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After the expiration of each lease, lessees may return leased equipment on schedule, renew the lease or purchase it according to the equipment status and their demands. By considering lessees' uncertain options and equipment status difference, the pricing and inventory decision-makings of leased equipment are explored. A mixed-integer nonlinear programming model by maximising the net present value of lessor's profit is presented with respect to constraints like rental revenue, manufacturing, lessees' credit check, transportation, maintenance, upgrade and inventory costs. The rental price and inventory decisions are obtained by solving the problem with a particle swarm optimisation algorithm. We also analyse the impacts of purchasing cost of old equipment from a third-party supplier on lessor's inventory, renewal price or purchasing price of leased equipment on lessees' options and lessor's profit. The results show: (1) with the extension of lease period, the rental price increases while the growth rate decreases; (2) the maintenance cost accounts for about 20% of total cost, and the preventive maintenance strategy can reduce excess maintenance cost as lease period increases; (3) the lessor shall set moderate renewal price discount coefficient and purchasing price coefficient, and analyse purchasing cost of old equipment to manage inventory timely. [ABSTRACT FROM AUTHOR]

The extensive use of external thermal insulation composite systems (ETICS) using expanded polystyrene (EPS) for building insulation in Germany has resulted in accumulating end-of-life EPS-ETICS. To address limited waste management options and enhance EPS circularity, alternative recycling options like pyrolysis or solvent-based recycling need to be implemented. However, efficient recycling requires ex-ante analyses of the corresponding reverse logistics networks, including all necessary pre-treatment and transport processes. This study aims to develop a decision support system to determine optimal EPS-ETICS waste management by minimising the net present value of the corresponding network design. Our mixed-integer linear optimisation model considers decisions on technology, capacity, and location for pre-processing and recycling facilities as well as on material flow allocation. Applied to a German case study, our model finds pyrolysis and solvent-based recycling economically superior to current waste treatment in waste incineration plants. We present an optimal network design combining central pyrolysis with decentral pre-processing. A scenario analysis shows fluctuating styrene and polystyrene prices might favour solvent-based recycling over the optimal choice in pyrolysis, with minor overall cost differences. Further, legal recycling quotas of at least 40% would be necessary to promote solvent-based recycling and enhance EPS circularity beyond what is achievable through pyrolysis. [ABSTRACT FROM AUTHOR]

This paper investigates the association between life insurers' voluntary disclosure of embedded value (EV), an unregulated market-driven fair value measure, and analyst forecast accuracy and dispersion. EV is an estimate of the present value of future net cash flows from in-force life insurance business. Advocates of this disclosure believe that EV is a better measure of economic performance than traditional GAAP measures. Others argue that corporate management has discretion in estimating and reporting EV. Further, analysts may have access to information that allows the development of possibly more accurate estimation metrics in the absence of EV disclosure. It is then an empirical issue to determine whether EV disclosure has any incremental effect on analysts' forecast properties. Using a multi-country setting, we find that EV disclosure is positively associated with analysts' earnings forecast accuracy and negatively related to forecast dispersion. This result is consistent with the alternative hypothesis that disclosure of EV provides a richer information set that enriches analysts' forecasts beyond their own in-house developed surrogates. As guidance for insurance accounting and disclosure evolves, our findings support the value of continuing to provide EV information to the public. [ABSTRACT FROM AUTHOR]

We develop a double-sided moral hazard model of social entrepreneurship and derive the optimal state subsidy. Then, we analyze the data of an EU-funded training and mentoring program aiming at preparing social entrepreneurs for private financing. Using content analysis techniques, we investigate the 203 applications for the program, the reviewers' evaluation, and the selection decision. Social enterprises produce private and public benefits, use market and non-market resources, and involve a wide range of stakeholders with different incentives. We examine why different projects can get active financing (financing plus advisory), or only passive financing (financing without advisory), or no financing at all. We identify five relevant selection criteria such as entrepreneurial net present value, entrepreneurial agency cost, advisory net present value, advisory agency cost, and the external effects of the project. Empirical findings are consistent with the theoretical model. Applicants with higher scores in business plan, social impact, and geographical scope were significantly more likely to be selected, especially if their activities required no domain-specific knowledge from the advisors. However, higher agency costs, reflected in too many business lines and early-stage operations, seem to reduce the chances significantly. We formulate a moral hazard model for social entrepreneurship with four simultaneously optimizing players: an entrepreneur, an investor, an advisor, and the state. With the help of our unique database, we get valuable insights into the financing decisions of a profit-seeking investor. Our findings can contribute to the improvement of the design of state-subsidized social entrepreneurship programs. [ABSTRACT FROM AUTHOR]

Optimizing well placement is one of the primary challenges in oil field development. The number and positions of wells must be carefully considered, as it is directly related to the infrastructure cost and the profits over the field's life cycle. In this paper, we propose three estimation of distribution algorithms to optimize well placement with the objective of maximizing the net present value. The methods are guided by an elite set of solutions and are able to obtain multiple local optima in a single run. We also present an auxiliary regression model to preemptively discard candidate solutions with poor performance prediction, thus avoiding running computationally expensive simulations for unpromising candidates. The model is trained with the data obtained during the search process and does not require previous training. Our algorithms yielded a significant improvement compared to a state-of-the-art reference method from the literature, as evidenced by computational experiments with two benchmarks. [ABSTRACT FROM AUTHOR]

