Operational Expenditure Research Articles

Life cycle cost analysis in investment projects – examination of case studies and risk mitigation with Monte Carlo simulation

This work focuses on life cycle cost (LCC) analysis in the German natural gas infrastructure and recommends strategies to mitigate the uncertainties and risks involved using Monte Carlo simulation (MCS). It deals with the impact of input data and predicting the future development of input data on the results of the LCC analysis and discusses MCS for risk mitigation. Seven case studies for investments in Germany’s natural gas infrastructure are analyzed. In addition to the executed case studies, a case study from a scientific journal is included. The case studies were conducted between 2005 and 2015. Evaluation with real historical input data shows that the results of an LCC analysis depend on the reliability of input data and predictions on their development. The retrospective view shows that the best options are not always identified. Therefore, the results need to be validated using risk-mitigation methods, such as MCS. The executed case studies reflect the opinions of experts. This work shows how risk is mitigated through MCS while focusing on LCC analysis in the German natural gas infrastructure; however, the proposed risk mitigation with MCS can be adopted for other investment projects comprising capital expenditure (CAPEX) and operational expenditure (OPEX), for example, in construction, machines and other fields.

Driving Forces of Strategic Outsourcing in Telecommunication Companies in Tanzania

Abstract This article aims to evaluate the driving forces of outsourcing strategies on the organizational performance of mobile network operators in mainland Tanzania. The objectives are to identify the driving forces of outsourcing and determine the challenges of outsourcing in telecommunication companies. The article adopted a descriptive cross-sectional survey. The selection of mobile companies is based on high market share and operation period. Findings show that customer needs for high-quality services, high-rated change in service, reduction of operational expenditure, and accessing the world’s capability are among the major driving forces for outsourcing. Dependability, loss of security, hidden costs, and selection of competent partners to mention a few are the challenges faced by telecom companies. It is noted that outsourcing enables network operators to advance their organizational performance in terms of operating cost, productivity, profitability, and market share. However, customer satisfaction suffers due to the inconsistency of the quality of service offered. Therefore, it is advised that mobile operators closely monitor outsourcing service providers to ensure that agreed service levels are met, thereby, safeguarding the reputation of the company to customers.

The prospect of floating photovoltaic in clean energy provision and net-zero-emissions

AbstractThis study emphasizes the critical role of renewable energy in addressing climate change challenges, particularly in reducing greenhouse gas emissions. It highlights the central importance of solar photovoltaic systems. While recognizing South Africa’s progress in renewable energy deployment, the study notes that substantial efforts are still needed to meet the country’s renewable energy targets. The study’s primary aim is to enhance the understanding and deployment of solar photovoltaic systems by critically examining the photovoltaic potential and performance of different sites. To achieve this, two scenarios—land photovoltaic and floating photovoltaic systems—were considered, focusing on hypothetical 10 MWp-installed capacity systems. The results indicate that the 10-MWp land photovoltaic system has a global tilted irradiance of 2184.7 kWh/m2, an annual total output of 18 GWh, and an average yearly performance ratio of 81%. The economic parameters for the land photovoltaic system include a capital expenditure of $9.0 million, an operational expenditure of $157,500 annually, and a levelised cost of energy of $0.04089/kWh. In contrast, the 10-MWp floating photovoltaic system reports a Global Tilted Irradiance of 1797 kWh/m2, an annual total output of 16 GWh, and a performance ratio of 76%. The economic parameters for the floating photovoltaic system include a capital expenditure of $10.6 million, an operational expenditure of $176,250 annually, and a levelised cost of energy of $0.04936/kWh. Both scenarios’ econo-technical parameters fall within acceptable ranges. However, the land photovoltaic system shows better performance, indicating some efficiency loss in the floating photovoltaic system possibly due to harsher offshore conditions. Based on the data from the reports, the study concludes that the econo-technical feasibility of floating photovoltaic in the Western Cape Province of South Africa is high. Graphical abstract

