Cost Of Electrical Energy Research Articles

Impacts of microwaves on the pectin extraction from apple pomace: Technological properties in structuring of hydrogels

The valorization of by-products eliminates the risks of economic barriers and reduces the overall amount of pollution and the carbon footprint of the products. In this context, conventional heating extraction (CE) and microwave-assisted extraction (MAE) were compared to extract pectin from apple pomace. The effects of temperature on MAE were evaluated based on the resulting properties obtained in subsequent pectin hydrogels. A pectin yield of 10.6 ± 0.3% was obtained by MAE with 5 min extraction, while CE showed a yield of 9.5 ± 0.3% after 2 h. The pectin extracted by both methods had a low methoxyl content, indicating a low degree of esterification. The galacturonic acid content was greater than 60% for most samples. Zeta potential analysis indicated the ability of the pectin to form stable gels. According to the X-ray diffractograms, increasing the extraction temperature led to a decrease in the crystallinity of the pectin structure. Rheological tests showed increased storage modulus as the temperature increased by MAE from 80 to 100 °C for the pectin-based hydrogel. The water holding capacity was greater than 50% for all hydrogels. Furthermore, an analysis of electrical consumption and energy costs highlighted the economic advantage of using microwave heating technology to extract pectin.

Sustainable Use of the Fungus Aspergillus sp. to Simultaneously Generate Electricity and Reduce Plastic through Microbial Fuel Cells

The improper disposal of plastic waste has become a significant problem, with only a small amount recycled and the rest ending up in landfills or being burned, leading to environmental pollution. In addition, the cost of electric energy has risen by over 100% in the last 20 years, making it unaffordable for remote areas to access this service due to high installation costs, leaving people living far from major cities without electricity. This study proposes an innovative solution to these issues using microbial fuel cell (MFC) technology to simultaneously reduce plastic waste and generate electric energy by utilizing the fungus Aspergillus sp. As a substrate for 45 days. The MFCs reached maximum values of 0.572 ± 0.024 V and 3.608 ± 0.249 mA of voltage and electric current on the thirty-first day, with the substrate operating at a pH of 6.57 ± 0.27 and an electrical conductivity of 257.12 ± 20.9 mS/cm. Furthermore, it was possible to reduce the chemical oxygen demand by 73.77% over the 45 days of MFC operation, while the recorded internal resistance was 27.417 ± 9.810 Ω, indicating a power density of 0.124 ± 0.006 mW/cm2. The initial and final transmittance spectra, obtained using FTIR (Fourier Transform Infrared), showed the characteristic peaks of polyethylene (plastic), with a noticeable reduction in the final spectrum, particularly in the vibration of the C-H compound. After 45 days of fungus operation, the plastic surface used as a sample exhibited perforations and cracks, resulting in a thickness reduction of 313.56 µm. This research represents an initial step in using fungi for plastic reduction and electric energy generation in an alternative and sustainable manner.

Development of a conceptual model for management of technological losses of electricity in distribution networks 150-0.38 kV

The work developed a conceptual model of the process of managing the technological costs of electrical energy in 150-0.38kV distribution networks. The relevance and necessity of developing a conceptual model of the process of managing the technological costs of electricity, which is carried out in relation to the system of distribution of electrical energy (or the electrical distribution system) as a whole, including distribution electrical networks of 150-0.38 kV, is analyzed. The paper proposes a conceptual decomposition, considers the description and formalization of the power distribution system management process based on the criterion of reducing the technological costs of electricity. The proposed conceptual model describes the process of managing the technological costs of electricity in the power distribution system, as a process of regular improvement (optimization) of the functioning of the power distribution system and allows further optimization and automation of the process of managing the technological costs of electricity in the power distribution system, in order to achieve higher levels of energy efficiency of its functioning. It is shown that this model can be used to solve the tasks of not only strategic and tactical management (in terms of years and months) when forming development plans and current operation of distribution systems, but also operational optimization of technological costs of electricity at the pace of the process. Provided that the appropriate software is developed (including the forecasting of power distribution system modes and external environmental influences), the system for managing the technological costs of electrical energy is represented by three control loops that correspond to the stages of its development. Processes and information links between them are shown for each control loop. Each process in the conceptual model of the management of technological costs of electric energy has its own formal representation through generalized functional dependencies, and the information links between the processes correspond to the arguments and values of these functions. The conceptual model describes the process of managing the technological costs of electrical energy in the power distribution system as a process of regular improvement (optimization) of its functioning through increasing its energy efficiency.

