Search Results (70)

Industrial deployment of photocatalysis for recalcitrant wastewater treatment remains constrained by economic uncertainty and scale-up limitations. This study first reviews the current technological routes and application status of photocatalytic processes and then addresses the key obstacles through a quantitative techno-economic assessment (TEA) of a full-scale (10,000 m³/d) photocatalytic wastewater treatment plant. A process-level model integrating mass- and energy-balance calculations with equipment sizing was developed for a 280 kW UVA-LED reactor using Pt/TiO₂ as the benchmark catalyst. The framework quantifies capital (CAPEX) and operating (OPEX) expenditures and evaluates the overall economic performance of the photocatalytic treatment system. Sensitivity analysis reveals that the catalyst replacement interval and electricity tariffs are the principal economic bottlenecks, whereas improvements in catalyst performance alone provide limited cost leverage. Furthermore, the analysis indicates that supportive policy mechanisms such as carbon-credit incentives and electricity subsidies could substantially enhance economic feasibility. Overall, this work establishes a comprehensive integrated TEA framework for industrial-scale photocatalytic wastewater treatment, offering actionable design parameters and cost benchmarks to guide future commercialization. Full article

This study presents a comprehensive techno-economic assessment of offshore wind projects in the Colombian Caribbean, emphasizing the impact of site-specific parameters on development costs and performance. Wind resource conditions were evaluated in four coastal regions (La Guajira, Magdalena, Atlántico, and Bolívar) using hourly meteorological data from 2015 to 2024, adjusted to 100 m above ground level through logarithmic and power law wind profile models. The analysis included wind speed, bathymetry, distance to shore, distance to substation, foundation type, wind power density (WPD), and capacity factor (C_f). Based on these parameters, annual energy generation was estimated, and both capital expenditures (CAPEX) and operational expenditures (OPEX) were calculated, considering the technical and cost differences between fixed and floating foundations. Results show that La Guajira combines excellent wind conditions (WPD of 796 W/m² and C_f of 61.5%) with favorable construction feasibility (bathymetry of −32 m), resulting in the lowest CAPEX among the studied regions. In contrast, Magdalena and Atlántico, with bathymetries exceeding 200 m, require floating foundations that more than double the investment costs. Bolívar presents an intermediate profile, offering solid wind potential and fixed foundation feasibility at a moderate cost. The findings confirm that offshore wind project viability depends not only on wind resource quality but also on physical site constraints, which directly influence the cost structure and energy yield. This integrated approach supports more accurate project prioritization and contributes to strategic planning for the sustainable deployment of offshore wind energy in Colombia. Full article

Wavelength Division Multiplexing-based Passive Optical Networks (WDM-PONs) are among the most advanced optical networks without active elements, using a wide range of wavelengths to increase network reliability, scalability, and capacity. This ensures the provision of high quality, fast, and available services for end users. In this aim, traffic protection considerations have markedly enhanced their role. Traffic protection schemes can be divided into Point-To-MultiPoint (P2MP) and ring architectures. Traffic protection scenarios of access WDM-PONs in the P2MP architecture include Type B, dual-parented Type B, and Type C, while the ring architecture includes protected access and metropolitan-access WDM-PONs. Any potential traffic protection scheme can be represented by a corresponding reliability block diagram for the purpose of cost–benefit analysis. An important aspect of the WDM-PON design is presented by the Capital (CAPEXs) and Operational (OPEXs) Expenditures, which play a key role in network optimization. Managing them efficiently allows us to achieve an economically sustainable and efficient infrastructure of future passive optical networks involving traffic protection schemes. In this work, we focused on simulation model development for calculating the CAPEX and OPEX costs and the subsequent cost–benefit analysis of possible WDM-PON traffic protection schemes. Full article