Analisis Kinerja Anggaran Belanja Pada PTN BLU X Tahun Anggaran 2021-2023

In managing the budget, it is crucial to conduct budget performance measurement or analysis, which involves assessing and measuring the implementation or realization of the budget. This study presents an original analysis of PTN X, a State University with BLU (Public Service Agency) status under the Ministry of Education, Culture, Research, and Technology. The BLU status provides flexibility in budget management. Therefore, the purpose of this research is to analyze the budget performance of PTN X as a basis for evaluation to improve quality. In this study, the authors use a descriptive quantitative method, with the research object being the budget performance of PTN X from 2021 to 2023. The data analysis techniques employed include several expenditure analysis calculations, namely 1) Variance Analysis, 2) Growth Analysis, 3) Compatibility Analysis, and 4) Efficiency Analysis. The Financial Expenditure Performance of PTN X, as seen from the Variance Analysis, falls into the good category or Favourable Variance. From the Growth Analysis perspective, there was no expenditure growth observed in 2022; however, there was expenditure growth in 2023. The Compatibility Analysis revealed an imbalance between operational and capital expenditures in 2021. In contrast, in 2022 and 2023, the balance between operational and capital expenditures can be considered stable. From the Expenditure Efficiency Analysis, it was found that the budget management of PTN X was inefficient during the years 2021-2023.

The Finance of Cybersecurity: Quantitative Modeling of Investment Decisions and Net Present Value

Despite the growing literature on cybersecurity investment, significant gaps remain unaddressed. First, the existing literature does not differentiate between cybersecurity expenditures, namely investment versus spending, despite the differences in their financial treatments. Second, the literature predominantly employs economic and risk-based models, in which the incorporation of financial parameters is limited. Third, the literature focuses on quantifying market (stock) loss of cyberattacks or conducting a cost-benefit analysis of cybersecurity investments but has yet to bridge these two areas. Thus, our objective is to introduce a new financial model, the Alpha Model, that addresses these gaps. We first provide distinctions between cybersecurity investment (capital expenditure) and spending (operational expenditure). Grounded in Relative Valuation Models and Optimal Capital Structure Theory, we quantify the upper-bound of optimal cybersecurity investment by utilizing book and market values of equity and debt. We also demonstrate that the Net Present Values (NPV) of cybersecurity investment is considerably lower than its book value by incorporating financial parameters of equity and debt financing, inflation-adjusted capital cost, and tax credits of depreciation and interest. To validate our model, we empirically test it by using data from the S&P500 index during 2018–2023. We offer practical implications to key stakeholders, including: (1) industry executives to financially quantify cybersecurity investments and ascertain their actual NPVs, individually and collaboratively with supply chain partners; (2) cybersecurity solution providers to promote business investments in cybersecurity; and (3) insurance providers to price premiums with higher NPVs than the corresponding investments. We also offer several avenues for further research.

Techno-economic analysis of biocrude, biogas, and fertilizer production from microalgae Coelastrella striolata cultivated in agroindustrial wastewater

Coelastrella microalgae have gained attention due to their robustness, high lipid content, effective bioremediation agent, and ability to thrive in diverse environmental conditions. The objective of this study was to evaluate the economic feasibility of an integrated biorefinery of the unique original Coelastrella striolata var. multistriata strain 047 applied in agro-industrial wastewater, flue gases, and excess energy on a 1.2 ha open raceway pond (ORP). This study consists of three scenarios: (1) biocrude only (BO); (2) biocrude and biogas (BB); and (3) biocrude, biogas, and fertilizer (BBF). The findings indicated that the BB and BBF scenarios enhanced the financial feasibility and potential profitability of investment. This is reflected in the economic feasibility indicators for the BB scenario over a project lifetime of 20 years, which include a net present value (NPV) of $4,757,082, an internal rate of return (IRR) of 25.6%, a profitability index (PI) of 2.77, and a payback period of 3.75 years. Similarly, in the BBF scenario, financial viability is demonstrated with an NPV of $4,714,418, an IRR of 25.2%, a PI of 2.73, and a payback period of 3.79 years. Operational expenditures were identified as the most sensitive aspect of this study, particularly in the hydrothermal liquefaction (HTL) process for biocrude production. The utilization of effluent and excess energy from palm oil mill (POM) reduced the operational costs for energy and nutrients by up to 69% compared to the baseline, where palm oil mill effluent (POME) and excess energy were not utilized. Additionally, to achieve optimal results in the BO scenario, increasing the concentration of Coelastrella striolata var. multistriata strain 047 in POME proved to be the most effective approach for increasing biocrude oil production, reducing costs, and increasing economic sustainability.