Photocatalyzed degradation of persistent organic pollutants via black TiO2 nanomaterials with four distinct morphologies: Energy and treatment cost estimation

For photocatalytic remediation of wastewater on an industrial scale, shaping the morphological properties of black TiO2 and reducing energy consumption and related treatment cost (t-cost) are essential. In this study, black TiO2 nanomaterials with four different morphologies—nanoparticles (TNPs), nanowires (TNWs), nanoflowers (TNFs), and nanonails (TNNs)—were produced, and their effectiveness in visible-driven photodegradation of model persistent phenolic compounds (PhCs) was evaluated. For every modification, the amount of energy consumed—primarily electrical energy (EE) and t-cost were estimated. The anatase structure was consistent throughout all the different morphological TiO2 samples, with a range of bandgaps of 2.4–2.93 eV, crystallite sizes of 13.86–18.49 nm, and significantly varying surface areas from 183.76 to 521.58 m2/g. TNFs were the most effective and versatile black TiO2 nanomaterials among the samples, as evidenced by their significantly higher removal efficiency of 77.99 % of total phenols (TPs). Furthermore, after 120 minutes of exposure to visible light, TNFs eliminated 100 % of the individual PhCs, including phenol, Ferrulic acid (FA), caffeic acid (CA), and gallic acid (GA). The TNFs required less than 170 kWh/m3 of EE with an estimated t-cost of less than 8 $/m3 for more than 80 % removal of all PhCs and reducing BOD5 and COD levels of the wastewater by 77.90 and 77.54 %, respectively. The estimated cost of the input materials was 39.52, while the EE cost was 5.045 with a total cost of 44.565 $ for producing 1 kg of the TNFs. Scavenging experiments revealed that the main reactive agents responsible for PhCs degradation were •OH radicals. This study provides evidence that adjusting the morphological characteristics of black TiO2 nanomaterials may be a useful tactic to lower the energy consumption and t-cost of photocatalytic remediation of wastewater contaminated with persistent organic pollutants.

Technical and economic assessment of hybrid PVT solar systems compared to independent solar thermal and photovoltaic collectors in high-temperature zones: A case study in Mexicali, Mexico

This study analyzes the technical and economic feasibility of hybrid photovoltaic/thermal (PVT) solar energy systems, comparing them with independent flat plate solar thermal collectors (FP) and photovoltaic (PV) modules. Using TRNSYS software, different configurations were simulated under the climatic conditions of Mexicali, Baja California, Mexico. The results indicate that, although independent FP and PV systems exhibit better energy performance in terms of energy production and solar fraction, PVT collectors offer higher specific global energy production (electrical + thermal). However, the economic feasibility of PVT systems is limited due to high investment and maintenance costs, coupled with the low cost of thermal and electrical energy in the study region. Independent FP and PV collectors also face similar economic challenges, with return on investment extending beyond the 20-year lifespan of the project. Additionally, the low thermal energy demand for domestic hot water in the studied region negatively impacts the efficient utilization of these systems. This analysis suggests that in contexts where available installation space is limited, PVT systems can be an efficient solution. However, in scenarios with sufficient space and high energy costs, energy generation with separate equipment remains more viable. Moreover, climatic conditions and DHW demand affect the efficiency of the systems. The discrepancy between solar energy generation and hourly DHW demand necessitates the implementation of TEST, which significantly increases costs and impacts the economic viability of the project.

