ansys Fluent software. The results showed that increases in the baffle cut from 20 to 50%, tube pitch from 1.3 to 1.9, and tube diameter from 21.3 mm to 42.2 mm reduced heat transfer by 10, 3, and 7% and pressure drop by 9, 10 and 11%, respectively, while a surge in the number of baffles from 2 to 5 raised pressure drop and heat transfer by 14 and 12%, respectively. The outcomes associated with the economic analysis of replacing an exchanger revealed that this replacement decreased fuel consumption and led to reduced contamination, on the one hand, and cost conservation, on the other hand, such that the net present value index zeroed in less than 5 years. [ABSTRACT FROM AUTHOR]

The study presents the economic feasibility assessment of converting the produced biogas from water hyacinth biomass into electricity. Approximately, 0.3793 m3CH4/kgVS was generated from the water hyacinth biomass. The research indicated that the available water hyacinth population on the Lower Volta River in the year 2020 could potentially generate a methane yield of 53.676 × 106m3. The volume of methane gas generated had the potential to produce an annual electricity output of 110.792 × 106 kWh, which could be integrated into the national grid. The economic analysis indicated positive results with an initial total investment cost of $67,273,700. The project showed a positive net present value (NPV) of $8,923,769 and a levelized cost of 0.172 $/kWh. The simple payback and equity payback periods were determined to be 5.5 and 11.3 years, respectively. Furthermore, a sensitivity analysis conducted showed that the project's NPV remained positive when variations in input parameters such as initial cost, operations, and maintenance cost were less than 15% sensitive range. However, a 30% reduction in the feed-in tariff cost resulted in a negative NPV. In conclusion, biogas production from water hyacinth biomass in Ghana can make a significant contribution to the country's energy mix and help alleviate the energy shortfall in rural areas. [ABSTRACT FROM AUTHOR]

Tiger puffer (Takifugu rubripes) is one of the most expensive farmed marine fish species in China. The high profitability of farmed tiger puffer is used to attract many new investors. However, some investments failed due to a lack of information about the tiger puffer fish farm business, poor farm and facility design, and flawed investment plans. To improve the investment efficiency and profitability of this industry, this analysis evaluated the economic performance of tiger puffer from eggs to harvest size using two different open-indoor combination aquaculture systems: a combination of recirculating aquaculture system and open net pen (RAS+ONP) and a combination of flow-through system and earth pond (FTS + EP). This analysis evaluated the financial performance of both systems using profit margin, net present value (NPV), internal rate of return (IRR), and payback period. At the same time, a sensitivity analysis was employed to measure economic risk. The results revealed that despite the RAS+ONP system being more economically profitable than the FTS + EP system, the financial indicators of the FTS + EP system granted a better economic performance in terms of NPV and IRR due to lower initial investment and operating costs. Meanwhile, the sensitivity analysis revealed that the economic performance of both systems was vulnerable to the fluctuations in fish prices and feed prices. The potential risk of earning profit was higher for the RAS+ONP if the feed price fluctuated compared to the FTS + EP system, while the risk was higher for the FTS + EP if the fish price fluctuated. Hence, the FTS + EP system could represent an opportunity for new entrants to obtain a more profitable production. [ABSTRACT FROM AUTHOR]

In this study, the optimization of the location of oil production and injection wells, the number of production and injection wells, and the economic evaluation in the water injection process has been carried out using three algorithms: PSO, GA, and HGAPSO. Optimizing the oil extraction process by optimizing well locations, the optimal number of production and injection wells, and economic evaluation can improve the performance and efficiency of the process. In this study, the optimization of the water injection process into oil reservoirs using the PSO, GA, and HGAPSO algorithms has been addressed. Additionally, economic evaluation, considering costs and profits from oil production using the best-optimized parameters, has been conducted, and the best Net Present Value (NPV) has been calculated. Initially, the optimal well location problem is modeled, taking into account reservoir characteristics and geological conditions. Using the PSO and GA algorithms, the best well location and number of water injection wells have been obtained, leading to improved efficiency and cost reduction. Then, the GA algorithm is used to combine and modify viewpoints and optimize the number and location of wells. This algorithm explores optimal solutions in the well location space. Economic evaluation is performed using the best-optimized parameters by the algorithms. Costs of water injection, oil production costs, and profits from increased oil production are considered. By calculating the best Net Present Value (NPV), optimal decisions regarding the water injection process and enhancing the performance of oil reservoirs are made. Simulation results indicate that the GA algorithm outperforms other algorithms and can be used as a robust and effective method for optimizing well locations and the number of production and injection wells in the oil injection process. Ultimately, this study assists the oil industry in making better decisions about optimizing water injection and improving the efficiency and profitability of the process using the introduced optimization algorithms. [ABSTRACT FROM AUTHOR]