Drilling Automation Serves as Engine of Change for Risk Prevention Offshore

_ This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper OTC 35137, “Drilling Automation: An Engine of Change for Risk Prevention Offshore,” by Brennan Goodkey, SPE, Andrew Fabo, and Francois Le Buhan, SLB, et al. The paper has not been peer reviewed. Copyright 2024 Offshore Technology Conference. _ This paper delves into the evolving landscape of drilling automation, emphasizing the imperative for these systems to go beyond novelty and deliver quantifiable financial value. The complete paper presents an examination of several offshore drilling operations that exemplify the successful implementation of a closed-loop drilling-automation solution and the positive effect these technologies can have on the bottom line. Introduction In the dynamic landscape of drilling technologies, the conventional discourse on rig mechanization, robotics, and drilling automation is no longer a new topic, having nearly a decade of active discussion, development, and deployment. However, these systems, despite their longstanding presence, are still working toward substantiating their anticipated value. To navigate this challenge successfully, a clear understanding of where and how exactly the deployed solution will deliver value is required. The criteria of success inevitably will vary based on the customer, region, and objective. One of the clearest examples is obvious in the dichotomy between the priorities of high-volume drilling in onshore operations compared with offshore drilling. While the overarching goal of automation remains consistent—maintain safety while maximizing production and minimizing operational expenditures—the path to delivery in these spaces looks quite different. Offshore drilling introduces a myriad of complexities and must prioritize not only efficiency but also risk reduction and the minimization of nonproductive time. The complete paper examines the collaborative journey of several oil and gas organizations to deploy and improve a drilling-automation system aimed at the priorities and challenges of offshore drilling. Definitions The authors offer the following definitions to delineate scope as they describe an integrated system that combines domain drilling automation, rig-floor mechanization, and directional-drilling automation into a cohesive and comprehensive solution: - Domain Drilling Automation—This refers to the process of leveraging sensor data to interpret downhole conditions and react with the appropriate domain response, mimicking an experienced driller’s expertise with high accuracy and precision. - Rig-Floor Mechanization—This is the implementation of automated technologies and robotic systems on the rig floor to limit manual human involvement in tasks situated within the hazardous red zone. - Directional-Drilling Automation—This term refers to the use of automated systems and technologies to control and navigate precisely the trajectory of a drilling borehole, enhancing accuracy and efficiency in achieving specific wellbore paths and target zones. - Planning Drilling Automation—The use of advanced technologies and automated systems during office-based well planning is leveraged to optimize resources, enabling precise and efficient decision-making for the entire drilling process. - Real-Time-Monitoring Drilling Automation—The use of advanced automation technologies can monitor and analyze drilling operations continuously in real time, providing instantaneous feedback and adjustments to optimize performance, efficiency, and safety.

Analisis Kondisi Keuangan Pemerintah Kota Sibolga Tahun 2018-2022

This research was aimed to know financial condition of government Sibolga for the years 2018-2022 from efficiency of PAD ratio, effectiveness of PAD ratio, expenditure compatibility ratio and Financial Dependency Ratio. The research used is analitical descriptive. The data collection techniques used in this research were field research and library research. Descriptive and ratio analysis was used to appraise efficiency of PAD ratio, effectiveness of PAD ratio, , expenditure compatibility ratio and Financial Dependency Ratio. The result of this research pointed that (1) efficiency of PAD ratio of Sibolga for each year was 1,59% in average which mean efficiency of PAD was already efficient. (2) The Government of Sibolga is still less effective in managing PAD with an average effectiveness ratio of 76.20%. (3) the highest ratio results from operating expenditures is 85,89% in 2021 and the lowest ratio in 2018 is 77,58%. The highest ratio of capital expenditures to the total expenditure is 22,39% in 2018 and the lowest ratio in 2019 is 14,04%. The Government of Sibolga still prioritizes operational expenditure compared to capital expenditure.(4) Financial Dependency Ratio of Sibolga government during 2018-2022 is 83.88% categorized very high, this condition shows the dependency level of Sibolga Goeverment is very high to the central government.