This article addresses the financial viability of agents in the robusta coffee sector. The objective is to calculate and analyze the profitability performance of the coffee sector in Tshopo in order to inform the subsequent development of business projects in the robusta coffee sector. Moreover, the analysis will assist decision-makers and investors in determining the optimal allocation of funds to the most profitable links in the robusta coffee sector in Tshopo. A cost-benefit analysis was conducted, employing a discounting methodology to evaluate the cash flows of agents engaged in the robusta coffee sector. This entailed the calculation of the net present value, internal rate of return, and payback period. The results demonstrate that the coffee sector is performing well, with agents' cash flow sufficient to repay the initial investment. It can thus be concluded that, in consideration of the favorable profitability criteria, there is minimal risk in investing in the robusta coffee sector in Tshopo. [ABSTRACT FROM AUTHOR]

In response to declining electricity production in Zimbabwe, the energy regulator engaged various stakeholders to work together to solve the energy shortage problem. Biomass waste, abundant in the country, can contribute to electricity generation for consumption and export to the grid. Compared to other renewable energy resources such as wind and solar, biomass has lower investment and per unit operational costs, making it more affordable. Although farmers in the remote off-grid areas produce large amounts of waste, which can be used for biogas production via anaerobic digestion (AD), the farmers are still 'energy-poor'. There is insufficient information to enable farmers to make informed decisions on AD technology uptake. This study conducted a techno-economic assessment for a mini biogas electric plant (MBEP) for a typical farm in Zimbabwe's off-grid areas. The sustainably available biomass for biogas production was determined, followed by quantifying the biogas produced, sizing and selecting the digester type, and sizing the generator. The MBEP produces 435,350.7 kWh of heat and electrical energy from 452 t of biowaste. The first biodigester-type option, the garage-shaped, has a negative net present value ( NPV ) of − US$416.4. The Carmatec biodigester, the most popular AD technology in the country, has a positive NPV (US$216,447.7), but its economics needs improvement. Adopting AD technology allows farmers to mitigate environmental pollution and improve soil fertility by converting organic waste into biogas and biofertilisers and promoting sustainable agricultural practices. Research was recommended to investigate supportive policies, incentives, and regulatory frameworks to promote the widespread adoption of AD technology in agricultural settings. [ABSTRACT FROM AUTHOR]

This research investigates the design and optimization of a photovoltaic (PV) water pumping system to address seasonal water demands across five locations with varying elevation heads. The system draws water from a deep well with a static water level of 30 m and a dynamic level of 50 m, serving agricultural and livestock needs. The objective of this study is to accurately size a PV system that balances energy generation and demand while minimizing grid dependency. Meanwhile, the study presents a comprehensive methodology to calculate flow rates, pumping power, daily energy consumption, and system capacity. Therefore, the PV system rating, energy output, and economic performance were evaluated using metrics such as discounted payback period (DPP), net present value (NPV), and sensitivity analysis. The results show that a 2.74 kWp PV system is optimal, producing 4767 kWh/year to meet the system's annual energy demand of 4686 kWh. In summer, energy demand peaks at 1532.7 kWh, while in winter, it drops to 692.1 kWh. Meanwhile, flow rates range from 11.71 m3/h at 57 m head to 10.49 m3/h at 70 m head, demonstrating the system's adaptability to diverse hydraulic conditions. Economic analysis reveals that at a 5% interest rate and an electricity price of $0.15/kWh, the NPV is $6981.82 with a DPP of 3.76 years. However, a 30% increase in electricity prices improves the NPV to $10,005.18 and shortens the DPP to 2.76 years, whereas a 20% interest rate reduces the NPV to $1038.79 and extends the DPP to 6.08 years. Nevertheless, the annual PV energy generation exceeds total energy demand by 81 kWh, reducing grid dependency and lowering electricity costs. Additionally, the PV system avoids approximately 3956.6 kg of CO2 emissions annually, underscoring its environmental benefits over traditional pumping systems. As a result, this study highlights the economic and environmental viability of PV-powered water pumping systems, offering actionable insights for sustainable energy solutions in agriculture. [ABSTRACT FROM AUTHOR]

This study explores the performance of an innovative, techno-efficient multigeneration plant incorporating a three-stage reverse osmosis (RO) unit, focusing on the exergy-cost-environment nexus. The plant's performance is validated through comparisons with existing literature, and parametric analyses are conducted to assess the impact of critical parameters. The system demonstrates the capability to produce 720.1 kW of net electricity and sustain a hydrogen production rate of 0.05083 kg/s, achieving energetic and exergetic efficiencies of 17.82% and 23.88%, respectively. Economically, the system offers a sum unit cost of products (SUCP) of 33.33 $/GJ, showcasing its financial viability. Environmental and sustainability metrics, including an emission rate of 0.000267 kg CO₂/kWh, an exergy stability factor of 0.9341, and an exergo-environment index of 17.21, underscore the plant's eco-efficiency. A sensitivity analysis of the RO membrane recovery rate reveals an optimal balance between improved performance and economic feasibility. Excessive recovery rates adversely impact costs. The economic evaluation, using the Net Present Value (NPV) method, indicates a payback period of 9 years with significant profitability projected by the 20th year. This comprehensive analysis confirms the plant's potential for efficient and sustainable multigeneration. • Proposing a cutting-edge multi-generation plant with environmental viability. • The economic analysis forecasts a return on investment within 9 years. • The minimization of reactor temperatures has positive effect on the performance. [ABSTRACT FROM AUTHOR]

