International Journal of Renewable Energy Technology (25 papers in press)
Comparative study of performance and emission characteristics of a CI engine using blends of corn oil methyl ester (COME) with diesel fuel
by Dinesh Kumar Sharma, Ram Kumar Agrawal
Abstract: The rapidly increasing demand of energy and depletion of fossil fuel resources lead to renewable energy developments such as vegetable oils, animal fats and their derivatives. Biodiesel derived from vegetable oils such as their methyl esters and ethyl esters are promising as performance parameters are comparable with diesel fuel and exhaust emissions are lower than that of diesel fuel. In the present work, methyl ester of corn oil is prepared by transesterification using methanol. The physical and chemical properties of corn oil methyl ester (COME) are comparable with diesel fuel. Tests have been carried out to evaluate performance and emission characteristics of a compression ignition (CI) engine using COME100 and its blends (COME25, COME50 & COME75) with diesel fuel. The acquired data are compared and analyzed under different load conditions for the diesel fuel.
Keywords: diesel engine; biodiesel; corn oil methyl ester.
Corrective load shedding using fuzzy decision tree approach for real time voltage security enhancement of power system
by Sanjiv Kumar Jain, Narayan Prasad Patidar, Yogendra Kumar
Abstract: The paper proposes a novel algorithm for optimal load shedding using fuzzy decision tree. The presented algorithm is computationally efficient and can be utilised for on-line voltage security enhancement. It is based on Fuzzy Decision Tree. To avoid the voltage collapse condition and the system status is in non-correctable emergency, the final remedy is load shedding. Due to the feature selection approach of decision trees the method is fast enough for on-line load shedding of power system. The scheme is based on the notion of the static voltage stability margin. The vigorous classification of potential samples is simple due to the advantage of decision tree. The work presents the load shedding approach for all credible line outages. Classification of voltage security is done initially using test cases after the training of decision tree (DT). Which is further tested for secure and insecure status of the power system. The result shows the fast and accurate conversion of insecure cases to secure cases for a credible contingency condition. The initial database is prepared by wide variations of loading conditions at all the load buses using traditional approach of continuation power flow method. The effectiveness of the proposed algorithm of load shedding is tested using IEEE-30 bus system. The power management system applicability of the presented methodology is quite suitable for on-line control decisions to restore the power system in secure condition after disturbances.
Keywords: Continuation power flow (CPF),Credible contingencies; Fuzzy decision tree (FDT); Optimal Load shedding; Power system security; Voltage collapse,.
Interval Type-2 Fuzzy Logic Based MPPT Algorithm for Direct Drive PMSG Wind Turbine System
by Hanafy Hassan, Haitham Yassin, Mohab Hallouda
Abstract: This paper proposes a maximum power point tracking (MPPT) scheme for direct drive permanent magnet synchronous generator (PMSG) wind turbine system. In this scheme, the machine side converter (MSC) is controlled using the interval type-2 fuzzy logic control (IT2-FLC). The IT2-FLC is proposed owing to its ability to handle the uncertainties of the system parameters. The additional degree of freedom of type-2 fuzzy sets is due to the third dimension in the membership function which handles power oscillations damping and voltage recovery following parameter uncertainties in the network. The field oriented control is used to control the machine side and grid side converter. The design of the proposed control scheme of the MSC is presented in this paper.rnSimulation results, based on MATLAB-SIMULINK, for a 1.5 MW PMSG wind turbine are carried out to validate the proposed control scheme considering the various uncertainties. Also, experimental results, with hardware in loop (HIL) configuration, are obtained for reduced scale PMSG wind turbine to demonstrate the feasibility of the controller for real time applications. The results show a significant enhancement in speed regulation, mechanical stress reduction, and power harvest with the proposed control scheme.rn
Keywords: Interval type-2 fuzzy logic control (IT2-FLC); Permanent magnet synchronous generators (PMSG); Maximum Power Point Tracking (MPPT).
Experimental Investigation of the a Solar Cooker based on Evacuated Tube Collector with Phase Change Thermal Storage unit in Indian Climatic Conditions
by Avadhesh Yadav, Sanjeev Kumar, Ashish Kumar
Abstract: Solar cooker based on evacuated tube collector with phase change thermal storage unit is investigated. In this experimental setup, solar cooker with phase change thermal storage unit is attached with evacuated tube collector. The water is used as a working fluid, and it is filled in the evacuated tubes. During daytime, acetanilide (phase change material) stores solar energy throughout the sunshine hours. The energy stored by the phase change material during the daytime can be transferred to the cooking vessel entirely throughout the day up till the late evening time. Daytime and evening cooking processes are carried out separately at different loads. To enhance the performance of the solar cooker, the reflector is used beneath the evacuated tube collector. It is observed that in case of the high load, the solar cooker gives better performance with reflector as compared to without reflector. The maximum increase in the temperature of the working fluid, phase change material and cooking vessel with reflector is 18.3%, 20.4% and 20.8% respectively. Also, the cooking time is reduced to 30 minutes with the reflector. It is found that evening cooking using phase change material heat storage unit is faster than daytime cooking at low load.