DECREASING ELECTRICAL ENERGY COST AND INDIRECT CO2 EMISSIONS OF AN AIR CONDITIONING UNIT AFTER PREVENTIVE MAINTENANCE

During the summer season in subtropical countries and the dry season in tropical countries, air temperature is high. To adapt this condition, an air conditioning (AC) unit is used. The air conditioning use, however, increases the electrical energy consumption which contributes to the increase of indirect CO2 emissions. For many buildings, a monthly electrical energy cost from the use of AC system can contribute up to 40% of a monthly utility expenditure. It is then a great motivation to decrease electrical energy consumption of the AC unit. In this work, an adaptable preventive maintenance for an AC unit shows an acceptable level of electrical energy decrease. An experiment was performed for 2 AC types. The first one is a wall mounted unit with a cooling capacity of 9,300 BTUH. The second unit is a split duct unit with a cooling capacity of 48,000 BTUH. The cleaning of evaporator in the wall-mounted AC unit decreased the hourly electrical energy consumption by 4.1% from 810 to 777 Watt-hour. In addition, cleaning of condenser for the similar AC unit decreased the electrical energy consumption by 6.2% from 810 to 760 Watt-hour. Meanwhile, the evaporator cleaning for a 48,000 split duct AC decreased the hourly electrical energy consumption by 2.4% from 4.64 to 4.53 kWh and cleaning of condenser decreased the energy consumption by 5.4% from 4.64 to 4.39 kWh. If this electrical energy decrease could be scaled up to the global energy consumption from the air conditioning use, this should be a significant decrease of the global energy consumption and the correlated indirect CO2 emissions from the air conditioning sector.

Optimization of a hybrid system (PV-fuel cell) of energy production for an isolated site

In recent years, there has been a significant shift in the design and implementation of autonomous micro-grid systems, moving away from the traditional reliance on fossil fuels. Instead, these systems are now integrating existing renewable energy sources available in specific geographic locations to promote sustainability and environmental responsibility in the energy sector. One particularly promising approach for energy storage and transmission is through the utilization of hydrogen and solar energy, especially in remote regions where hybrid techniques can effectively meet the required energy demands. Our research focuses on electrifying an agricultural site located in the SBAA region, specifically in the city of ADRAR, southwest Algeria. We propose the implementation of an independent small electric network that combines various renewable energy sources, including photovoltaic (PV) systems and fuel cells. To ensure cost-effectiveness and optimize the system's performance, we aim to carefully control and size the system's components through a meticulous selection process. The primary objective of this study is to evaluate the technical and economic feasibility of implementing renewable energy systems in the targeted region. Our goals are to reduce the total net cost, minimize energy expenses and unfulfilled load, while simultaneously mitigating CO2 emissions. To achieve these objectives, we employ the HOMER Pro simulation program, which enables us to conduct a comprehensive analysis of the proposed system's performance and economic viability. The proposed system incorporates a hybrid configuration of PV panels and fuel cells, leveraging the complementary nature of these two renewable energy sources. PV panels harness the abundant solar energy during daytime hours, while fuel cells provide a reliable and consistent energy source during periods of low solar irradiance or at night. By integrating these two technologies, we aim to establish a self-sufficient and sustainable energy system capable of meeting the energy demands of the remote agricultural site. Overall, the proposed renewable energy system demonstrates positive results in electrifying remote areas while maintaining a conservative cost of electrical energy. By implementing this system, we not only contribute to the establishment of sustainable regions but also promote environmental stewardship by reducing carbon emissions and dependence on fossil fuels.

ОБОСНОВАНИЕ ПРИМЕНЕНИЯ ДИФФЕРЕНЦИРОВАННОГО СОЦИАЛЬНОГО ТАРИФА НА ЭЛЕКТРИЧЕСКУЮ ЭНЕРГИЮ ПРИ РЕАЛИЗАЦИИ ПРОЕКТА ЭЛЕКТРОСНАБЖЕНИЯ ОТ АВТОНОМНОЙ ГИБРИДНОЙ ЭНЕРГЕТИЧЕСКОЙ УСТАНОВКИ