Organic aquaculture is a new approach in the modern farming system. As the capital investment is higher for setting up the organic aquaculture, it is essential to conduct an economic feasibility study with compare the conventional farming system. In the current study, economic feasibility of culturing Indian major carps (IMC) using conventional culture system and organic culture system (OCS) were evaluated. IMC was cultured for three consecutive years from 2017 to 2019 in experimental ponds of 0.015 hectare (ha) area each. The crude protein content of the organic and conventional feed was maintained at the same iso-nitrogenous level (32% crude protein) but the highest production to the tune of 19 tons per ha was obtained in OCS. Further, in case of OCS, apart from fish production, vermicomposting to the tune of 45,000 kg ha−1 in the first year, and 90,000 kg ha−1 from second year onward is achievable by installing a vermicomposting unit of 200 tons annual capacity. Economic analysis of the culture systems assuming a project period of 10 years showed that the highest net present value (NPV) of 1.06 million USD, a payback period of one year and nine months and an internal rate of return (IRR) of 51% are achievable per ha of fish culture pond for OCS. Sensitivity analysis of various costs performed for OCS revealed that profitability of the organic fish farming investment is most sensitive to the total fish production and sale price of the organic fishes. In terms of production of fish and economics of organic culture system is proved to be the best available technique. [ABSTRACT FROM AUTHOR]

The study aims to rapidly scale up Hybrid Renewable Energy System (HRES) specifically emphasizing bioenergy generation for isolated rural communities. It aims to identify the most profitable and efficient configuration for HRES biomass-solar in João Pinheiro, taking advantage of local eucalyptus production to reduce costs associated with the transport of biomass waste, considering energy, economic and ecological indicators. Eucalyptus waste was chosen as the source of biomass as fuel, the Downdraft gasifier with air as the gasification agent, and monocrystalline silicon technology was selected for photovoltaic modules. Two case study scenarios were proposed based on global efficiency calculations. The techno-economic analysis was applied based on the First Law of Thermodynamics and the Levelized Cost of Electricity (LCOE) method. Case 2 showed the overall energy efficiency of 17.43% and LCOE 0.034 US$/kWh more suitable for HRES solar-biomass technology. Additionally, the eco-efficiency indicator indicator based on the calculated Net Present Value and ecological efficiency indicator, allowed evaluation of the relationship between added value and the environmental impacts associated with the studied configurations, with case 2 presenting 9.28e−05 kgCO2/US$ as best result. The conclusions show that the techno-economic analysis applied to the HRES syngas-solar, along with the eco-efficiency indicator, presents the viability of decentralized bioenergy supply, particularly in isolated rural communities. This innovative approach encourages sustainable measures to meet energy needs in isolated regions with climatic, environmental and biomass supply conditions like those of João Pinheiro. Highlights: Overall efficiency of the Biomass-Solar HRES can range from 14% to 17.8%. Biomass-solar HRES makes LCOE smaller compared to isolated subsystems. The higher the pollutant indicator, the lower the environmental efficiency. Syngas has better eco-efficiency than diesel, and B20 biodiesel. Biomass-solar HRES can meet energy demands of isolated regions with local resources. [ABSTRACT FROM AUTHOR]

The article presents an economic and analytical model that evaluates various criteria for the effectiveness of investments in spent nuclear fuel reprocessing plants at given capital, operating, and decommissioning costs, as well as expected project implementation deadlines. The model also solves the inverse problem of determining the requirements for plant parameters based on the criteria of investment effectiveness. The results of the calculation of the most important of these parameters, including the internal rate of return, the discounted payback period, and the levelized cost of reprocessing spent nuclear fuel, are presented. The mathematical definition of the net present value, representing the main criterion, depends on the plant capacity, which varies from 200 to 3000 t of fuel per year. The estimated conditions under which the net present value of reprocessing spent nuclear fuel does not exceed $1000/kg are presented. [ABSTRACT FROM AUTHOR]