This research determines the techno-economic feasibility of valorizing as biofertilizer the nitrogen (N) and the phosphorus (P) from a municipal wastewater effluent using the microalgae Scenedesmus sp., contributing to phosphorus recycling, resource optimization, and diminishing eutrophication by capturing 74% of N, 97% of P, and 41% of chemical oxygen demand in effluents. The inoculum was conditioned in 20 L photobioreactors by weekly harvesting and refilling at room temperature (25 °C day, 12 °C night) with a 12:12 photoperiod and 4 L/min atmospheric air bubbling. The improved operational conditions were obtained using a Box–Behnken experimental design, establishing that 70% wastewater concentration (vol./vol.), 4.5% nutrient addition, and 3 days’ harvesting time were the best conditions. The estimated biomass production was 176 tons/year, and this represents a maximum net present value of 1.5 MUSD for a 6.8 Ha plant, capturing 10% of municipal wastewater effluent, which serves 64000 inhabitants. The representative operational costs (OPEX) were 32% for utilities, 30% labor costs, and 25% for raw materials, and the required capital expenditures (CAPEX) were 11 MUSD and are related to photobioreactors (64%) and land (21%). The findings demonstrate the potential of microalgae-based systems as a feasible and profitable approach to wastewater valorization, while also highlighting the need for scale-up validation and integration with existing treatment infrastructures, where land requirements and photobioreactor installation will be relevant for financial feasibility. Full article

Seawater reverse osmosis (SWRO) desalination generates a concentrated brine byproduct rich in dissolved salts and minerals. This study presents an extensive economic and technical analysis of recovering all major ions from SWRO brine, which includes Na, Cl, Mg, Ca, SO₄, K, Br, B, Li, Rb, and Sr in comparison to conventional mining and chemical production of these commodities. Data from recent literature and case studies are compiled to quantify the composition of a typical SWRO brine and the potential yield of valuable products. A life-cycle cost framework is applied, incorporating capital expenditure (CAPEX), operational expenditure (OPEX), and total water cost (TWC) impacts. A representative simulation for a large 100,000 m³/day SWRO plant shows that integrated “brine mining” systems could recover on the order of 3.8 million tons of salts per year. At optimistic recovery efficiencies, the gross annual revenue from products (NaCl, Mg(OH)₂/MgO, CaCO₃, KCl, Br₂, Li₂CO₃, etc.) can reach a few hundred million USD. This revenue is comparable to or exceeds the added costs of recovery processes under favorable conditions, potentially offsetting desalination costs by USD 0.5/m³ or more. We compare these projections with the economics of obtaining the same materials through conventional mining and chemical processes worldwide. Major findings indicate that recovery of abundant low-value salts (especially NaCl) can supply bulk revenue to cover processing costs, while extraction of scarce high-value elements (Li, Rb, Sr, etc.) can provide significant additional profit if efficient separation is achieved. The energy requirements and unit costs for brine recovery are analyzed against those of terrestrial or conventional mining; in many cases, brine-derived production is competitive due to avoided raw material extraction and potential use of waste or renewable energy. CAPEX for adding mineral recovery to a desalination plant is significant but can be justified by revenue and by strategic benefits such as reduced brine disposal. Our analysis, drawing on global data and case studies (e.g., projects in Europe and the Middle East), suggests that metals and salts recovery from SWRO brine is technically feasible and, at sufficient scale, economically viable in many regions. We provide detailed comparisons of cost, yield, and market value for each target element, along with empirical models and formulas for profitability. The results offer a roadmap for integrating brine mining into desalination operations and highlight key factors such as commodity prices, scale economies, energy integration, and policy incentives that influence the competitiveness of brine recovery against traditional mining. Full article

Energy storage facilities serve as flexible resources that comprehensively support grid operations; they are also essential, especially when the thermal power plants that previously served as regulators run out. Electricity is becoming the dominant carrier through which the bulk of consumers’ energy needs are met. The efficiency of long-distance transmission and the ease of conversion to other forms of energy in Poland are attributed to the national grid. Thanks to the development of new technologies and distribution channels, energy is changing its supply network system. The purpose of this article is to discuss the economic viability of energy storage systems and their strategic role in the energy transition. The research methods used are data analysis, and the dependence on capital expenditures ($CAPEX$) and operating costs ($OPEX$) of energy storage in distribution channels. Energy storage facilities operated by grid companies account for 90% of the installed capacity, but there is a noticeable increase in the number of prosumer installations, with an energy storage of up to 50 KWh at microinstallations. Full article

