Kind Of Renewable Energy Source Research Articles

Selection of a reliable energy source suppling domestic hot water (DHW) system in the kindergarten – a case study

Renewable energy sources (RESs) are used more and more frequently as energy sources for heating and domestic hot water (DHW). However, there are many factors influencing the energy efficiency, thus also ecological benefits. Before making a decision what kind of RES is useful and reliable, a comprehensive analysis should be conducted taking into account technical, financial and ecological factors. This paper discusses different variants of energy sources that could be applied in a kindergarten building for preparing hot water, in place of existing solution (district heating system, DHS). An air heat pump (AHP) with photovoltaic panels (PV) were considered the most reliable energy sources in the analysed building, in terms of economic and environmental considerations. The simple payback time (SPBT) for this investment was estimated as 14.55 years. This solution causes the lowest CO2 emissions. Another system with solar collectors supplying hot water preparation in the heat center can be also recommended. The simple payback time in this case was slightly higher (14.94 years) and what is more, a decrease in CO2 emissions was observed compared to the actual conditions.

Implementation of Digital Twin for Increasing Efficiency of Renewable Energy Sources

This paper presents an analysis of the instability of the electricity generation of renewable energy sources (RESs), specifically Digital Twins of RESs. The first part deals with the analysis of RES electricity generation around the world and Ukraine. The following chapter describes features of functioning power grids in modern conditions in Ukraine and ways to ensure the balance reliability in the power system for conditions of high-grade RES integration. The rapid increase in electricity generation RESs causes control problems of distributed power supply in the power grid. A mathematical model of the parameter controls in normal mode electric power systems for conditions with high integration of RESs is proposed in the second part. The study investigates components of the optimality criterion at the control of normal mode parameters of the electric power system with RESs. In general, digital transformation helps decarbonize the energy supply, decrease dependency on fossil fuels, and integrate renewables into power systems. A model Digital Twin (DT) of a photovoltaic system, or an exact 3D visualization, analyzing the accumulator system depending on load and generation, are presented. The problems of Digital Twin are very widely discussed, but many papers and studies are general without any practical implementations. The main part of this paper focuses on research and deals with daily electricity generation from different kinds of RESs, namely mini-hydropower stations, photovoltaic power stations, and wind power stations. Measured data of electricity generation from photovoltaic power plants, wind power plants, and mini-hydropower plants and obtained meteorological factors were used for the calculation of Spearman’s, Kendall’s, and Pearson’s correlation rank coefficients. The main contribution of this research is to determine the main metrological factors for each kind of studied RES. In the future, it will help to decide the task of forecasting power generation more presciently. Additionally, the presented model of DT RESs allows the installation and operation of grids with higher efficiency, because it can help to predict all influences, from shading up to the optimization of the battery storage system.

A Fault Detection Method in Photovoltaic Systems Based on the Deficiency Identification Algorithm

Solar energy is a kind of renewable energy source, power production, and stored in a battery for energy management systems. Fault identification is the Direct Current (DC) side of a PV (photovoltaic) system, which is difficult to avoid energy loss in such open-circuit and short-circuit-based renewable energy storage systems. Maximum power point tracking is the existing photovoltaic fault identification technique and it mainly improves the maximum Value of Photovoltaic Power at the Output Side. The Proposed Deficiency Identification Algorithm is used to improve the detection rate of fault occurrence in the PV cell. The Deficiency Identification Algorithm is implemented to detect the fault in the PV arrays. The open circuit fault and short circuit faults are the two major faults in the PV arrays. Solar irradiance level and the temperature are the two output characteristics which decide the output of the panel and also force to employ a battery unit that pedals the PV output and is particularly significant for improving energy conversion, voltage losses and improve efficiency.