The growing demand for primary mineral resources and the finite nature of mineral reserves necessitate their efficient utilization while minimizing losses. To extend mine life and increase economic reserves, transitioning from open-pit to underground mining has proven to be a viable strategy. Identifying this critical transition depth is pivotal, as it significantly impacts mining profitability. Therefore, in this paper we propose a method to determine the open-pit/underground transition depth based on an economic block model, accounting for the final pit limit and considering the inherent uncertainty in mineral prices. To achieve our research aim, a hypothetical grade model was constructed initially, and we used @Risk software to perform Monte Carlo simulation of copper prices based on historical data. By generating 200 different mineral price scenarios, we created 200 economic block models. Subsequently, nine mining sequences were designed, and seven distinct scenarios were established to ascertain the final open-pit limit and the depth of the transition point between mining methods, contingent on fluctuating mineral prices. Based on the outcomes derived from the seven scenarios, the depth at which the mining method transition from open-pit to underground is recommended to be 375 m from the surface, under the aforementioned uncertainties. This recommendation is based on the cumulative net present value of open-pit/underground mining, as illustrated in scenario number 7. Our findings provide valuable insights for mining companies seeking to optimize resource utilization and maximize profitability while navigating uncertain mineral price environments. [ABSTRACT FROM AUTHOR]

The road network is a major asset for every developing nation. Data collection, analysis, and arriving at economical maintenance work plans are said to be major goals for every road agency. Successful implementation of Pavement Management Systems can result in ease of decision-making about investments incurred for the maintenance of road networks. Advanced pavement maintenance strategies ensure the rational utilisation of limited funds scientifically. Based on existing pavement conditions, a systematic procedure is required to analyse the impacts of different maintenance strategies based on the predicted future pavement conditions. The present study attempts to develop a prioritised work programme for an identified non-core road network in India using the Highway Development and Management tool. Pavement distress data for non-core roads with a total length of 1743.9 km were collected using a Network Survey Vehicle and stored in a customised central database. Six maintenance strategies were formulated and predicted the International Roughness Index values, and they were compared with those obtained from the conventional maintenance strategy adopted by the state agency. Furthermore, an economic analysis was carried out, and the best strategy was proposed based on optimised costs. The predicted International Roughness Index (IRI) from the proposed strategy was found to be 37% lower than the predicted IRI using a conventionally adopted maintenance strategy. Such road asset management studies should be popularised by the state public works department for non-core roads to optimise the resources. [ABSTRACT FROM AUTHOR]

A surge in energy demand driven by the growing number of buildings and insufficient attention to sustainable and optimised energy-saving procedures are likely to threaten the economy and the environment. The building envelope is a significant component that influences energy requirements, directly affecting the operations costs. Thus, the current study considers the envelope to optimise the building's Life Cycle Costing (LCC) and enhance energy efficiency. Therefore, to achieve the aim of the study, Building Information Modelling (BIM) with the integration of Life Cycle Cost Analysis (LCCA) is adopted to assess the building envelope and optimise energy use and relevant costs. Three alternatives of wall system: brick wall with rockwool insulation, brick wall with polystyrene insulation and curtain walls system, are considered for the building envelope to enhance energy-saving potential by analysing and comparing the energy demand. To determine LCCA, the Net Present Value (NPV) approach was adopted for the initial expenditure and the associated future costs. It was found that utilising insulation material with low thermal conductivity reduces heating and cooling energy resulting optimised LCC. Compared to curtain walls, the results show that the rockwool insulated wall reduces 17% of energy demand while the polystyrene wall reduces 12.7% of the energy. Similarly, rockwool insulated walls save 5% energy relative to the wall system with polystyrene insulation. Thus, integrating LCCA with the BIM approach at the conceptual design stages promotes energy and LCC optimisation. [ABSTRACT FROM AUTHOR]