Popularity-Aware Service Provisioning Framework in Cloud Environment

To balance the tradeoff between quality of service (QoS) and operating expenditure (OPEX), the service provider should request the appropriate amount of resources to the cloud operator based on the estimated variation of service requests. This paper proposes a popularity-aware service provisioning framework (PASPF), which leverages the network data analytics function (NWDAF) to obtain analytics on service popularity variations. These analytics estimate the congestion level and list of top services contributing most of the traffic change. Based on the analytics, PASPF enables the service provider to request the appropriate amount of resources for each service for the next time period to the cloud operator. To minimize the OPEX of the service provider while keeping the average response time of the services below their requirements, we formulate a constrained Markov decision process (CMDP) problem. The optimal stochastic policy can be obtained by converting the CMDP model into a linear programming (LP) model. Evaluation results demonstrate that the PASPF can achieve less than 50% OPEX of the service provider compared to a popularity-non-aware scheme while keeping the average response time of the services below the requirement.

Analysis of the Financial Performance of the Jambi City Government Using Variance Analysis for the 2020-2022 Fiscal Year

This research aims to evaluate the Financial Performance of the Jambi City Government through Variance Analysis for the 2020-2022 budget year. This research uses a qualitative descriptive approach by utilizing secondary data originating from the Jambi City Revenue and Expenditure Budget Realization Report for the same period. The findings show that the Financial Performance of the Jambi City Government as assessed through Income Variance Analysis is classified as Poor, Income Growth is identified as positive, the Degree of Decentralization is classified as Sufficient, the Regional Financial Dependency Ratio is classified as Very High, the Regional Financial Independence Ratio is classified as Low, the PAD Effectiveness Ratio is considered to be Fairly Effective. In terms of Performance Expenditure Variance Analysis, it is rated as Good, Operational Expenditure Analysis is rated as Fairly Good, Capital Expenditure Analysis is also rated as Fairly Good, and the Regional Expenditure Efficiency Ratio is classified as Efficient

Dynamics of bio-based carbon dioxide removal in Germany

Bio-based carbon dioxide removal encompasses a range of (1) natural sink enhancement concepts in agriculture and on organic soils including peatlands, and in forestry, (2) bio-based building materials, and (3) bioenergy production with CO2 capture and storage (BECCS). A common database on these concepts is crucial for their consideration in strategies and implementation. In this study, we analyse standardised factsheets on these concepts. We find different dynamics of deployment until 2045: for CO2 removal rates from the atmosphere, natural sink enhancement concepts are characterised by gradually increasing rates, followed by a saturation and potentially a decrease after few decades; forest-related measures ramp up slowly and for construction projects and bioenergy plants, annually constant removal rates are assumed during operation which drop to zero afterwards. The expenses for removing 1 t CO2 from the atmosphere were found to be between 8 and 520 € t CO2−1, which arises from high divergence both in capital and operational expenditures among the concepts. This high variability of expenses seems to suggest the more cost-effective concepts should be implemented first. However, aspects from economics, resource base and environmental impacts to social and political implications for Germany need to be considered for developing implementation strategies. All concepts investigated could be deployed on scales to significantly contribute to the German climate neutrality target.

Blockchain Technology Application and Potential in the Global Securities Trading Market