Solar Energy Development Prospects in the Republic of Dagestan

Solar energy development prospects in the Republic of Dagestan are analyzed. The expected amount of electricity generated by solar power plants is estimated. The data obtained have shown that this region has a sufficient potential for the development of solar energy, which makes it possible to compensate for the shortage of electricity generation in the Dagestan electric power system equal to 3.1 billion kWh per annum. Electric power generation versions implying the use of photovoltaic converters (PVC), a solar tower with Rankine cycle planar heliostats (STPP), and a Stirling cycle parabolic dish heliostat (PDPP) are considered. In terms of technical and economic indicators, the PDPP is more preferable, and good prospects of the system are beyond doubt. However, more matured PVC and STPP technologies are presently put is use on a mass scale in the big energy sector. In view of a significant scatter in the technical and economic indicators around the world, for the PVC, STPP and PDPP technologies to be compared in a correct way, they should be implemented according to the standards and prices of one country. The kinds of renewable energy sources that are probabilistic in nature should be considered in the big electric power industry as backup-and-replacement sources; i.e., their function is to save hydrocarbon and, to a certain extent, nuclear fuel. The introduction of these technologies in the Republic of Dagestan will make it possible to save a significant amount of hydrocarbon fuel in the United Power System of South (for example, 706329114 m3 of gas, which necessary to generate the amount of electricity equal to the above-mentioned shortage, by thermal power plants operating with efficiency equal to 40%). This is important, because the absolute calm in 2021 in the European wind energy caused a jump in the spot price of gas up to $1969 for thousand cubic meters, whereas the price of Gazprom's exports to the far abroad was $313.4 for thousand cubic meters. When exporting gas at these prices, the state will receive $1390762026 or $221363544, respectively, and $191028200 when exporting electricity directly in the amount of the above-mentioned shortage. The obtained study results can be used in the development of regional and local programs of stimulating investments in the renewable energy. Gas exports are currently more profitable than the direct exports of electricity, and the proceeds gained from the gas exports should preferably be invested in the further development of renewable energy.

Effect of Blade Leading and Trailing Edge Configurations on the Performance of a Micro Tubular Propeller Turbine Using Response Surface Methodology

With the recent rise in importance of environmental issues, research on micro hydropower, a kind of renewable energy source, is being actively conducted. In this study, a micro tubular propeller turbine was selected for study of micro hydropower in pipes. Numerical analysis was conducted to evaluate the performance. Response surface methodology using design of experiments was performed to efficiently investigate the effect of the blade leading and trailing edge elliptic aspect ratios on the performance. The trailing edge configuration was found to be more related to the performance, because of the drastic pressure variation due to the stagnation point formed, regardless of the leading edge configuration. To improve the performance, a NACA airfoil was introduced. The results show that the flow became more stable than the reference model, and the efficiency was increased by 2.44%.

Location selection for waste-to-energy plants by using fuzzy linear programming

Effective energy management has become more prominent with the population growth and increasing industrialization. In order to provide an effective planning, it is important to use all kinds of renewable energy sources efficiently. The main renewable energy sources are solar, geothermal, biomass, hydropower and wind. Agricultural, forest, animal and municipal solid wastes are considered as potential resources for biomass. However, the uncertainty in the obtained amount of biomass complicates the related facility investment decisions. Fuzzy linear programming is quite useful to handle impreciseness in resource availability constraints. Therefore, in this paper, the most suitable locations for waste-to-energy power plants in Central Anatolia Region of Turkey are investigated by using a fuzzy linear programming model. It is concluded that Ankara, Konya, Kayseri, Eskisehir, Sivas and Aksaray are the most suitable cities for the investment.

PWM effect on MPPT for hybrid PV solar and wind turbine generating systems at various loading conditions

Hybrid systems employing different kinds of renewable energy sources, like wind and solar energy conversion systems, are used to reduce generation costs and the pollution of traditional fossil fuel-based electrical generation methods. The current paper presents the design of an off-grid hybrid connection of an 852 W photovoltaic (PV) panel with a 1 kW small-scale wind turbine. This work is based on a study of the effect of the changes in the pulse width modulation (PWM) of a DC/DC converter that was connected to each renewable energy source at various loads. The pulse width can be varied by changing its duty cycle value (D). In this paper, the D value is changed manually for each renewable energy source and automatically using an incremental conductance (IC) and Perturb and Observe (P&O) maximum power point tracking (MPPT) algorithms. The IC algorithm is used for the PV system whereas the P&O algorithm with a smaller step size is used for the PMSG wind turbine. The hybrid system is exposed to different environmental conditions to test the validity of the MPPT algorithm for both renewable energy sources. The results of manual and automatic changes of D values are compared for different loads. The AC output voltage is regulated to obtain a constant RMS voltage at different loads. The hybrid system is tested and simulated using MATLAB SIMULINK R2017a software.