This study investigates the financial and operational feasibility of deploying electric vehicle (EV) charging infrastructure within high-density residential buildings, utilizing empirical operational data combined with comprehensive financial modeling. A 14-day monitoring period conducted at a residential complex comprising 958 units revealed distinct charging behaviors, with demand peaking during weekday evenings between 19:00 and 22:00 and displaying more dispersed yet lower overall utilization during weekends. Energy efficiency emerged as a significant operational constraint, as standby power consumption contributed substantially to total energy losses. Specifically, while total energy consumption reached 248.342 kW, only 138.24 kW were directly delivered to users, underscoring the necessity for energy-efficient hardware and intelligent load management systems to minimize idle consumption. The financial analysis identified pricing as the most critical determinant of project viability. Under current cost structures, financial break-even was attainable only at a profit margin of 0.2286 USD (8 THB) per kWh, while lower margins resulted in persistent financial deficits. Sensitivity analysis further demonstrated the considerable vulnerability of the project’s financial performance to small fluctuations in profit share and utilization rate. A 10% reduction in either parameter entirely eliminated the project’s ability to reach payback, while variations in energy costs, capital expenditures (CAPEX), and operational expenditures (OPEX) exerted comparatively limited influence. These findings emphasize the importance of precise demand forecasting, adaptive pricing strategies, and proactive government intervention to mitigate financial risks associated with residential EV charging deployment. Policy measures such as capital subsidies, technical regulations, and transparent pricing frameworks are essential to incentivize private sector investment and support sustainable expansion of EV infrastructure in residential sectors. Full article

Decarbonizing air transport is a major challenge in the global energy transition since electrification is not yet feasible. Sustainable aviation fuel (SAF) is a promising solution because it can reduce CO₂ emissions without major infrastructure changes. This study proposes a decentralized model for producing SAF in Spain through the gasification of residual lignocellulosic biomass followed by a refinement process using Fischer–Tropsch (FT) synthesis. The model uses underexploited agricultural residues such as cereal straw, vine pruning, and olive pruning, converting them into syngas in medium-scale facilities situated near biomass sources. The syngas is then transported to a central upgrading unit to produce SAF compliant with ASTM D7566 standards. The following two configurations were evaluated: one with a single gasification plant and upgrading unit and another with three gasification plants supplying one central FT facility. Energy yields, capital and operational expenditures (CAPEX and OPEX), logistic costs, and the levelized cost of fuel (LCOF) were assessed. Under a conservative scenario using one-third of the available certain types of biomass from three regions of Spain, annual SAF production could reach 517.6 million liters, with unit costs ranging from 1.63 to 1.24 EUR/L and up to 47,060 tonnes of CO₂ emissions avoided per year. The findings support the model’s technical and economic viability and its alignment with circular economy principles and climate policy goals. This approach offers a scalable and replicable pathway for decarbonizing the aviation sector using local renewable resources. Full article

This article examines the evolution of the most extensively researched subjects in e-mobility during the previous two decades. The objective of this analysis is to identify the lessons that the State of Kuwait, which is falling behind other nations in terms of e-mobility, can learn from in its efforts to adopt electric vehicles (EVs). To strengthen the body of knowledge and determine the most effective and efficient route to an “EV-ready” nation, the authors compiled data on the latest developments in the EV industry. A bibliometric analysis was performed on 3962 articles using VOSviewer software, which identified six noteworthy clusters that warranted further discussion. Additionally, we examined the sequential progression of these clusters as follows: (1) the environmental ramifications of electric mobility; (2) advancements in EV technology, including range extension and soundless engines, as well as the capital expenditure (CAPEX) and operating expenditure (OPEX) of purchasing and operating EVs; (3) concerns regarding the effectiveness and durability of EV batteries; (4) the availability of EV charging stations and grid integration; (5) charging time; and, finally, (6) the origin and source of the energy used in the development of e-mobility. Delineating critical aspects in the development of e-mobility can help to equip policymakers and decision makers in Kuwait in formulating timely and economical choices pertaining to sustainable transportation. This study contributes by cross-walking six global bibliometric clusters to Kuwait’s ten EV adoption barriers and mapping each to actionable policy levers, linking evidence to deployment guidance for an emerging market grid. Unlike prior bibliometric overviews, our analysis is Kuwait-specific and heat-contextual, and it reports each cluster’s size and recency to show where the field is moving. Using Kuwait driving logs, we found that summer (avg 43.2 °C) reduced the effective full-charge range by 24% versus pre-winter (approximately 244 km vs. 321 km), underscoring the need for shaded PV-coupled hyper-hubs and active thermal management. Full article