Smallholder farmers in Tigray have been growing Rhamnus prinoides trees/shrubs with annual crops in rain-fed farmlands. Although this agroforestry system is widely practiced, there are no sufficient scientific reports on its profitability and financial returns. The objective of this research was to analyze the financial profitability and relative financial advantages of R. prinoid-based agroforestry compared to monocropping practices, in eastern Tigray. Data were collected using a structured questionnaire from 123 randomly selected households who practiced R. prinoides-based agroforestry. To address the objective, we estimated the net present values (NPV), Annuity values, and benefit to cost ratio (BCR) on per hectare basis. The annuity and BCR of agroforestry were compared with those of adjacent monoculture farms of the associated crop components in agroforestry. The land equivalent ratios (LER) of the agroforestry were calculated and compared with sole crops. The NPV and BCR of the agroforestry were 5.6 and nearly fourfold higher than that of the monocropping, respectively. Similarly, the R. prinoides-based agroforestry LER was 0.33–1.36% higher as compared to monocultures. Stocking density and age of agroforestry affected the financial return from R. prinoides-based agroforestry. We concluded that R. prinoides-based agroforestry has superior financial performance over monocrops and is financially less risky. Therefore, the adoption of R. prinoides-based agroforestry practices is a viable option for smallholder farmers to maximize net returns from their rain-fed farmlands and resource inputs. [ABSTRACT FROM AUTHOR]

We develop a method for extracting "other information" from the articulation between bottom-line accounting numbers and stock prices. We posit that "other information" captures future earnings growth originating from conservative accounting recognition principles as demonstrated by Penman and Zhang (2020) and Penman and Zhu (2022), as well as nonzero net present value investment opportunities. Our findings confirm that "other information" is strongly associated with various proxies for expected future earnings growth and firm risk attributes. Furthermore, we show how a structural expected return model incorporating our "other information" estimate can predict out-of-sample future stock returns and generate sizeable long-short return spreads. [ABSTRACT FROM AUTHOR]

Petroleum spent hydroprocessing catalysts are hazardous solid waste, the efficient recycling of which is a serious challenge to refineries. However, information on the economic feasibility of spent catalysts recycling plants is scarce, which is critical for environmental authorities and decision-makers. In this work, an innovative recycling scheme targeting hydrometallurgical recovery of base metals (Ni, Mo, and V) and transforming low-value Al residue into a high-value boehmite (γ-AlOOH) as the key product was considered an efficient way to beneficiate the hazardous spent hydroprocessing catalysts. A preliminary techno-economic evaluation of such a recycling scheme was performed to assess the feasibility of the proposed recycling scheme. The recovery cost (valuable metals and boehmite) and potential revenue were estimated to study the economics of the process. The preliminary results have suggested that the recycling scheme is economically feasible with a high internal rate of return (IRR) of 12.3%, a net present value of 38.6 million USD, and a short payback period of 8.7 years. Furthermore, a sensitivity analysis (± 10%) conducted on key parameters showed that the selling prices of the finished products and the cost of chemicals were the most important factors affecting plant economics. Overall, the recycling scheme was sustainable and avoided landfilling of spent catalysts as the residue can be beneficiated into a high-value product. The results from the economic feasibility study are likely to assist the stakeholders and decision-makers in making investment and policy decisions for the valorization of spent hydroprocessing catalysts. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The building consumes almost 40% of the energy generated in the building. Investigating the photovoltaic system, wind, battery, and diesel generators for residential buildings can reduce energy utilization. In this work, various energy sources are combined to form hybrid energy sources, which are designed based on the load of the residential building. The Hybrid Optimization of Multiple Energy Resources tool optimizes various energy sources such as photovoltaic (PV), wind, diesel generator (DG), and battery. An investigation on the residential load in the smart city of Coimbatore, Tamil Nadu, India, is being carried out. This article examined the technological and economic feasibility of solar photovoltaic, wind, diesel generators, and batteries combined to form a hybrid energy source (HES). With 2 kW of photovoltaic, 1 kW wind, 1 kW of DG, 1 kW of the power converter, and five batteries, system case 1 (photovoltaic/wind/diesel generator/battery model) had the best results in the simulation and was recommended for use in the proposed residential building. As a result, it has a minimum net present value of $14,568 and an energy cost of $0.312/kWh, which is about 39% cheaper than system base cases. The sensitivity and environmental analysis are carried out to analyze the system's feasibility. [ABSTRACT FROM AUTHOR]