With the rapid development of financial technology, blockchain technology is gradually permeating the global securities trading market. This paper delves into the current status of blockchain technology applications in this field, covering key aspects such as trade settlement and clearing, securities issuance and trading, identity verification, and compliance management. Through detailed case studies, it powerfully demonstrates its significant reduction in settlement cycles and intermediate links, thereby improving trade efficiency; its substantial reduction in operational costs and additional expenditures due to human errors, thereby lowering costs; and its effective resistance to cyber-attacks through data encryption and tamper-proof characteristics, thereby enhancing security. At the same time, it explores the positive role of blockchain technology in improving market trust by offering transparent transaction records and reducing information asymmetry. The paper further analyzes the challenges faced by blockchain technology in the global securities trading market, including issues with technology maturity such as performance scaling and interoperability, regulatory and compliance issues such as incomplete legal frameworks and policy uncertainties, industry acceptance issues such as conservative attitudes from traditional institutions and insufficient technology popularization education, and security risks such as emerging vulnerabilities and private key management risks. On this basis, it provides a forward-looking outlook on the potential and development trends of blockchain technology in the global securities trading market in the future, including integration trends with other emerging technologies, its role in promoting cross-border transactions and financial market integration, the possibility of innovative financial products and services, and the resulting changes in market patterns. In summary, this paper provides a comprehensive and systematic study of the current status, advantages, challenges, and future development of blockchain technology in the global securities trading market, offering valuable references and insights for further development in this field.

The Impact of LIDAR‐Assisted Pitch Control on Floating Offshore Wind Operational Expenditure

The Impact of LIDAR‐Assisted Pitch Control on Floating Offshore Wind Operational Expenditure

Optimized removal of silica during manure treatment by electrocoagulation-flotation (EC-F) in view of fouling prevention of reverse osmosis membranes

Reverse osmosis (RO) membrane fouling threatens the performance of manure treatment. In this regard, silica is considered one of the most challenging inorganic foulants. Removing silica fouling from RO membranes is difficult, ultimately leading to performance deterioration, including reduced permeability and premature membrane failure. This study examines the removal of silica during manure treatment using a novel tubular electrocoagulation-flotation (EC-F) reactor with an Al electrode. The EC-F was positioned between an ultrafiltration and a RO membrane filtration system. The operational parameters—current density, electrolysis residence time, and initial pH—were optimized for maximum silica removal efficiency and minimum operational cost. At the optimum conditions (pH of 8.2, current density of 160 A/m2 and electrolysis residence time of 23 s), 88 % of silica (initial concentration of 104 mg/L) was removed. Subsequent membrane fouling assessment revealed that EC-F pretreatment decreased the fouling potential by 28 % (from 7.11 × 1016 to 5.10 × 1016 Pa·s/m2·t), indicating efficient foulant removal. SEM-EDX analysis of the membrane confirmed the lack of scale formation when using EC-F pretreated manure as a feed stream. This study demonstrates that the use of innovative EC-F pretreatment significantly reduces the operational expenditure (1.75 €/m3) compared to prior EC-F research for silica removal from manure, thereby reducing the fouling of RO membranes.

Sizing a Renewable-Based Microgrid to Supply an Electric Vehicle Charging Station: A Design and Modelling Approach

In this paper, an optimisation framework is presented for planning a stand-alone microgrid for supplying EV charging (EVC) stations as a design and modelling approach for the FEVER (future electric vehicle energy networks supporting renewables) project. The main problem of the microgrid capacity sizing is making a compromise between the planning cost and providing the EV charging load with a renewable generation-based system. Hence, obtaining the optimal capacity for the microgrid components in order to acquire the desired level of reliability at minimum cost can be challenging. The proposed planning scheme specifies the size of the renewable generation and battery energy storage systems not only to maintain the generation–load balance but also to minimise the capital cost (CAPEX) and operational expenditures (OPEX). To study the impact of renewable generation and EV charging uncertainties, the information gap decision theory (IGDT) is used to include risk-averse (RA) and opportunity-seeking (OS) strategies in the planning optimisation framework. The simulations indicate that the planning scheme can acquire the global optimal solution for the capacity of each element and for a certain level of reliability or obtain the global optimal level of reliability in addition to the capacities to maximise the net present value (NPV) of the system. The total planning cost changes in the range of GBP 79,773 to GBP 131,428 when the expected energy not supplied (EENS) changes in the interval of 10 to 1%. The optimiser plans PV generation systems in the interval of 50 to 63 kW and battery energy storage system in the interval of 130 to 280 kWh and with trivial capacities of wind turbine generation. The results also show that by increasing the total cost according to an uncertainty budget, the uncertainties caused by EV charging load and PV generation can be managed according to a robustness radius. Furthermore, by adopting an opportunity-seeking strategy, the total planning cost can be decreased proportional to the variations in these uncertain parameters within an opportuneness radius.