This study examines the integration of multi-real-option valuation and security token offering (STO) as an innovative approach to real estate project financing. The case study of Aspen Resort Development serves to illustrate this methodology. The traditional discounted cash flow (DCF) method is frequently ill-suited to the dynamic and uncertain nature of long-term real estate projects, particularly in regard to the ability to adapt to market fluctuations. In order to address these limitations, this study employs a multi-real-option model with a binomial lattice framework, thereby facilitating flexible decision-making in various investment stages. The analysis demonstrates that the STO-based project financing (STO-PF) model offers enhanced financial performance and strategic advantages in comparison to the conventional DCF approach. Furthermore, the STO-PF model has the effect of increasing liquidity, expanding investment accessibility, and improving risk management through the utilization of digital platforms. By quantifying the project's extended net present value (ENPV), the integration of STOs with real-options models can facilitate optimal investment decisions in the context of a high level of market volatility. Consequently, the STO-PF model is determined to yield a project value (E) of USD 7.34 million and a real-options value (ROV) of USD 3.69 million. This is markedly higher than the net present value (NPV) of USD 3.65 million derived from the traditional project finance (PF) model. Furthermore, the put option for the second investment stage contributes USD 16.45 million to the overall value of the project, thereby demonstrating the flexibility and strategic advantages of the STO framework in comparison to static NPV analysis. The Aspen project serves as a case study, demonstrating the financial viability of phased investments in dynamic market conditions. It contributes to the theoretical understanding of STO-based financing and provides practical insights for developers seeking flexible and innovative financing solutions in the real estate sector. Further research is required to confirm the applicability of STOs in diverse market environments and regulatory contexts. Additionally, in-depth research is necessary to integrate emerging technologies, such as artificial intelligence and machine learning, into multi-real-option-based financial platforms. This integration aims to enhance financial modeling and decision-making processes, as well as to facilitate the integration of digital technologies in this field. Only then can the development and implementation of smart construction development advance. [ABSTRACT FROM AUTHOR]

High Friction Surface Treatments (HFSTs) are recognized for enhancing friction between tires and road surfaces, with reduced road accidents being a key benefit. Epoxy-based HFSTs, though widely used, come with challenges like compatibility issues with existing pavements, higher installation and removal costs, and reduced durability tied to substrate quality. Recently, state agencies have increasingly focused on developing asphalt-based alternative binders for HFST applications as highlighted in the National Cooperative Highway Research Program (NCHRP) RFP #NCHRP 10-145. This study introduces asphalt-based HFSTs as an alternative to traditional epoxy-based treatments. Various aggregate types were examined for friction performance and the effect of polishing cycles on asphalt-based HFST. Tests such as the British Pendulum Test (BPT), Dynamic Friction Tester (DFT), and Circular Track Meter (CTM) were conducted to assess the Coefficient of Friction (COF) and Mean Profile Depth (MPD) before and after polishing cycles. Additionally, a Life Cycle Cost Analysis (LCCA) was performed to determine the economic advantages of asphalt-based HFSTs over epoxy treatments. The goal was to develop a method to convert diverse project and material data into comparable outputs like net present value (NPV), enabling comparisons between alternatives. Results from the LCCA demonstrated that the use of specific asphalt-based binders combined with optimized aggregate gradation not only achieves performance levels comparable to traditional HFST options but also improves cost efficiency. [ABSTRACT FROM AUTHOR]

Introudction: The current CO2 levels are higher than ever in the past two million years. Forests, as one of the climate change mitigation solutions, are becoming increasingly technically feasible and cost-effective. However, limited research comprehensively considers thinning in the context of optimizing the rotation period for carbon sequestration. Methods: This study utilizes stand-level growth models and diameter distribution models to simulate the carbon balance dynamics of Larch (Larix olgensis) plantations under various thinning scenarios. The effects of different initial planting densities (N0∈{2,500, 3,333, 4,444} tree ha−1) and site class index (SCI∈[14–20] m) on the optimal forest management measures are also quantified. Results: The results reveal that the overall trend of carbon balance gradually increases and then decreases over time under the baseline scenario (3,333 tree ha−1 of N0, 16 m of SCI, 5% of discount rate, 100 CNY ton−1 C of carbon price); the carbon balances of all thinning forests were less than that of the unthinned forest before until 56th year. The optimal rotation period and net present value (NPV) increase with increasing thinning frequency and intensity. The sensitivity of NPV to thinning frequency increases with higher thinning intensities, SCI, and carbon prices. Discussion: This study further expands the scope of forest management strategies, providing optimal forest management plans for all 21 combinations of different SCIs and N0. The optimal forest management strategy in the baseline scenario is 3 thinnings, with the first thinning at 20% intensity in the 15th year, the second thinning at 30% intensity in the 18th year, and the third thinning at 30% intensity at 21 years, with a rotation period of 26 years, resulting in an NPV of 37,180 CNY ha−1. [ABSTRACT FROM AUTHOR]

In the area of reservoir engineering, the optimization of oil and gas production is a complex task involving a myriad of interconnected decision variables shaping the production system's infrastructure. Traditionally, this optimization process was centered on a single objective, such as net present value, return on investment, cumulative oil production, or cumulative water production. However, the inherent complexity of reservoir exploration necessitates a departure from this single-objective approach. Multiple conflicting production and economic indicators must now be considered to enable more precise and robust decision-making. In response to this challenge, researchers have embarked on a journey to explore field development optimization of multiple conflicting criteria, employing the formidable tools of multi-objective optimization algorithms. These algorithms delve into the intricate terrain of production strategy design, seeking to strike a delicate balance between the often-contrasting objectives. Over the years, a plethora of these algorithms have emerged, ranging from a priori methods to a posteriori approach, each offering unique insights and capabilities. This survey endeavors to encapsulate, categorize, and scrutinize these invaluable contributions to field development optimization, which grapple with the complexities of multiple conflicting objective functions. Beyond the overview of existing methodologies, we delve into the persisting challenges faced by researchers and practitioners alike. Notably, the application of multi-objective optimization techniques to production optimization is hindered by the resource-intensive nature of reservoir simulation, especially when confronted with inherent uncertainties. As a result of this survey, emerging opportunities have been identified that will serve as catalysts for pivotal research endeavors in the future. As intelligent and more efficient algorithms continue to evolve, the potential for addressing hitherto insurmountable field development optimization obstacles becomes increasingly viable. This discussion on future prospects aims to inspire critical research, guiding the way toward innovative solutions in the ever-evolving landscape of oil and gas production optimization. [ABSTRACT FROM AUTHOR]