Articulated Tugs and Barges (ATBs) are increasingly recognised for their effectiveness in transporting chemicals, petroleum, bulk goods, and containers, primarily due to their exceptional flexibility and fuel efficiency. Recent projections indicate that the ATB market is on track for significant growth, which is expected to lead to an increase in the annual growth rate from 2025 to 2032. This study aims to analyse the current advancements in ATB technology and provide insights into the ATB fleet and the systems that connect tugboats and barges. Furthermore, it highlights the advantages of this transportation system, especially regarding its role in enhancing energy efficiency within the maritime transport sector. Currently, there is limited information available in the public domain about ATBs compared to other commercial vessels. The analysis reveals that much of the required information for modern ATB design is not accessible outside specialised design companies. The study also focuses on conceptual design aspects, which include the main dimensions, articulated connections, propulsion systems, and machinery, concluding with an evaluation of economic viability. Special emphasis is placed on defining the main dimensions, which is a critical part of the complex design process. In this context, the ratios of length to beam (L/B), beam to draft (B/D), beam to depth (B/T), draft to depth (T/D), and power to the number of tugs cubed (Pw/N³) are established as design control parameters in the conceptual design phase. This aspect underscores the novelty of the present study. Additionally, the economic viability is analysed in terms of both CAPEX (capital expenditures) and OPEX (operational expenditures). While CAPEX does not significantly differ between the methods used in different types of commercial ships, OPEX should account for the unique characteristics of ATB vessels. Full article

This study provides a comprehensive techno-economic evaluation of the implementation of the 5G network, focusing on the southern region of Brazil. The research examines the capital expenditure (CAPEX) and operational expenditure (OPEX) associated with 5G deployment, assessing the economic viability of various deployment strategies. By analyzing international practices, such as sharing infrastructure, cutting networks, and using neutral networks, this study presents a detailed cost analysis and proposes models to optimize investment. A comparative evaluation of deployment costs between the southern region of Brazil and Belgium underscores the need to adapt European cost models to the Brazilian context. In addition, a case study on rural areas in southern Brazil identifies key challenges and opportunities, highlighting the unique aspects of the implementation of 5G in these regions. This study offers insights into optimizing investments in 5G networks, with the objective of supporting informed decision making for network expansion in diverse geographical and economic contexts. Full article

This research evaluates four hydrogen (H₂) production technologies via water electrolysis (WE): alkaline water electrolysis (AWE), proton exchange membrane electrolysis (PEME), anion exchange membrane electrolysis (AEME), and solid oxide electrolysis (SOE). Two scoring and ranking methods, the MACBETH method and the Pugh decision matrix, are utilized for this evaluation. The scoring process employs nine decision criteria: capital expenditure (CAPEX), operating expenditure (OPEX), operating efficiency (SOE), startup time (SuT), environmental impact (EI), technology readiness level (TRL), maintenance requirements (MRs), supply chain challenges (SCCs), and levelized cost of H₂ (LCOH). The MACBETH method involves pairwise technology comparisons for each decision criterion using seven qualitative judgment categories, which are converted into quantitative scores via M-MACBETH software (Version 3.2.0). The Pugh decision matrix benchmarks WE technologies using a baseline technology—SMR with CCS—and a three-point scoring scale (0 for the baseline, +1 for better, −1 for worse). Results from both methods indicate AWE as the leading H₂ production technology, which is followed by AEME, PEME, and SOE. AWE excels due to its lowest CAPEX and OPEX, highest TRL, and optimal operational efficiency (at ≈7 bars of pressure), which minimizes LCOH. AEME demonstrates balanced performance across the criteria. While PEME shows advantages in some areas, it requires improvements in others. SOE has the most areas needing enhancement. These insights can direct future R&D efforts toward the most promising H₂ production technologies to achieve the net-zero goal. Full article