Life-Cycle Gradient-Based Production Optimization Including Well-Shutoff Option with Least-Squares Support Vector Regression

Summary In this work, we focus on well-shutoff/well-control optimization, which enables shutting off a production well or injection well to be part of the well-control optimization within a net present value (NPV) formulation that includes the operation expenditures (OPEX) if the well is not economical to produce or inject. For this purpose, we formulate an objective function for the NPV by introducing a production time fraction as the design variable to shut off a production well over its total production life, divided into a fixed number of cycles. Unlike the previous studies, we use a shutoff period within each cycle instead of shutting it off with a bottomhole pressure (BHP) control, where the BHPs for each producer are part of the optimization variables. When BHPs are considered control optimization variables with an NPV having OPEX, the NPV could be discontinuous for BHPs. To avoid this problem, we built a continuously differentiable proxy function for NPV using least-square support vector regression (LS-SVR). We use linear equality constraints so that the sums of the lengths of the cycles at each producer and injector are equal to the life of the production. Thus, we do not need to truncate the size of the last cycle, as in the previous studies, which may lead to suboptimal solutions. We use a simulator-based optimization method with stochastic simplex approximate gradient (StoSAG) and a machine learning-based (LS-SVR) optimization method to solve such an optimization problem. We update the LS-SVR proxy during optimization so that the updated proxy remains predictive toward promising regions of search space during the optimization. We compare the performance of the proposed LS-SVR-based iterative sampling refinement (ISR) method with the StoSAG-based and the finite difference (FD)-based optimization methods. To demonstrate the applicability of our proposed methodologies, we consider a synthetic example of a waterflooding process in a tight oil reservoir with two water injectors and four producers. Results show that the LS-SVR-based optimization method is at least three to seven times more computationally efficient than the StoSAG-based optimization method using a high-fidelity numerical simulator. However, we observe that the size and sampling of the training data, as well as the selection of bound constraints for the well controls, influence the performance of the LS-SVR-based optimization method. Designing multiple shutoffs and making cycle lengths unknown are found to be ineffective compared to single shutoff cases, as they yield lower NPVs.

Sex Differences in Profile and In-Hospital Death for Acute Stroke in Chile: Data From a Nationwide Hospital Registry.

Knowledge of local contextual sex differences in the profile and outcome for stroke can improve service delivery. We aimed to determine sex differences in the profile of patients with acute stroke and their associations with in-hospital death in the national hospital database of Chile. We present a retrospective cohort based on the analysis of the 2019 Chilean database of Diagnosis-Related Groups, which represents 70% of the operational expenditure of the public health system. Random-effects multiple logistic regression models were used to determine independent associations of acute stroke (defined by main diagnosis International Classification of Diseases, Tenth Revision [ICD-10] codes) and in-hospital death, and reported with odds ratios (ORs) and 95% CIs. Of 1 048 575 hospital discharges, 15 535 were for patients with acute stroke (7074 [45.5%] in women), and 2438 (15.6%) of them died during hospitalization. Differences by sex in sociodemographic and clinical characteristics were identified for stroke and main subtypes. After fully adjusted model, women with ischemic stroke had lower in-hospital death (OR, 0.79 [95% CI, 0.69-0.91]) compared with men; other independent predictors included age per year increase (OR, 1.03 [95% CI, 1.03-1.04]), chronic kidney disease (OR, 1.47 [95% CI, 1.20-1.80]), atrial fibrillation (OR, 1.50 [95% CI, 1.26-1.80]), and other risk factors. Conversely, for intracerebral hemorrhage, women had a higher in-hospital mortality rate than men (OR, 1.19 [95% CI, 1.02-1.40]); other independent predictors included age per year increase (OR, 1.009 [95% CI, 1.003-1.01]), chronic kidney disease (OR, 1.55 [95% CI, 1.23-1.97]), oral anticoagulant use (OR, 1.88 [95% CI, 1.37-2.58]), and other risk factors. Sex differences in characteristics and in-hospital death of hospitalized patients exist for acute stroke in Chile. In-hospital death is higher for acute ischemic stroke in men and higher for intracerebral hemorrhage in women. Future research is needed to better identify contributing factors.