The issue of uninterrupted power supply to remote settlements is relevant in many countries of the world, but especially in Russia. Modern autonomous hybrid power plants (AHPP), namely solar power plants (SPP), wind power plants (WPP) and other power plants using renewable energy sources (RES), combined with diesel electric power plants (DES), provide not only an increase in the amount of electricity generated, but, most importantly, they ensure uninterrupted power supply to consumers through a combination of renewable energy sources and covering the missing energy from diesel power plants. In the conditions of the northern areas of the Krasnoyarsk Region, this is especially important. ASPPs make it possible to reduce the cost of electrical energy by saving fuel consumption and budgetary subsidies for its supply to remote areas of the region. The purpose of the study was to substantiate the areas of application of autonomous hybrid power plants for the regions of the Far North with the possibility of establishing a differentiated social tariff for household consumers. To achieve the goal, load coverage graphs were constructed for Vanavara settlement; the parameters of the ASPP were studied for the conditions of Vanavara settlement; simulation of the operating modes of the ASPP was carried out; calculation of the main technical and economic indicators of the use of ASPP for power supply to Vanavara settlement was carried out; recommendations were given on rational areas of application of ASPPs with the possibility of applying special tariffs for the electricity they produce. The authors of the paper carried out a technical and economic assessment of ASUE in the Vanavara settlement with a capacity of 10 MW, including a solar power plant with a capacity of 2,5 MW. It was established that the cost of electrical energy in the first option when powered by diesel power plants is 36,75 rubles/kW.h. In the second option, the cost depends on the time of year and is 32,7 rubles/kW.h in winter, 11.6 in spring, 6.05 in summer, and 12,2 rubles/kW.h in autumn, which makes it possible to establish a differential social tariff for household consumers based on a lower cost in the summer in the amount of 7–9 rubles/kW.h.

Technical and economic study of renewable-energy-powered system for a newly constructed city in China

The power and transportation sectors are major carbon emission sources of cities in China, meanwhile, urbanization and industrialization remain the most important impetus for the Chinese economy. Thus, urban-level carbon mitigation is critical for China to realize a low carbon development strategy. This study designs two renewable-energy power-generation dominated power systems for a totally newly built Chinese city, Xiongan, considering emerging technologies, such as vehicle-to-grid as an energy storage facility and geothermal as a local renewable energy resource. The new energy systems are assessed from both economic and carbon emission aspects based on short &long terms power load forecasts. The simulation results shows that the optimal short-term system is a photovoltaic (PV)/geothermal generator/grid purchase/100 Li battery/converter. For the short term, the system's net present cost (NPC) is approximately $8.26B, and the average cost of valuable electrical energy (COE) produced by the system is approximately $0.0942/kWh. The optimal long-term system is a PV/geothermal generator /V2G/ converter, the NPC of the optimal system is approximately $47.7B, and the COE of the system is approximately $0.078/kWh. Energy bill and carbon emissions can both be cut sharply for the city if it adopts these new types of renewable energy dominated systems.

Optimization and monitoring of solar power plant as a hybrid energy for tea leaf dryer based on SCADA system

Previous research has discussed tea drying machines with energy sources from PLN. Tea drying machines with refrigerant systems require large electrical energy costs. The electrical energy produced by a tea drying machine is proportional to its performance and cost. This research designed a 400 WP solar cell (PLTS) as a power supply for drying tea leaves. PLTS was combined with a PLN electricity source. Hybrid energy from PLTS and PLN was designed to maximize the use of electrical energy used by drying tea leaves. PLC and SCADA were used to monitor input current, output voltage, and output power. PLC and SCADA can optimize load requirements. When the solar radiation received by the solar panels was not optimal, PLN was able to back up load requirements. The average voltage produced by hybrid energy was 232.4 V. Hybrid energy was able to save power usage of 108.92 W or 12.8% of the load power requirements

Analysis of the alternative air ductwork by Numerical airflow behavior combined with the New Economic index and standard