Keywords: Thermal Performance; Evacuated tube collector; solar cooker; Phase change material.
Reliability assessment of a remote hybrid renewable energy system using Monte Carlo Simulation
by Sarangthem Sanajaoba, Eugene Fernadez
Abstract: Hybrid renewable energy systems have become a promising alternative for supplying power to remote locations because of the various negative environmental impacts caused by the conventional generating units. The reliability of power supply from such hybrid energy system is of prime concern owing to the stochastic power output from renewable energy sources. Unlike conventional generating units, the reliability aspects of a hybrid energy system are to be treated differently. System reliability depends on various factors such as the wind speed, solar radiation, load demand, wind turbine generator force outage rate (FOR) and hardware status of photovoltaic panels. In this context, a realistic simulation models for the reliability assessment of a remote hybrid energy system with battery storage is presented. The reliability analysis is conducted through Monte Carlo simulation to evaluate the loss of load expected (LOLE) reliability index. Finally, the proposed models are tested in a remote case study area.
Keywords: Hybrid energy system;Renewable energy; Solar photovoltaic; wind turbine generator; battery storage; Reliability; Monte Carlo simulation; Loss of load expected; Wind speed; Solar radiation.
Special Issue on: RESRB 2016 Research Development and Business of Renewable Energy Technologies
PERFORMANCE ANALYSIS OF DIFFERENT CONFIGURATIONS OF HEATING AND COOLING FOR A MULTIZONE BUILDING
by Saba Arif, Muzaffar Ali
Abstract: Multi zone HVAC designing is important as considerable amount of the worlds energy is used for heating, ventilation, and air conditioning (HVAC) systems used in multi zones. Hospitals are one of most critical multi zone buildings. So, proper designing of multi zone building will lead toward high savings in energy. Key step towards this goal is development of simulation based analysis approach for performance analysis of different air distribution systems. There is huge diversity in HVAC configurations used in commercial and residential sector which makes it difficult to model. Most common types of configurations are; constant volume with reheat, dual duct and Variable Air Volume (VAV) system, which is commonly found in large commercial buildings. Objective of this research is to investigate the impact of operational zoning and HVAC system operation strategies on energy performance of hospitals by maintaining comfort conditions. Load is calculated for each zone and optimized for creating multi zone building. Then after proper designing of central system, different HVAC configurations are designed for a hospital building. Afterwards, Energy simulation is used for forecasting best air distribution system for a multi zone building. Therefore; this research aims to simulate air distribution systems for energy saving potential for a hospital building in climate of Pakistan by developing different models in TRACE 700. Results show that COP of absorption chiller is highly dependent on components temperatures and out to be 0.78 in current research. Additionally, cooling capacities and NPV cash flow is determined for all three air distribution systems. According to results of economic analysis and cooling capacities, 52 ton load and required cfm in each zone is fulfilled by dual duct configuration in most efficient manner for multi zone buildings such as hospitals.
Keywords: Multi zone building; Air conditioning; energy; TRACE 700; NPV; Thermal comfort; VAV; CAV; dual duct.
Dome with dripping lateral pipe-fabricated solar water heater
by Mallikappa D.N, Vishwanath Nayak, Eshwa Raih
Abstract: This work deals with the design and fabrication of the semicircular solar water heater to use non-conventional energy to obtain hot water. The solar water heater has been made by using locally available materials like dripping lateral pipe, coconut coir, plastic drum, galvanized iron sheet, hose pipes etc. Work has been done on three types of set-ups. Experimentation has been carried out for the period two months. In the performance evaluation, inlet, outlet temperature of the water and the drum water temperature has been measured. Experimental investigation has been carried out by using three different trial setups, Semicircular setup without insulation and heat absorber plate, Semicircular setup with insulation and galvanized iron cover as a absorber, results are not favorable for getting hot water in both the cases. The setup with insulation blackened galvanized iron cover and transparent plastic cover which covers the pipes gives good amount of hot water. The maximum temperature attained in this set-up is 72 degrees. The water flow takes place due to thermo siphon effect.
Keywords: lateral pipe semicircular solar water heater; solar hour angle; instantaneous radiation; Dripping pipe.
Special Issue on: New and Renewable Energy Resources
Evaluation of Optical Efficiency of an All-Glass ETC using Ray Tracing Technique
by Tarun Kumar Aseri, Chandan Sharma, Ashish Kumar Sharma, Doraj Kamal Jamuwa, Rohit Misra
Abstract: Hot water is required for various industrial process heating applications and daily domestic needs. Majority of the industrial process heating applications requires hot water in the temperature ranges of 60
Keywords: Evacuated tube collector; optical efficiency; ray tracing.
A Comparative Study of Oxygenated Additives for Diesel in Compression Ignition Engine
by Chandan Kumar, K.B. Rana, B. Tripathi, Ashish Nayyar
Abstract: Performance improvement and emissions control are quite difficult to handle simultaneously in diesel engines. These two tasks can be achieved by one of the methods such as: engine design improvement, engine exhaust treatment and modification in fuel. The modification of fuel using additives is most feasible approach to control the high emissions without deteriorating the engine performance. The aim of this paper is to present the comprehensive review and comparative study of oxygenated additives with respect to engine performance and emission characteristics. It is concluded from literature review that oxygenated compounds are the most suitable and economical among all additives available for this purpose.