Due to a wide variety of real-world constraints, proper project portfolio selection is a critical issue for project-oriented organizations. In this paper, a bi-objective stochastic mixed-integer linear programming model is developed to cope with the project selection and scheduling problem in the presence of greenhouse gas emissions, and non-hazardous/hazardous wastes regulatory restrictions. Moreover, reinvesting proceeds of projects as well as loans are allowed to finance projects over the planning horizon. The proposed model maximizes the net present value of the expected project portfolio's terminal wealth under uncertain conditions, as well as the sustainability score of the project portfolio, simultaneously. The sustainability score is calculated by one of the recent multi-criteria decision-making methods, SECA, based on seven qualitative sustainability indicators and by solving a non-linear optimization model. To assess the performance of the proposed model, a case study of eighteen industrial projects is applied. Since the duration of industrial projects is usually uncertain, the proposed model is reformulated as a scenario-based stochastic programming model. Furthermore, the CPLEX solver and Branch and Benders algorithm are used to solve the problem. Results show that the Branch and Benders algorithm is much more efficient than the CPLEX solver. Results show that increasing the carbon and landfill tax rates is not always an appropriate decision made by policymakers to control various types of emissions. Such decisions may not only make the projects less attractive for investment but also, do not significantly reduce the negative environmental effects, which decreases sustainability in both economic and environmental dimensions. This highlights the importance of considering each problem's attitudes for setting regulations where copying does not always create the same solutions for sustainability issues. [ABSTRACT FROM AUTHOR]

Air conditioning consumes over 55% of electricity in countries like Saudi Arabia. A solar-assisted absorption chiller can significantly reduce energy consumption. The aim of this study is to introduce and evaluate the performance of solar-assisted absorption chiller under different weather conditions in different cities by developing a mathematical model and solving it using the Engineering Equation Solver code. The insights derived from this research hold significant relevance for countries with similar climatic conditions. Weather conditions and collector type have a direct impact on a chiller's Coefficient of Performance (COP). In Najran (South of Saudi Arabia), the use of a Flat Plate Collector yields a COP of approximately 0.6853, while an Evacuated Tube Collector (ETC) achieves a higher COP of 0.7412. Conversely, in Al-Khafji (Northeast of Saudi Arabia), the COP drops, with a FPC to 0.574 and to 0.7108 with an ETC. Economically, the study confirms that the system in Najran, equipped with ETC, outperforms that at any other city studied. With a 50-kW cooling capacity using yearly average Global Tilt (GT) radiation, the system at $984.32/kW boasts a 9.91-year payback period and a $52,742 net present value, 21.7%, 19.6%, and 18.2% lower than relying on minimum monthly average GT radiation, respectively. Despite higher costs, prioritizing monthly average GT radiation proves more effective for cooling demand. Finally, The Najran system, with a net present value (NPV) of $62,641 based on minimum monthly average GT radiation, is economically superior to the vapor compression chiller with NPV of $85,264. [ABSTRACT FROM AUTHOR]

Charcoal production stemming from small-scale Eucalyptus camaldulensis plantations has brought about significant socio-economic benefits and improved livelihoods in Ethiopia. Nevertheless, the current practice involves the use of traditional earth mound kilns, leading to inefficiencies, reduced charcoal income, and environmental pollution. This research aims to assess charcoal conversion efficiency, perform a cost–benefit analysis, and measure gas emissions from improved charcoal-making kilns sourced from Eucalyptus camaldulensis small-scale plantations in comparison to traditional earth mound kilns in northwestern Ethiopia. A one-way analysis of variance (ANOVA) was executed, with a significance level set at 0.05. The study results indicate a significant (P < 0.001) disparity in charcoal conversion efficiency across the various tested kilns, with the ranking as follows: Green mad retort kiln (33.7%) > Casamance kiln (32.09%) > MRV steel kiln (28.25%) > traditional earth mound kilns (23.55%). The improved charcoal-making kilns enhanced wood-to-charcoal conversion efficiency by 20–43% compared to traditional earth mound kilns. In terms of financial viability, Casamance improved kilns generated the highest equivalent annual charcoal income (117,126.9 ETB/year), followed by Green Mad Retort (82,893.8 ETB/year) and MRV steel kilns (58,495.9 ETB/year). As anticipated, traditional earth mound kilns yielded the lowest net present value (47,304.3 ETB/year). Traditional earth mound kilns also exhibited significantly longer carbonization times (P < 0.001), taking 3.6 times longer than the Mark V kiln and 2 times longer than the Casamance kiln. Furthermore, the statistical analysis demonstrated that improved charcoal-making technology reduced carbon dioxide (CO2) emissions by 36.1–50.7%, carbon monoxide (CO) emissions by 39.2–54.3%, and methane (CH4) emissions by 29.6–47%. In conclusion, the use of improved charcoal-making kilns has demonstrated significant enhancements in charcoal conversion efficiency, charcoal income, and environmental sustainability. Given these positive outcomes, we strongly recommend a decisive transition from traditional to cleaner, sustainable, and less emissions-intensive charcoal making kilns. [ABSTRACT FROM AUTHOR]