This research studies the numerical modelling using computational fluid dynamics with a k-Epsilon turbulence model to analyze airflow behaviors inside the alternative compared with conventional air ductwork combined with a comprehensive analysis of the economic parameter created by the author called Reveal Comparative Advantage Cost index. All alternative air ductwork has lower pressure drop and a higher ability to maintain the temperature inside, showing that alternative air duct systems have a significant advantage over conventional air ductwork. The fabric ductwork has a lower pressure drop than galvanized steel perforated ductwork, which is 69.15 %. The pre-insulated ductwork can keep the best temperature inside, with a different temperature value between the air inlet and air outlet of 0.06°C. The Reveal Comparative Advantage Cost of construction costs of the galvanized steel ductwork and the galvanized steel perforated ductwork are 1.02 and 1.06, which means the conventional air ductwork is initially cost-effective in terms of investment and operating costs. However, alternative air ductwork is the better option for long-term use. They have cost-effective electrical energy and maintenance costs with a high Reveal Comparative Advantage Cost index. Significantly, the pre-insulated ductwork has the Reveal Comparative Advantage Cost index of maintenance, electrical energy, and construction costs of 1.38, 1.09, and 0.95, respectively. The results of the airflow behaviors study combined with the Reveal Comparative Advantage Cost index study show that the galvanized steel perforated ductwork is not a selectivity that qualifies either for airflow behaviors or is unsuitable for investment. Pre-insulated ductwork is the appropriate option due to the high airflow behaviors and cost, which makes it suitable for investment. However, the Thailand Authority should develop alternative air ductwork Thai standards for engineering design and safety building.

Multi-objective modeling and optimization of the SOFC stacks based on the unit cost of electric energy produced, efficiency and output power using fractional-order Kho-Kho optimization algorithm

ABSTRACT Energy generation systems based on FC (fuel cell) are viewed as a viable substitute for those that simply rely on thermodynamic cycles in the power production field. In this paper, a 10-stack SOFC systems performance and optimization of that utilizing a newly improved optimizer known as the Fractional-order Kho-Kho optimization method will be presented in this paper. The multi-objective optimization approach is applied in the optimization phase to achieve the desired performance goals for the SOFC system. With the help of this technique, the desired system can be optimized in accordance with two objective functions: first, the electric power of the system can be maximized, while the equalized price of the electricity produced is minimized. Then, the electrical efficiency of the system can be maximized, while the equalized price of the electricity produced is minimized. The results show that, by reducing the coefficient and increasing efficiency, optimal solutions were achieved with higher electricity prices. It is observed that an increase in energy prices led to a 9% increase in productivity, whereas a 15% increase resulted in only a 2% increase. The findings demonstrate that multi-objective optimization may be used as a sophisticated analytical tool as well as a guiding element for decision-makers utilizing such a system.

Experimental and simulation investigation of a Savonius vertical axis wind turbine for residential applications: a case study in Indonesia

The aim of this study was to investigate several geometric designs to improve the performance of a Savonius vertical axis wind turbine (SVAWT) at low wind speeds. The SVAWT models were numerically tested using ANSYS prediction software to determine the best performance. Furthermore, a SVAWT prototype was experimentally evaluated in subsonic wind tunnels at wind speeds of 1–5 m/s to determine the electrical power produced. The experimental results were used as input parameters for HOMER tools to optimise renewable energy systems and establish the prototype’s techno-economic environmental viability for satisfying the residential demand load. The simulation results showed that the maximum power coefficient obtained was 0.25 for a SVAWT model with a twist angle of 45° at a wind speed of 5 m/s. The experimental results showed that the modified SVAWT produced 494.9 W of electrical power at a wind speed of 5 m/s. The results confirmed that the cost of electrical energy following an initial investment in the optimised renewable energy system configuration (a grid-connected 1-kW SVAWT with a – kW electrical converter and two battery strings) was 0.0963/kWh and 4,425. This setup achieves a 65.8% renewable fraction, cutting CO2 emissions by over 53.71%, fit for residential use.