Global optimization problems, prevalent across scientific and engineering disciplines, necessitate efficient algorithms for navigating complex, high-dimensional search spaces. Drawing inspiration from the resilient and adaptive growth strategies of moss colonies, the moss growth optimization (MGO) algorithm presents a promising biomimetic approach to these challenges. However, the original MGO can experience premature convergence and limited exploration capabilities. This paper introduces an enhanced bio-inspired algorithm, termed crisscross moss growth optimization (CCMGO), which incorporates a crisscross (CC) strategy and a dynamic grouping parameter, further emulating the biological mechanisms of spore dispersal and resource allocation in moss. By mimicking the interwoven growth patterns of moss, the CC strategy facilitates improved information exchange among population members, thereby enhancing offspring diversity and accelerating convergence. The dynamic grouping parameter, analogous to the adaptive resource allocation strategies of moss in response to environmental changes, balances exploration and exploitation for a more efficient search. Key findings from rigorous experimental evaluations using the CEC2017 benchmark suite demonstrate that CCMGO consistently outperforms nine established metaheuristic algorithms across diverse benchmark functions. Furthermore, in a real-world application to a three-channel reservoir production optimization problem, CCMGO achieves a significantly higher net present value (NPV) compared to benchmark algorithms. This successful application highlights CCMGO's potential as a robust and adaptable tool for addressing complex, real-world optimization challenges, particularly those found in resource management and other nature-inspired domains. [ABSTRACT FROM AUTHOR]

The main objective of this study was to identify the status and development opportunities and evaluate the economic viability of investments in large-scale photovoltaic installations in Southeastern Poland. The primary data sources used in the study were empirical materials from all photovoltaic installations implemented with support from the Regional Operational Program of the Lublin Voivodeship (ROP WL) for 2007–2013 (31 projects). The following indices were used to evaluate the economic efficiency of the investments studied: rate of return on investment (ROI), simple payback period (SPP), net present value of investment (NPV), internal rate of return (IRR), discounted payback period (DPBT), and averaged unit cost of electricity generation (LCOE). They were carried out for three scenarios–baseline, conservative, and optimistic–in two variants, for actual capital expenditures considering financial support used and without subsidies. It was determined that the expected lifetime of the studied investments would be 25 years. The sensitivity analysis shows that, regardless of the adopted scenario, investments in solar thermal power with the level of support that took place under the 2007–2013 financial perspective were reasonable long-term investments. In the least favorable scenario (conservative) included in the analysis, the discounted payback period ranged from 8.1 to 22 years. In the optimistic scenario, DPBT values ranged from 5.6 years to more than 15 years. The payback period (both simple and discounted) for investments with the subsidy was, on average, almost twice as fast as for investments without the subsidy, while the average unit cost of electricity generation with the subsidy was about 30% lower than without it. [ABSTRACT FROM AUTHOR]

This study examined the economic potential of thinning in pure, even-aged Norway spruce and Scots pine forests in Norway based on simulated stand dynamics using plot data from the Norwegian national forest inventory. Simulated management scenarios included fully mechanized thinning from below of varying intensity including no thinning. The economic evaluation was based on comparing the equivalent annual annuity of the unthinned scenario and the economically best-performing thinning scenario for each studied plot. The findings suggest that only late thinnings in well-stocked stands with sufficiently large trees are economically beneficial. Furthermore, to be economically superior, a thinning intervention itself had to generate enough profit, meaning that the revenue from thinning needed to sufficiently exceed the costs. Profitability of thinning scenarios varied with discount rates and timber prices and depended on whether rotation age was based on maximum net present value or maximum mean annual increment. Thinning was less often profitable in pine compared to spruce stands. This study is among the few that model stand development considering post-thinning stand structures with systematic machine trails while assessing the profitability of such thinning operations. [ABSTRACT FROM AUTHOR]

• An off-grid photovoltaic power generation energy storage refrigerator system was designed and constructed. • The system's cooling performance and off-grid operation were tested. • Daily power generation was found to be affected by irradiance, photovoltaic module cleanliness, ambient temperature, sunlight hours, and battery voltage. • Daily power generation is significantly affected by irradiance(r = 0.49) and battery voltage(r = 0.64). • The refrigerator's BCR is 1.629, LCOE is 0.495 CNY/kWh, NPV is 3,709.954 CNY, and IRR is 8.66 %. With the rapid advancement of photovoltaic and energy storage technologies, photovoltaic energy storage refrigerator systems have gained significant attention as an innovative energy solution. This paper designs and constructs an off-grid photovoltaic power generation energy storage refrigerator system, and evaluates its economic viability in practical environments. By measuring indoor temperature, refrigerator internal temperature, irradiance, and daily power generation, the paper analyzes system operating parameters such as refrigerator cooling rate and power supply mode, and studies the system's refrigeration performance, off-grid operation capability, and factors affecting daily power generation. Utilizing economic indicators such as benefit-cost ratio, levelized cost of electricity, investment dynamic payback process, net present value, and internal rate of return, the economic viability of the system is assessed. Results indicate that the system meets refrigeration performance requirements, maintaining a uniform temperature distribution and extended off-grid operation capability. Daily power generation is influenced by weather conditions, seasons, and all electrical loads in the system. In the Dalian region of China, the system demonstrates good economic viability, enabling investment recovery and profitability in a relatively short period. This system has broad market prospects in areas with abundant solar resources or high demand for refrigerator usage. [ABSTRACT FROM AUTHOR]