Comprehensive review on various parameters that influence the performance of parabolic trough collector.

Among the different kinds of renewable energy sources, solar energy plays a major role because it is safe and inexpensive at all times. Several techniques are developed for steam and electricity generation by solar energy, in which the parabolic trough collector is an advantageous method for generating steam and electricity. Different types of collectors for various temperatures, in which PTCs are used to produce medium temperature ranges using the readily available solar energy, were developed, produced, and tests. Many theoretical and experimental studies have been carried out to improvise parabolic trough collectors' optical and thermal characteristics. The modifications are reviewed in this paper to enhance the design modification, optical and thermal properties utilized in the collector. This analysis paper also elucidates the use of PTC desalination, various integrated parabolic trough collector methods for power generation, and the economic aspects of parabolic trough collector.

A Stochastic Voltage Stability Constrained EMS for Isolated Microgrids in the Presence of PEVs Using a Coordinated UC-OPF Framework

Microgrids are increasingly affected by volatile wind energy due to the high penetration of this kind of renewable energy sources. This study investigates the impact of wind energy uncertainty on voltage stability and energy management system (EMS) of isolated microgrids in the presence of plug-in electric vehicles (PEVs). A stochastic voltage stability constrained microgrid energy management system (SVSC-MEMS) architecture based on a coordinated unit commitment-optimal power flow (UC-OPF) methodology, which simultaneously considers the UC and OPF constraints, is proposed. The proposed model guarantees the system security from the voltage stability standpoint, considering a specific loading margin. Besides, the role of PEVs in the microgrid EMS is examined. In order to validate the performance of the introduced SVSC-MEMS, a CIGRE benchmark test system is used. The numerical results, obtained from the implementation of the proposed model in the general algebraic modeling system (GAMS) environment, demonstrate the importance of voltage stability and wind power uncertainty on the microgrid EMS, and furthermore, the key role of PEVs in the emerging microgrids.

Multi-objective dynamic economic emission dispatch based on electric vehicles and wind power integrated system using differential evolution algorithm

Electric vehicles (EVs) are currently the most popular green transportation. Wind power has received widespread attention as a kind of renewable energy source. Their rapid development has brought new challenges for the power grid. However, the technology of vehicle to grid (V2G) can realize the peak shaving of the power grid, which is considered to be an effective method to promote the integration of EVs and wind power. Therefore, in this paper, a novel integrated framework of EVs and wind farms (WEV) is proposed to use the EVs charging and discharging to smooth the wind power penalty cost that caused by overestimated and underestimated of available wind power. While a new multi-objective dynamic economic emission dispatching model based on the WEV system (WE_DEED) is developed to consider both emission and total cost objectives. In order to solve the complex constrained WE_DEED problem, we propose a multi-objective differential evolution algorithm with the self-adaptive parameter operator and local search operator based on non-dominant sorting (SaMODE_LS). Moreover, an effective constraint handling method is applied to deal with the constraints in WE_DEED problems. Different test systems based on 10-unit are given to demonstrate the reasonability and efficiency of the proposed model and method.

Is emission trading scheme an opportunity for renewable energy in China? A perspective of ETS revenue redistributions

Emission Trading Scheme (ETS) and renewable energy generation are emission reduction methods in most countries in the world. However, few studies have focused on the impact of ETS on renewable energy. The question is, can carbon trading promote renewable energy generation? This paper first analyzes different distribution strategies of ETS revenue by applying dynamic recursive computable general equilibrium model with multi-sectors. Practical scenarios and better options of distribution of ETS revenue by a comprehensive evaluation based on entropy weight method are proposed. The results show that ETS with no subsidy to renewable will reduce the demand for energy, increase the cost of renewable energy sources and decrease the generation. ETS will be the spring of renewable energy generation when most of the revenue is used for all kinds of renewable energy sources, instead of some of them. The growth of renewable energy generation is also substantial. It is necessary that a small portion of ETS revenue should be used to subsidize residents to reduce the gap between the rich and the poor. If this income is used for government investment and consumption, it will also help to mitigate economic losses, which is caused by the direction of investment by the Chinese government.