Empowering Active Users: A Case Study with Economic Analysis of the Electric Energy Cost Calculation Post-Net-Metering Abolition in Slovenia

This paper addresses the issue of the abolition of annual net metering in Slovenia and compares the electric energy costs for the studied active user after the abolition. The article also provides an exploration of the role played by an aggregator, which serves as a central entity that enables individuals to participate in the electric energy market. An analysis of the case study of an active user was made, where an analysis was made of the measurements of household consumption and photovoltaic plant production for the year 2022. This article presents an economic analysis with and without net metering and an analysis of the aggregator involvement strategies. In addition, a battery energy storage system was also considered in the analysis. An important part of the article is the identification of the flexibility potential for shiftable loads, which enable an aggregator to acquire insight into the energy consumption profile and energy production profile of active users. The following indicators were used to compare the strategies: annual electric energy cost and the indicators including self-sufficiency, self-consumption, and grid dependency. The findings indicate that, even in the absence of annual net metering, the active user can lower their costs for electric energy with the help of an aggregator.

A Model for Electrifying Fire Ambulance Service Stations Considering Practical Service Data and Charging Strategies

Due to concerns with air pollution and climate change, governments and transport operators around the world have engaged in transforming their fossil-fueled vehicles into electric vehicles (EVs). It is essential to build a model for the electrifying process to minimize the operation costs. This paper presents a systematic analytical approach for the electrification of a fire ambulance service station. This approach begins with the selection of suitable EVs to replace the current service vehicles. Subsequently, an in-depth analysis is conducted to determine the practical utilization of EVs at the station. The model proposes two charging strategies: immediate charging upon an EVs’ return and smart charging. Based on the chosen EVs and charging strategies, a comprehensive assessment of the load profiles for the planned EV charging station is performed. In accordance with the load profiles, a mathematical model to minimize the infrastructure and operation costs of the charging station is proposed. Various pricing schemes are compared to identify the most efficient pricing scheme for the charging station, and economic analyses of the EVs and traditional ambulance vehicles are proposed in this paper. The test results indicate that the progressive pricing scheme is well suited for immediate charging strategies, whereas smart charging should opt for the time-of-use pricing scheme. Selecting the appropriate pricing scheme has the potential to significantly reduce electric energy costs.

Maximizing Solar Panel Performance: A Comparative Study of Aluminum and Copper Panel Integration in Off-Grid Systems

Abstract: This study explores the implementation of off-grid solar energy systems with strategically mounted aluminum panels behind solar panels, aiming to devise an efficient, economical, and environmentally friendly design. The research builds upon existing literature in the field, focusing on optimizing solar panel performance. Through a comprehensive analysis involving voltage, current, temperature, and solar radiation, the study achieved a notable 1-2% increase in solar panel efficiency. Notably, this enhancement is realized without the need for additional space, making the proposed design a practical and space-efficient solution. The findings underscore the potential of this approach as a permanent, cost-effective, and environmentally conscious solution for PV solar panel installations. With the escalating costs of conventional electrical energy, the study advocates for the adoption of this method, aligning with the global push towards sustainable and eco-friendly energy alternatives. The insights gleaned from this research contribute valuable knowledge to the ongoing discourse on advancing renewable energy technologies, emphasizing the significance of efficient and sustainable solutions in the transition towards a cleaner energy future.

Audit Dan Peluang Penghematan Energi Listrik CV Tirta Windu Agung 3 Probolinggo

The use of electrical energy in the building and industrial sectors is very important, especially the use and allocation of funds spent is quite large. So it is necessary to use energy as efficiently as possible. So there is a need for an energy audit to determine the level of electrical energy consumption used, where the results will be compared with predetermined standards. This research was carried out at CV Tirta Windu Agung 3 using a PM5100 and lux meter. From initial audit calculations, the IKE value was found to be 13.42 kWh/m2/year. This IKE value is the total of the buildings and ponds. The IKE value still includes very efficient criteria. Based on the results of detailed audit calculations, the value obtained before improvement was 2.23 kWh/m2/year. The IKE value still includes the criteria for being very efficient or meeting standards. After improvements it became 1.65 kWh/m2/year. Energy saving opportunities are available in indoor and outdoor lighting systems by replacing CFL (compact fluorescent lamp) lamps with Philips LED lamps. Based on calculations, the savings in electrical energy costs are IDR 41,736/day, resulting in savings of IDR 15,233,640/year. Based on the Isc/IL calculation above, it can be seen that the Isc/IL value is 165.4. According to the IEEE 519-2014 standard, the ISC IL value in the range >1000 has a permissible THDi value limit of 15%. The nominal voltage used is 0.4 kV, so the permitted THDv is 8%. Based on table 3.9 THDv and THDi under standard conditions.