Since antiquity it has been seen that the wetland ecosystem not only contributes a considerable proportion of welfare to the local people in terms of food, fuel wood, timber, drinking water, irrigation water, etc., but also has immense importance in long-standing cultural practices and ecological balances. However, the domestic utilization of wetlands gets reduced when we move a step toward its conservation programs particularly in developing nations. To this end, a case study has been attempted in north Himalayan wetland in India to explore the difference in nexus between wetland conservation and livelihood dependence of local people to present an utmost importance of wetland. Survey data were collected using semi-structured questionnaires and were analyzed by employing market price method, contingent valuation approach and regression equations. The results of the study revealed that wetland yields an average direct net benefit accounts of rupees (Rs.) 32.25 thousands (US$392)/year per household from agricultural, fishing and tourism activities to the local people. Agricultural activity was found a highest preferred economic activity of local people followed by fishing on wetland. However, tourism was found an utmost income-earning activity on wetland producing least unhygienic effects. Next, the logit model results show variables, viz. household income (p < 0.05), education (p < 0.01) and willing to shift from wetland area (p < 0.05) are positively and significantly associated with the willingness to pay (WTP) for wetland conservation. It is also observed from the study results that majority (73%) of respondents were accepting the offer of contingent valuation hypothetical scenario and paying an average annual WTP of rupees (Rs.) 338 (US$4) for wetland conservation even though deriving substantial direct benefits from wetland. Therefore, the people are more enthusiastic to conserve the wetland for ecological balances and tourism purposes instead of other commercial purposes. Based on these findings of the study, it has been suggested to the concerned authorities to propose a win–win solution that either to develop a community-based conservation program or build up a constant sustainable management program for the wetland which will ensure the survival of both human societies and wetland ecosystem. [ABSTRACT FROM AUTHOR]

Many economists have demonstrated that shareholder return constraints can negatively affect investment managers' decisions. While most studies are empirical, their findings are mixed. The real options literature provides a theoretical foundation for why a simple net present value rule based on a firm's cost of capital could lead to either insufficient investment or excessive investment. This study analyzes how the pursuit of shareholder value impacts optimal investments using Tobin's Q model in perfect competition. The study demonstrates that Tobin's Q, modified by shareholder constraints, can either hinder or promote optimal investment, thereby explaining the divergent results of empirical studies on this issue. [ABSTRACT FROM AUTHOR]

Managing solid waste continues to be an environmental, technical and economic challenge, especially for developing countries. Though these countries' urban local bodies (ULBs) are moving up the waste management hierarchy, most waste is still openly dumped. One key reason for this choice is the non-accounting of (a) social costs associated with open dumping (OD) and (b) direct/indirect benefits of other options. The current study conducts a complete social cost–benefit analysis (SCBA) comparing OD to sanitary landfilling, composting, bio-methanation, incineration and gasification alternatives. The study finds that when only private costs/benefits are considered, a mix of OD and sanitary landfills is preferred; however, when external costs/benefits are factored in, the mix shifts towards alternatives like incineration and gasification. These learnings from the SCBA are then applied to Mumbai, which generates 9000 tonnes of waste daily. To determine the optimal mix for Mumbai ULB, a constrained optimization exercise is carried out considering the technical feasibility of the alternatives and the ULB's capital budget. The study finds that with the current practice of OD, the net present value (NPV) of the social costs over a 30-year horizon will be over US$ 6–9 billion. However, even if one-fifth of the ULB's capital budget is allocated towards other waste management alternatives, the mix would shift towards sophisticated technologies and the NPV of social costs would reduce to around half that amount. [ABSTRACT FROM AUTHOR]

The co-production of BHD with other renewable fuels (i.e., using a novel process involving carbon dioxide utilization to achieve the global sustainability goal) is presented. The three configurations of BHD production from refined bleached deodorized palm oil (RBDPO), including (1) the conventional BHD process with hydrogen recovery (BHD process), (2) the BHD process coupled with the Fischer–Tropsch process (BHD-FT process), and (3) the BHD process coupled with the bio-jet fuel and methanol processes (BHD-BIOJET-MEOH process) are investigated using the process model developed in Aspen Plus. The effect of the operating parameters is studied, and the condition of each process offering the highest BHD yield is proposed. Then, the pinch analysis and heat exchanger network (HEN) design of each proposed process are performed to find the highest energy-efficient configuration. The economic and environmental analysis is later performed to investigate the sustainability performance of each configuration. The conventional BHD process requires less hydrogen and consumes less energy than the others. The BHD-BIOJET-MEOH process is the most economically feasible, offering the highest net present value (NPV) of USD 7.93 million and the shortest payback period of 3 years and 1 month. However, it offers the highest carbon footprint of 0.820 kgCO2 eq./kg of BHD, and it presented the highest potential environmental impact (PEI) in all categories. [ABSTRACT FROM AUTHOR]