Hydrogen offers a promising solution to reduce emissions in the energy sector with the growing need for decarbonisation. Despite its environmental benefits, the use of hydrogen presents significant challenges in storage and transport. Many studies have focused on the different types of hydrogen production and analysed the pros and cons of each technique for different applications. This study focuses on techno-economic analysis of onsite hydrogen production through ammonia decomposition by utilising the heat from exhaust gas generated by hydrogen-fuelled gas turbines. Aspen Plus simulation software and its economic evaluation system are used. The Siemens Energy SGT-400 gas turbine’s parameters are used as the baseline for the hydrogen gas turbine in this study, together with the economic parameters of the capital expenditure (CAPEX) and operating expenditure (OPEX) are considered. The levelised cost of hydrogen (LCOH) is found to be 5.64 USD/kg of hydrogen, which is 10.6% lower than that of the conventional method, where a furnace is used to increase the temperature of ammonia. A major contribution of the LCOH comes from the ammonia feed cost up to 99%. The price of ammonia is found to be the most sensitive parameter of the contribution to LCOH. The findings of this study show that the use of ammonia decomposition via heat recovery for onsite hydrogen production with ammonic recycling is economically viable and highlight the critical need to further reduce the prices of green ammonia and blue ammonia in the future. Full article

The growing scale of offshore wind farms and increasing transmission distances has driven the demand for optimized offshore substation (OSS) configurations. This study proposes a comprehensive techno-economic framework to minimize the total lifecycle cost (LCC) of an OSS by determining the optimal number of OSSs and transformers considering wind farm capacity and transmission distance. The methodology incorporates three cost models: capital expenditure (CAPEX), operational expenditure (OPEX), and expected energy not supplied (EENS). CAPEX considers transformer costs, topside structural mass effects, and nonlinear installation costs. OPEX accounts for substation maintenance and vessel operating expenses, and EENS is calculated using transformer failure probability models and redundancy configurations. The optimization is performed through scenario-based simulations and a net present value (NPV)-based comparative analysis to determine the cost-effective configurations. The quantitative analysis demonstrates that for small- to medium-scale wind farms (500–1000 MW), configurations using 1–2 substations and 3–4 transformers achieve minimal LCC regardless of the transmission distance. In contrast, large-scale wind farms (≥1500 MW) require additional substations to mitigate transmission losses and disruption risks, particularly over long distances. These results demonstrate that OSS design should holistically balance initial investment costs, operational reliability, and supply security, providing practical insights for cost-effective planning of next-generation offshore wind projects. Full article

To pursue the total decarbonization goal set at 2050, the introduction of hydrogen to replace the usage of fossil fuel in hard-to-abate industrial sectors is crucial. Hydrogen will replace natural gas in hard-to-abate sectors where natural gas is required to make heat necessary for the industrial process. Naturally, all this is worthwhile if hydrogen is produced following a green pathway, meaning that it is connected with renewable sources. In this manuscript, a techno-economic analysis related to a real case scenario is carried out. The real system addressed involves continuous high-temperature industrial furnace operation with a seasonally variable but stable thermal energy demand, representing typical conditions of hard-to-abate industrial processes. Solar photovoltaic panels combined with batteries are used to generate and store electricity that in turn is used to generate green hydrogen. Different scenarios are considered, including mixed natural gas/hydrogen, the seasonal variability of industrial needs, and the variability of solar production. The economic aspects considered include the usage of anion exchange membrane water electrolyzers (AEMWEs) to produce green hydrogen, the improvement in efficiency during operations (operational costs, OPEX), and the decrease in the AEMWE cost (Capital expenditures, CAPEX) that occur over time. The study shows that the hydrogen production cost could decrease from 12.6 EUR kg⁻¹ in 2024 to 9.7 EUR kg⁻¹ in 2030, with further reduction to 8.7 EUR kg⁻¹ achievable through seasonal blending strategies. CO₂ emissions are significantly reduced through partial displacement of natural gas with green hydrogen, highlighting the environmental potential of the system. Full article