Critical Review of the Metallurgical Operation of the Greek Nickel Industry and Perspectives, based on the recent Industrial Experience on Smelting Reduction Process

The mining and industrial production of Greek ferronickel industry LARCO have ceased since 30.07.2022. The last LME nickel price crisis, exclusion from bank loaning, extremely high cost of electrical energy, management issues, resulted inter alia, in a prohibitive operational cost. Nevertheless, LARCO faces the challenge of restructuring and reoperation in the future, given that privatization is in progress, including the acquisition of the company’s assets to a joint venture enterprise.
 Within this framework, the current paper aims to contribute to the discussion for developing a new management strategy for the optimization of pyrometallurgical process, focusing on the critical step of smelting reduction. Based on industrial experience concerning open bath submerged arc electric furnaces, factors which critically affect the safety and cost-effectiveness of smelting reduction are detected and presented by means of case studies, being mainly classified as following: i) Optimal raw materials’ feed management, including laterite ores (domestic or not), solid fuels and electrode paste. Moreover, taking for granted the need for Ni-rich ‘foreign’ ores to increase the recovery and reduce the cost of the process, the extent of dependence on Fe-rich domestic ores is investigated, in order a safe and stable operation to be ensured. ii) Focus on preventive maintenance management. Substantial increase of the facilities’ operational index and cost saving is obtained, as proved by operational case studies. iii) Modern human resources management strategy. Their economical footprint is further discussed.

Feasibility of Residential Wind Energy Generation in Puerto Rico

In Puerto Rico the rising cost of electrical energy from fossil fuels has created the necessity to use alternative energy sources for electricity generation. Wind energy, an accessible and clean source of energy, can help Puerto Rico achieve energy independence. Due to high population density, urban spread, lack of land use planning and the ever-growing concerns for the safety of flora and fauna, large-scale commercial wind generation has been met with increasing public opposition. Residential wind energy is most commonly used by homes and private land owners, making it less controversial. In this study we analyze recently obtained wind speed data from CariCOOS to help select a small residential wind turbine. An economical analysis of a residential wind turbine project is presented using the estimated energy produced.

Justification of the effective distribution of energy emitted by a film electric heater on stacked lumber

The research was carried out at the expense of the grant of the Russian Science Foundation No. 23-76-01090, https://rscf.ru/project/23-76-01090/. The article considers the issue of placing boards in a drying plant using infrared film electric heaters. Two options for placing one cubic meter of boards with a thickness of 25 mm and 50 mm are proposed for consideration. The boards are placed between shields with film electric heaters and are separated from each other by transverse gaskets, it is obvious that more gaskets are needed to accommodate boards with a thickness of 25, which means that the distance between the boards will be greater. Hence the hypothesis: an increase in the distance between the shields will lead to an increase in drying time and electrical energy costs. For a theoretical solution, the following is proposed – to present the piled stack in the form of a prism and, considering the known dimensional parameters of the skipped shield, according to a well-known formula, it is possible to obtain a dependence describing changes in the irradiation coefficient on the distance in the radiator-receiver system. The considered irradiance coefficient shows how much of the total radiation from the area of the “receiver” falls on the surface of the “receiver”. As a result, an exponential dependence is obtained, according to which it can be determined that the irradiation coefficient for the placement of boards with a thickness of 25 mm is 8% less than for boards with a thickness of 50 mm, which ultimately will affect the duration of the drying process and the cost of electrical energy. Options are proposed to increase the drying efficiency by increasing the irradiation coefficient by reducing the distance between the panels with film electric heaters. In conclusion, in view of the result described in this article, the main directions for further research on improving the “radiator-receiver” system in relation to drying plants based on film electric heaters are given.