Integrating renewable energy sources into the power system is essential for rapid and cost-effective decarbonization. This study evaluates the potential of a wind farm by analyzing three turbine models – VESTAS, GAMESA, and W2E – with power capacities from 2.5 MW to 8 MW. The analysis focuses on Region III, characterized by wind speeds below 7.5 m/s. Using the RETScreen model, the study identifies an optimized wind-rated power (OWRP) that balances financial viability, technical performance, and capacity factors. Monte Carlo simulations and sensitivity analyses assess financial indicators such as the levelized cost of energy, net present value, and equity payback period. The framework also considers greenhouse gas (GHG) credits. Results show that turbines with 4.5 MW power, rotor diameters of 105–128 m, and hub heights of 150 m are the most feasible. The project would reduce annual CO2 emissions by 187,097 tons and avoid 82,031 tons of fossil fuel consumption, equivalent to 17,559 hectares of forest CO2 absorption or 190,915 people cutting energy use by 20%. Without GHG credits, the equity payback period is 6.2 years; with a €50/tCO2 credit, it drops to 2.7 years. These findings offer policymakers in Albania and similar low-wind regions a guide to meeting 2050 energy and climate targets. [ABSTRACT FROM AUTHOR]

It is currently essential to seek innovative solutions for sustainability and the efficient use of resources, rooted in bioeconomy principles and linked to the concepts of the circular economy. Technological innovations supporting the production of wood–plastic composites, using recycled materials, reduce the ecological footprint. The aim of the study was to present conclusions of the evaluation of the business plan concept's effectiveness and to propose applications of traditional and innovative cost calculations resulting from the implementation of technological innovations in the production of wood–plastic composites in the forest-based sector in accordance with the principles of the circular economy. Using dynamic methods for evaluating business plan net present value, profitability index, internal rate of return, and discounted payback period, positive recommendations for project rentability were identified under both realistic and pessimistic scenarios. By applying traditional markup calculation, material cost savings of EUR 3.99/m3 were quantified, representing a relative saving of over 2% compared to traditional particle board. Verification of alternative machine hour rate calculation allows for more precise allocation of overhead costs into product pricing and provides the ability to respond swiftly to changes in input parameters. The findings have practical implications for the forest-based sector, as the use of recycled plastics can reduce production costs and increase the competitiveness of production. [ABSTRACT FROM AUTHOR]

It is commonly known that buildings in hot climate contribute to a huge amount of electricity consumption mainly due to air conditioning needs. Many countries around the world are aiming to convert buildings to net zero energy buildings (NZEB). However, buildings in hot climates require varieties of active and passive measures to adapt the concepts behind NZEB. This work attempts to resolve the challenges associated with shifting school buildings to NZEB in hot arid climates. It presents an energy performance analysis that is focused on two scenarios for new and retrofitted schools. Building thermal simulation is used to assess the implications of several energy conservation measures, and different scenarios are suggested to utilize up to 80% of roof's area for the installation of Photovoltaics (PV), and on-site wind turbines. The implemented energy conservation measures show a reduction in annual energy consumption by 35% and 21% for new and retrofitted schools respectively. Discounted payback period is used to estimate the economic feasibility of the suggested scenarios. It is found that NZEB is technically feasible at highest roof area PV installations with respective discounted paybacks of 3.55 and 5.54 years for the new and retrofitted schools. However, adding wind-turbines can delay the breakeven year of investments needed to achieve NZEB. The estimated savings in net present value (NPV) are 3273 and 4284 thousand US dollars for the retrofitted and new schools respectively, and each school's roof can generate 40.63 GWh in 25 years and avoid 29.23 kilotons of CO2. [ABSTRACT FROM AUTHOR]

The North American Model of Wildlife Conservation calls for the treatment of wildlife as a public resource and entrusts states as the primary management authority. As such and dating back to colonial law, states provide their residents with privileged access to hunting and fishing opportunities in the form of higher quotas and lower license prices. The implied value of these resident harvest privileges to state decision-makers is revealed in the tradeoff between foregone revenue-increasing opportunities from nonresident consumers and the preservation of access for resident consumers. We present the first natural capital valuation of the forgone welfare of such policies by recovering net present values for Wyoming's iconic Jackson elk herd. Herd population dynamics and the legal and institutional context surrounding management and hunting behavior reveal three key findings: (i) the net present value of the Jackson herd is $207.5 million of which 76% benefits the State of Wyoming, (ii) resident hunting privileges result in a welfare loss of $11.8 million and (iii) a reoccurring policy proposal to increase "state protectionism of elk" by changing resident hunting quotas from 80 to 90% would forego an additional $7.8 million in welfare, but would increase the herd's value to the state. While regional in its application, our use of policy simulations provides a generalizable approach to assessing the distributional impacts of current, not necessarily optimal, resource management tendencies. [ABSTRACT FROM AUTHOR]

The article "Long-Term Product Forecasting in Pharmaceuticals" by Robert F. Siegmund discusses the structured approach to pharmaceutical forecasting, focusing on patient-based models to derive sales projections. It distinguishes between different types of forecasts, such as volume and value forecasts, and emphasizes the importance of factors like regulatory approvals and clinical trial outcomes. Advanced techniques like scenario planning and Monte Carlo simulations are recommended to manage uncertainty in forecasting. The article also highlights the impact of black swan events on forecasting and decision-making in the pharmaceutical industry. [Extracted from the article]