The parabolic trough collector (PTC) is one of the most well-established concentrating technologies, and it has been used as a heat source in a wide range of thermal applications which demand relatively higher operating temperatures (about 400 ºC). In the present research, a two-dimensional numerical methodology implemented on EES software (Engineering Equation Solver) is proposed to predict energetic and exergetic performances of commercial PTC modules of EuroTrough ET-150 by considering the discretization of the receiver along with the main flow direction. Different mass flow rates of Therminol VP-1 and Molten Salt (NaNO3 (60%)–KNO3 (40%)) heat transfer fluids, receiver diameters and solar beam radiation levels are considered. According to the sensitivity analyses, for turbulent and laminar/transition flow conditions the number of divisions/segments of the PTC module to stabilize the values of useful gain, heat loss and irreversibility of the PTC receiver is 20 and 100 divisions, respectively. The validated model is used to perform detailed energetic and exergetic analyses of a PTC array with eight modules in series, in which the PTC modules are firstly analysed individually and after at an overall thermal performance way. In the second part of this research is presented a case study for the application of ET-150 modules using Therminol VP-1 as heat source for a 3.9 MW Organic Rankine Cycle (ORC) operating under environmental conditions of the Northeast region of Brazil, taking into account its thermo-economic viability. According to thermo-economic assessment, the highest values of Net Present Value (NPV) and Internal Rate of Return (IRR) are achieved for Gb = 700 W m−2 and mass flow rate of 1 kg s−1. Moreover, for the ORC coupled with fifty rows of PTC and eight modules in a row, the NPV could reach 40 million dollars with about 25% of IRR if exemption from taxes is applied. [ABSTRACT FROM AUTHOR]