Torrefaction of oat straw to use as solid biofuel, an additive to organic fertilizers for agriculture purposes and activated carbon – TGA analysis, kinetics

In this paper authors present research results which are the optimum parameters of the torrefaction process using straw from oats and maize. The most important parameters for the torrefaction process are temperature and residence time. Both parameters are essential to designing and construction of industrial biomass torrefaction installations. Energy crops and waste coming from agricultural production have the most promising perspective from all kind of renewable energy sources in Poland. Currently, intensive studies on the process of biomass torrefaction are being carried out. In this experimental investigation, authors examined the torrefaction process of two types of agriculture biomass, such as: oats, maize. The main overarching objective of the experimental studies described below is the development of various biochar as an additive to agricultural fertilizers resulting from the conversion of biomass from agriculture residues – straw from oats and maize. The last of enumerated biomasses is treated through different conversion processes such as: drying, torrefaction to homogenize their physical and chemical properties. Among many of its areas, it is extremely important to optimize the production of biomass energy plants and its refinement (in the torrefaction process), which will improve the balance and profitability of energy production from RES, and reduce the logistics and storage costs of this fuel and improve the efficiency of biomass combustion process. When implementing new technologies indicated in this work and optimizing the harvesting of plant biomass, the negative impact on the environment caused by stored municipal waste can be reduced. This biomass torrefaction process temperature and residence time were necessary for the design and construction of semi-pilot scale biomass torrefaction installations with dryer and torrefaction reactor to perform a continuous biomass torrefaction process using superheated steam

Parameter Identification for Lithium Ion Supercapacitor Based on a Modified RLS Method

As a kind of renewable energy source, lithium ion supercapacitors have bright prospects in national grids, new energy technologies and tram applications. It has the good features of high energy/power density, extremely low resistance, no demand for maintenance and long cycle life. In this paper, we build up the 2ndorder RC equivalent circuit model, which is based on the Thevenin equivalent circuit model. In order to improve the accuracy and stability, and achieve accurate identification of model parameters, such as OCV, R0, Rp1, Rp2, a variable forgetting factor method is introduced into the traditional fixed forgetting factor recursive least squares method. This provides a basic method and reference for the subsequent state estimation and life prediction of lithium ion supercapacitors. The accuracy of the model parameter identification method is verified by the experimental result.

IMPROVEMENT OF WEAR RESISTANCE OF SHREDDER BLADES USED IN A REFUSE-DERIVED FUEL (RDF) FACILITY BY PLASMA NITRIDING

Refuse-derived fuel (RDF) is a kind of renewable energy source to produce energy for replacement of fossil fuels. Aggressive working conditions in RDF facilities cause the shredder blades to wear out quickly. So, the purpose of this paper was to study the effect of plasma-nitriding process on wear resistance of shredder blades made of AISI D2 tool steel in the service condition of RDF facility. Shredder blades were commercially available from two different suppliers (A and B suppliers). These hardened shredder blades were plasma-nitrided in the mixed nitrogen and hydrogen atmosphere at a volume ratio of 3:1 at 450∘C for 12, 18 and 24[Formula: see text]h at a total pressure of 250 Pa. Characterisation of plasma-nitrided layers on the shredder blades was carried out by means of microstructure and microhardness measurements. Wear tests of plasma-nitrided shredder blades were performed under actual working conditions in the RDF facility. Wear analysis of these shredder blades was conducted using three-dimensional (3D) optical measuring instrument GOM ATOS II. The compositional difference of the shredder blades provided by A and B suppliers played an important role on the nitrided layer. The case depth of A-blades significantly increased with increasing plasma-nitriding time. However, the case depth of B-blades was fairly lower at the same nitriding time and only slightly increased with increasing plasma-nitriding time. Plasma-nitriding process significantly improved the surface hardness of the shredder blades. Maximum surface hardness values were achieved at nitriding time of 18 h for both blades. In this case, this increase in surface hardness values was above 100%. At nitriding time of 24[Formula: see text]h, the maximum surface hardness of A-blades significantly decreased, whereas this decrease in surface hardness of B-blades was the negligible value. The wear test results showed that plasma-nitriding process significatly decreased the wear of shredder blades; 18 h nitriding for A-blades and 24[Formula: see text]h nitriding for B-blades had better wear-reducing ability in the service condition of RDF facility. In these cases, the decreases in the total volume wear loss for A- and B-blades were 53% and 60%, respectively.