Production of hydrogen from renewable sources is gaining popularity to reduce our dependency on non-renewable fossil fuels to meet growing hydrogen demand. However, despite the great prospect of production of hydrogen from sustainable sources such as lignocellulosic biomass via supercritical water gasification (SCWG), it has not been commercialized at a large industrial scale. This is due to the lack of detailed economic analysis of SCWG of lignocellulosic biomass, owing to the complexity of the SCWG process and the heterogeneous nature of biomass. Therefore, to address this knowledge gap, in this study, a detailed technoeconomic analysis (TEA) of a conceptual SCWG pilot having the capacity to process 200 tons/day of canola straw for the production of green hydrogen was conducted. Mass and energy balance of conceptual pilot was performed using Aspen Plus ® simulation by utilizing experimental data and hydrogen yield of 41.62 mmol/g was obtained at optimized reaction conditions of 500 °C, 23 MPa, and 10 wt%. Economic analysis based on calculated mass and energy balance was performed using SuperPro software. Cash flow analysis for capital expenses (CAPEX) of 81 Million USD showed a high internal rate of return (IRR) of 38.9% and an undiscounted net present value (NPV) of 548 million USD. A minimum selling price (MSP) of 3.38 USD/kg H 2 for produced hydrogen was estimated, which is lower than other renewable hydrogen production processes and comparable to non-renewable hydrogen production technologies. A high positive IRR and NPV, while a lower MSP showed that despite having a low technological readiness level (TRL) of 4, SCWG of lignocellulosic biomass is a technically feasible and economically viable process for the production of hydrogen. Furthermore, sensitivity analysis also revealed that capital expenses (CAPEX) and canola straw price had the highest influence on net present value (NPV) and MSP. However, overall NPV and MSP were highly stable to changes in parameters highlighting the robustness of the economic analysis. • Technoeconomic analysis of hydrothermal gasification of 200 ton of canola straw/day. • Mass and energy balance of plant calculated by thermodynamic simulation in Aspen. • Minimum selling price of 3.38 USD/kg H 2 was estimated for produced hydrogen. • Selling price was most sensitive to capital expenditure and canola straw cost. • Cash flow analysis showed profitability with high internal rate of return of 38.9%. [ABSTRACT FROM AUTHOR]

The use of CO2 to improve oil recovery has the disadvantage of reduced sweep efficiency due to the large difference in density and viscosity between oil and CO2. Overcoming these drawbacks, the use of dimethyl ether (DME) is known to be more effective than CO2 in improving oil recovery. In this study, a CO2-DME mixed solvent, is thoroughly investigated by developing a compositional model. The oil recovery of a CO2-DME mixed solvent has been examined in terms of sweep efficiency and displacement efficiency by comparing CO2-water-alternating-gas (WAG) and CO2-DME WAG. According to the results from compositional simulation, the highest DME content investigated resulted in a 66.4% lower viscous gravity number and a 26.6% increase in sweep efficiency compared to CO2 WAG. Minimum miscible pressure (MMP) and interfacial tension (IFT) were reduced by 30.1 and 97.5%, respectively, significantly improving the mobility of the oil. As a result, the amount of oil remaining in the reservoir decreased by 40.7%, and oil recovery increased by 31%. An economic evaluation considering optimized injection design and reuse of recovered DME showed a 13% improvement in net present value (NPV) of CO2-DME WAG over CO2 WAG. [ABSTRACT FROM AUTHOR]

To solve the problem that indiscriminate subsidy policy is difficult to effectively exert an incentive effect on the investment behavior of enterprises, this paper puts forward a type of differentiated subsidy considering resource conditions, which consists of a basic security subsidy and a variable excitation subsidy. First, on the premise of guaranteeing the basic rate of return of enterprises, the net present value formula is used to compute the basic allowance. Then, according to the principal-agent theory, the revenue functions of government and enterprises are constructed, and the calculation model of the incentive scheme can be obtained by quantifying the correlation coefficients between resource conditions and social benefits. The case application shows that the Fuling block requires a significantly smaller amount of subsidy than the Weiyuan block due to its superior resources and development conditions, which verifies the necessity of considering regional differences in the design of shale gas development subsidies. This differentiated subsidy model can improve the efficiency of the use of financial funds while taking into account the fairness of policy implementation in different regions. [ABSTRACT FROM AUTHOR]

Hydrogen represents today a necessary alternative to fossil fuels to limit the greenhouse gas effect due to the CO 2 emissions. In this work, a plant configuration able to get pure H 2 and concentrated CO (about 94%) from a syngas mixture is proposed and simulated by coupling a selective membrane unit and a water absorption column. In addition, an economic assessment on the simulated plant is carried out to estimate the feasibility of this process in terms of economic potential, studying its dependence on several parameters, such as raw material price, membrane cost, membrane feed pressure, column temperature and feed flow rate. Separation performance is improved by the higher feed membrane pressure (greater H 2 recovery and CO purity), whereas the increment of the column temperature especially affects the CO recovery. Hence, the economic potential presents a maximum with pressure and temperature (e.g., about 246ꞏ103 $/y at 40 bar of feed membrane pressure and about 282ꞏ103 $/y at 50 °C of column temperature), due to the balance between the higher compression/solvent cost and the increment of H 2 or CO recovery. In addition, the simulated plant shows a positive economic potential in a wide range of syngas price (e.g., from 0.126 to 0.25 $/Nm3), being also not affected significantly by the cost of the palladium-based membrane module. A bigger plant size (i.e., feed flow rate from 10 to 100 kmol/h) can lead to a twelve times greater economic potential (from about 242ꞏ103 to about 2954ꞏ103 $/y at 30 bar), reducing the H 2 purification cost and making the net present value positive. [Display omitted] • Pure H 2 and CO from syngas by membrane separation and water absorption. • Economic potential dependence on the operating conditions, syngas price, membrane cost. • A maximum economic potential of about 246ꞏ103 $/y at a membrane pressure of 40 bar. • A maximum economic potential of about 282ꞏ103 $/y at a column temperature of 50 °C. • A strong increase of the economic potential with feed flow rate (up to 12 times). [ABSTRACT FROM AUTHOR]