The energy transition to a low-carbon economy involves adoption of cleaner production and energy technologies while the global energy demand continues to rise. Low-emission gas-to-wire firing low-quality natural gas from deep-water offshore fields emerges as a solution that can accelerate the energy transition without compromising energy and environment securities. The present work considers an innovative design of low-emission floating gas-to-wire co-firing CO2-rich natural gas and blue-H2 (NG-H2-GTW-CCS) and evaluates it against a conventional low-emission gas-to-wire (NG-GTW-CCS) firing only CO2-rich natural gas. Both alternatives implement capture and geological storage of CO2 in the oil reservoir for enhanced oil recovery. The NG-H2-GTW-CCS sends part of the CO2-rich natural gas feed to dry autothermal reforming coupled to pre-combustion carbon capture, producing blue-H2 and co-firing it with CO2-rich natural gas. The sustainability assessment follows TOPSIS method (technique for order of preference by similarity to ideal solution) through process simulation. Results show that NG-GTW-CCS achieves a net power of 525.58 MW, while NG-H2-GTW-CCS achieves 524.67, 541.77, and 591.24 MW with blue-H2 at, respectively, 10%mol, 30%mol, and 50%mol in the fuel-blend. The net present value of NG-GTW-CCS is 2666.3 MMUSD while NG-H2-GTW-CCS reaches 2000.2, 2253.3, and 2412.0 MMUSD (at 10%mol, 30%mol, and 50%mol blue-H2). It is shown that the sustainability degree of process alternatives co-firing blue-H2 outperform the conventional NG-GTW-CCS counterpart. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this research is to carry out a literature review on the use of life-cycle cost (LCC) approaches for hydrogen technologies, by analysing its evolution over a decade (2012–2021). Methods: The SCOPUS database has been used to select relevant literature on the subject. After adoption of inclusion/exclusion criteria, a total of 67 papers were selected for our review. Then, we analysed these studies in terms of hydrogen technologies (fuel cells, electrolysers, hydrogen storage approach, etc.) covered by the LCC approaches. In addition, we also performed an analysis of the LCC features — type of LCC (conventional, environmental, social), integration with LCA/S-LCA, guidelines followed, system boundaries (cradle-to-farm gate, cradle-to-consumer, cradle-to-grave, cradle-to-cradle), functional units, financial tools (NPV, BEP, etc.), type of costs included, and life span — to provide a comprehensive view of LCC studies applied to hydrogen technologies. We also discussed and interpreted the most significant findings. Results and discussion: Our main results can be summarised as follows: (i) the number of LCC studies for application to hydrogen technologies has increased in the decade 2012–2021; (ii) China is the leading country for number of publications on the subject (15 papers), even if the most prolific author and institution are Iranians; (iii) a large number of studies performed LCC analysis including fuel cells and/or electrolysers based on proton exchange membranes; (iv) the most widely used LCC approach is a cradle-to-consumer (37 papers); (vi) almost all the studies on LCC of hydrogen technologies included initial, operation and maintenance costs; while other costs — replacement, external, end-of-life — are included in a limited number of papers; (vii) the net present value (NPV) is the most used financial tool. Conclusions: LCC analysis for application to hydrogen technologies has gained interest in recent years. However, the number of studies that explicitly follow LCC or LCA guidelines is very limited (only 7). The life-cycle cost analyses performed are quite incomplete in terms of costs included in the life-cycle stages. Besides, there is a lack of information and uniformity in the use of functional units and financial tools. [ABSTRACT FROM AUTHOR]

The economic feasibility for captive breeding of marine ornamental fish in small spaces is poorly known, especially when considering threatened species. The present study analyzed the economic feasibility for producing Yellow Neon Goby (Elacatinus figaro) (vulnerable) in urban aquaculture systems through different production scenarios: pessimistic, normal, and optimistic, at sales prices of US$ 5.71, US$ 7.62, and US$ 9.52/unit. The financial analysis pointed the total cost of production per animal available to marine ornamental fish trade was between US$ 3.99 and R$ 8.03, with labor and rent as the main expenses. Six of the nine observed schemes showed profitability, including under loss conditions of an entire cycle. The net present value (NPV 8%) reached US$ 83,256 (negative value, unfeasible) until US$ 230,122 (positive value, viable), with profitable conditions presenting an internal rate of return (IRR) ranging from 10.87 to 97.84% and return on capital observed from the first to the sixth year of activity. In addition to the sustainable potential for biodiversity conservation, these results expressed reinforce urban ornamental aquaculture as a profitable instrument for public policy in socioeconomic development at large urban centers and their peripheral regions. [ABSTRACT FROM AUTHOR]

The dynamic model of the biogas project was created with changing parameter values over time and compared to the static model of the same project based on constant values of the same parameters. For the dynamic model, the same methods were used to evaluate the biogas project as for the static model to calculate substrate mix volumes, costs, farm production volumes, number of biogas plant equipment, driers, and other numerical characteristics of the farm. Project risks were evaluated by the sensitivity analysis and Monte Carlo simulation. The study was conducted for four scenarios regarding the substrate mix structure and the possibility of selling electricity on the market. In the scenarios, the scale of the project was determined by the size and structure of agricultural and biogas production. The results have shown that when only wastes are used as substrates, net present values (NPVs) of the project are equal to 29.45 and 56.50 M RUB in dependence on the possibility to sell electricity on the market. At the same time, when the substrate mix is diversified, the project NPVs are equal to 89.17 and 186.68 M RUB depending on the ability to sell all the produced electricity to the common power grid. The results of the sensitivity analysis defined that the values of elasticity coefficients are less than 3.14%. Results of the Monte Carlo simulation have shown a probability distribution of positive NPVs for each scenario. This study was conducted to make recommendations for business and municipalities. [ABSTRACT FROM AUTHOR]