Analysis of usage of the renewable energy in Kyrgyzstan

The paper describes the analyses results of the possibility of using renewable energy in Kyrgyzstan. The research methodology development based on complex analysis of using kinds of renewable energy sources by conducted a preliminary survey of residences and semi-structured interviews with representatives from the local village administration. There has been analysed the potential energy of the solar, wind, river, biogas and geothermal sources. Generally, the geothermal sources are mainly concentrated in Issyk-kul region. The perspectives of their usage for energy supply is low due to poor-quality of heat resources. The available geothermal sources are used for medical purpose. Study outcomes provide information of using renewable energy sources for rational management of natural resources. Using renewable energy for Kyrgyzstan should be taken into account as a solution of population’s socio-economic problems in the decentralized region.

Comparative analysis of strong and weak acid pretreatment methods under pressurized and non-pressurized conditions for agro-industrial waste of apple pulp

It is well known that energy-related emissions have been increasing the global warming and pushing the climate change. In the face of this situation biomass-based biofuels, which is a kind of renewable energy source, are great alternatives instead of fossil derivative fuels. Moreover, biomass can be found easily and widely, which makes it an economical alternative. Biological conversation rate of the biomass to the biofuel is insufficient because of the molecular structure of the biomass. Pretreatment is required to increase the bioavailability of the biomass as the raw material. In this study, weak and strong acid pretreatments are studied under pressurized and non-pressurized conditions for apple pulp as biomass, which is an agro-industrial residue coming from industrial plants. Box-Behnken statistical design is used to determine the optimum level of some factors as time, chemical dose, and raw material dose. While the maximum total sugar concentration was found to be 23.71 g/L with sulfuric acid pretreatment, the reduced sugar concentration under pressurized conditions with strong acid pretreatment was found as 17.00 g/L.

Управление гибридным энергокомплексом на основе возобновляемых источников энергии разных видов

Управление гибридным энергокомплексом на основе возобновляемых источников энергии разных видов

Гибридная система децентрализованного электроснабжения на основе возобновляемых источников энергии разных видов

Гибридная система децентрализованного электроснабжения на основе возобновляемых источников энергии разных видов

Implementation of Biogas Stations into Smart Heating and Cooling Network

Abstract The paper is aimed at the description of implementation of a biogas station into software environment for the „Smart Heating and Cooling Networks”. The aim of this project is creation of a software tool for preparation of operation and optimization of treatment of heat/cool in small regions. In this case, the biogas station represents a kind of renewable energy source, which, however, has its own operational specifics which need to be taken into account at the creation of an implementation project. For a specific biogas station, a detailed computational model was elaborated, which is parameterized in particular for an optimization of the total computational time.

Impact analysis of RES-based DGs with economical considerations in restructured electricity market

ABSTRACTThe integration of distributed generators (DGs) into the grid is of great importance in improving system reliability. The criterion of minimizing total system cost used previously by many researchers for locating the optimal sites for DGs using optimal power flow (OPF) formulations was considered in this work. Here, three different cost functions are formulated for three kinds of renewable energy source (RES). Three different objectives were considered separately for determining the optimal locations for each kind of RES using the mixed integer non-linear programming (MINLP) method. Having many alternatives with these three objectives, the analytic hierarchy process (AHP) was used to reach a decision over getting the optimal locations for various kinds of RES. The proposed methodology was demonstrated on a 15-node distribution system.