Economics of Electrowinning Iron from Ore for Green Steel Production

The transition to green steel production is pivotal for reducing global carbon emissions. This study presents a comprehensive techno-economic analysis of various green steel production methods, including hydrogen reduction and three different electrolysis techniques: aqueous hydroxide electrolysis (AHE), molten salt electrolysis, and molten oxide electrolysis (MOE). By comparing process flow diagrams, capital and operational expenditures, specific energy consumption, and production footprint, this work provides a high-level assessment of the economic viability of these processes as they mature. The analysis reveals that MOE, despite its ongoing development, offers a promising route for iron production given its ability to process a wide range of ore qualities and the potential to sell electrolyte as a cement product. However, the best balance between deployment ready technology and economic benefit is AHE. Operational challenges are also discussed, such as electrolyte loss and slag handling. We suggest that the sale of by-products like oxygen may not significantly impact the economics due to market saturation. The findings underscore the importance of continued research and development in process optimization to realize the full potential of green steel technologies. All the calculations have been released as supplementary electronic material (MS Excel workbook). The format has been inspired by the techno-economic assessment template (TECHTEST) distributed by the US Dept. of Energy.Graphical

ANALISIS EFEKTIVITAS KINERJA KEUANGAN DALAM PENGELOLAAN ANGGARAN PEMERINTAH DAN BELANJA DAERAH PADA KOTA SURABAYA

This study aims to determine the effectiveness of the financial management performance of the Surabaya City Government for the 2015-2019 period. This study uses a quantitative descriptive method using an analysis of the effectiveness of regional financial performance, analysis of regional financial independence and analysis of compatibility (operational expenditure and capital expenditure). Using secondary data, the data processed is the Summary of Regional Revenue and Expenditure Budgets for the 2015-2019 Fiscal Year. The Regional Financial Independence of the Surabaya City Government has reached a very good level, which shows a pattern of delegative relations, which means that the intervention of the Central Government is no longer there because the regions are completely independent in implementing regional autonomy. The level of effectiveness of the Surabaya city government's financial management is fairly effective because from 2015 -2019 the effectiveness of the Surabaya city government's financial performance has always reached the target which is effective. However, the compatibility of the Surabaya government's financial performance has not been balanced. According to the description and calculations above, most of the funds owned by the Surabaya City Government are still prioritized for operational expenditure needs so that the capital expenditure ratio is relatively small.

Evaluating the agronomic and economic viability of biochar in sustainable crop production

This paper examines the economic viability of biochar application in crop production, focusing on varying application rates of 0, 4, 8, 12, 16, 20, 24, and 28 tons per hectare. Biochar, produced through biomass pyrolysis, has shown promise in improving crop yields and contributing to environmental sustainability. The biochar production financial metrics were analyzed, and it shows that the economic parameters such as Operational Expenditure (OPEX) amounting to $2339.40, feedstock cost of $2420.25, and transport cost of $293.71. The total biochar production cost was $232.87 per ton, with labour costs comprising 27.07 % of the overall production and application expenses. The analysis revealed that the maximum annual revenue from crop production (peas in the rabi season and maize in the kharif season) reached $525.88 per hectare at a biochar application rate of 12 tons/ha. Carbon sequestration revenue was estimated at $186.6 per ton of biochar. Economic indicators revealed that the benefit-cost ratio (BCR) was the highest at 1.476, with an 8 ton/ha biochar application rate. At the same time, the net present worth (NPW) and internal rate of return (IRR) also maximized at this rate, reaching $932.85 and 85.71 %, respectively. Conversely, higher biochar application rates of 24 and 28 tons/ha resulted in negative NPW and IRR values and BCR values below 1, indicating economic infeasibility at these levels. These findings highlight the economic viability and potential agronomic benefits of biochar application at optimal rates of 8 tons/ha for promoting sustainable crop production.