Introduction: This paper introduces a framework for assessing the economic performance of agrivoltaic systems (AVS) in vineyards. The study aims to classify factors influencing the profitability of integrating photovoltaic (PV) systems with viticultural practices, emphasizing potential synergistic benefits. Focused on the geographic and climatic conditions of Geisenheim, Germany—home to the first AVS installation in viticulture in Germany—the framework highlights the need to explore economic and operational parameters to assess AVS feasibility. Methods: The study operationalized its framework by simulating various scenarios based on key variables such as capital expenditures (CAPEX), operational expenditures (OPEX), and revenue streams from grape and energy production. Key factors considered included solar radiation, panel transparency, and regulatory impacts. Scenarios evaluated included: i) Configurations with fully opaque and semi-transparent PV modules. Ii) Adjustments for full mechanization of viticulture practices. Iii) Self-consumption of the produced energy. The framework employed these simulations to evaluate economic outcomes and identify profitability determinants under different conditions. Results: Findings indicate that under current conditions in Germany, AVS systems are not economically viable for widespread adoption. Key results include: Economic Outcomes : High initial costs (CAPEX) and insufficient revenue from combined grape and energy production lead to negative net present values over a 20-year period across all simulated scenarios. Profitability Determinants : CAPEX and energy prices emerged as critical factors, while viticulture-related costs and revenues had a minor impact on overall profitability. Potential Improvements : Scenarios incorporating multiple positive changes—such as premium wine pricing, higher feed-in tariffs, and increased self-consumption of energy—demonstrated potential for economic feasibility. Discussion: The study underscores that high CAPEX and low revenues from grape and energy production are the main barriers to AVS profitability. For AVS systems to achieve economic sustainability, substantial reductions in installation costs, increases in energy prices, or technological advances in efficiency are required. Promising configurations combining multiple favorable changes suggest a pathway toward economic feasibility but highlight the need for further development and innovation. The framework provides valuable guidance for future research and investment strategies, emphasizing the importance of: i) Long-term Trials: To evaluate viticultural impacts and synergistic benefits. Ii) Dynamic Models: Incorporating evolving revenue streams, cost structures, and regulatory impacts. iii) Broad Assessments: Exploring the environmental and social benefits of AVS alongside economic performance. Continuous updates to the framework will ensure its relevance, reflecting advancements in PV technology, viticultural practices, and policy environments. This approach will help bridge the gap between renewable energy and sustainable agriculture. [ABSTRACT FROM AUTHOR]

Ceramic Matrix Composites (CMCs), specifically SiC/SiC composites, represent a significant innovation in aerospace material technology, offering superior performance over traditional nickel-based superalloys in high-temperature turbine blade applications. This study presents a novel techno-economic assessment, filling a critical gap in the literature by directly comparing the economic and technical viability of CMCs versus superalloys. Unlike previous studies, which primarily focus on technical performance or cost analysis independently, this work integrates both aspects, providing a holistic comparison across key economic metrics, including acquisition, machining, maintenance, and recycling costs. The results demonstrate that SiC/SiC blades offer a 15–20% higher Net Present Value (NPV) and a 17% greater Internal Rate of Return (IRR) over a 20-year lifecycle than superalloys. Despite higher initial costs, CMCs achieve an estimated 2 to 3 years reduction in payback period, mainly due to their superior thermal and creep resistance, leading to fewer maintenance interventions and longer operational lifetimes. Although machining costs for CMCs are higher, these are more than offset by the long-term savings achieved through improved fuel efficiency and lower maintenance costs. A comprehensive sensitivity analysis, incorporating fluctuations in discount rates and material costs, further validates the economic robustness of CMCs in various operational scenarios. This study is the first to compare CMCs and superalloys, offering new insights into the financial implications of material selection in aerospace manufacturing. The findings present critical engineering recommendations that empower aerospace manufacturers and decision-makers to optimise material selection for improved efficiency and cost-effectiveness in high-performance turbine applications. [ABSTRACT FROM AUTHOR]

Development with the expansion of electronic devices, increased electricity consumption, and supplying the required power are some challenges involving different countries. Iran is also currently consuming in its industries that to supply electricity, it is necessary to adjust the program of various blackouts, hence the stoppage of the production of industries and mines has caused significant damage. This paper presents a comprehensive feasibility study for the construction of a 10-MW grid-connected photovoltaic (PV) power plant aimed at mitigating energy deficits in Iran's iron ore mining sector, particularly during blackout periods. Utilizing HOMER software for technical simulation, the proposed solar plant is projected to generate approximately 16 million kWh annually, with 2 million kWh available during shutdowns. Financial analysis conducted through CAMFAR software indicates a payback period of 8.6 years, an internal rate of return (IRR) of 12.67%, and a net present value of $3.45 million, underscoring the project's economic viability. The plant's capacity to compensate for the production of 66,750 tons of iron concentrate during outages underscores its potential for significant financial benefits. [ABSTRACT FROM AUTHOR]

Korea is making efforts to reduce carbon emissions from buildings and, as part of this initiative, the government is promoting the expansion of modular housing. This study analyzed the feasibility of achieving zero-energy certification and the economic viability of applying photovoltaic (PV) systems to modular housing in Korea. Energy consumption and self-sufficiency were calculated for low-rise (4 floors), mid-rise (13 floors), and high-rise (30 floors) buildings. Economic viability was assessed according to the payback period, net present value (NPV), and benefit–cost ratio (B/C ratio). Construction costs of modular buildings are higher than those of reinforced concrete (RC) buildings, and when only PV systems are applied, it is not possible to achieve a high grade in high-rise buildings. The results indicate that economic feasibility is lacking across all building heights, leading to the conclusion that further research on cost reduction and expanded government support are necessary. This study presents a sustainable building model for Korea that is expected to contribute to future policy decisions. [ABSTRACT FROM AUTHOR]