Keywords: C.I. engine; diesel; additive; emission; performance.
Anaerobic digestion of grass-cuttings under mesophilic and regulated digester pressure
by Ishmael Matala Ramatsa
Abstract: The successful functioning and stability of an anaerobic digester depends on the interplay of several factors, each of which is very important to the success of the system as a whole. pH is central to the whole system as it dictate the survival for the bacteria. In this study the effect of digester pressure was investigated at a fixed temperature of 36oC. The digester pressure was manipulated using back pressure regulator. Grass cuttings were used as feed material to the digester. Three pressures of 2bar, 4bar and 6bar were investigated for a period of 10 days. The characteristics and methane yield achieved when digesting grass cuttings under constant digester pressure (gauge pressure) suggested that it is possible to produce biogas that has minimal amount of CO2.The highest methane compositions at 0bar, 2bar, 4bar and 6bar were 55.77, 62.2, 65.8 and 71.2% and carbon dioxide compositions were 58.85, 35.2, 32.5 and 26.2%.The amount of CO2 decreased significantly with increased pressure and the pH values dropped to 7.01, 6.96 and 6.78 respectively with increase in pressure.
Keywords: Regulated pressure; pH; ammonia-nitrogen; methane; inert gases.
Comparative Performance Analysis of an SI Engine with Treated and Raw Biogas
by Amit Jhalani, Shyamlal Soni, Dilip Sharma, Pushpendra Kumar Sharma
Abstract: The study investigates the comparative performance of a single cylinder SI engine operated on treated and raw biogas. The methane content of this gas is utilized as the fuel.The biogas is treated with different methods before fuelling in the engine and hence the performance of the engine is compared. The raw biogas is treated for removal of moisture and H2S because H2S is poisonous in nature and moisture lowers the power output and may corrode engine parts. In this work, CaCl2 and silica gel were used separately for the absorption of moisture. Activated carbon and iron chips were used for the elimination of H2S. The results revealed that the increase in efficiency depends on the type of treatment given to raw biogas. Moreover, scrubbing of moisture had a greater impact as compare to the H2S removal. Effect of biogas treatment on engine emissions is also studied.
Keywords: Biogas; SI Engine; Purification of biogas; Alternative Fuel; Renewable.
Preparation and Characterization of Cao nanoparticle for biodiesel production from mixture of edible and nonedible oils
by Jharna Gupta, Madhu Agarwal, AJAY KUMAR Dalai, S.P. Chaurasia
Abstract: Calcium Nitrate (CaO/CaN) and Snail shell (CaO/SS) were successfully utilized for the development of CaO nanoparticle and used in biodiesel synthesis from a mixture of edible and nonedible oils. These solid base heterogeneous catalysts were characterized by FT-IR, XRD, and TGA techniques. DebyeScherer equation also calculated the average crystalline size of a nanometer. The comparable catalytic activity of CaO/CaN and CaO/SS catalyst was also studied for biodiesel production and found the increment of biodiesel yield from 88% to 92% using CaO/SS. The used optimum reaction conditions were: 6wt% catalyst loading, 65
Keywords: Biodiesel; snail shell; transesterification; mixture of oils.
Wavelet and Hilbert Huang Transform Based Wind Turbine Imbalance Fault Classification Model Using K-Nearest Neighbor Algorithm
by Hasmat Malik, S. Mishra
Abstract: Wind turbine (WT) is a key part in wind power generator system (WTGs). For proper operation, condition monitoring and fault diagnosis is a major part in WTGs. In this paper, three different types of nacelle yaw faults along with healthy condition are analyzed using wavelet Transform (WT) and Hilbert Huang Transformed (HHT) based k-Nearest Neighbor (k-NN) algorithm. For decomposing the raw signals, discrete approximation of Meyer wavelet function (DMeyer/ dmey) is used and to extract the feature, Hilbert Huang Transform is used to find the amplitude and phase feature of decomposed signal. k-Nearest Neighbor algorithm based classifier is designed for classifying faults based on extracted features. Prepared feature matrix of twenty one attributes is used for wind turbine nacelle yaw imbalance fault classification. Proposed technique is being compared with other computational intelligence dependent techniques of artificial neural network network (i.e. multilayer perceptron-MLP). Results and different comparisons of proposed technique could work as an essential tool for fault diagnosis of WTGs.
Keywords: dmey wavelet transform; Wind turbine; Feature extraction; Hilbert Huang transformation; k-nearest neighbor
algorithm; Fault diagnosis.
Techno-Economic Scrutiny of HRES through GA and PSO Technique
by Yashwant Sawle, S.C. Gupta, Aashish Kumar Bohre
Abstract: Presented work analyses the feasible sizing of two different hybrid renewable energy systems (HRSE) are PV-Wind-Biomass hybrid systems and PV-Wind hybrid systems. The proposed system includes battery unit for storage purpose and diesel generator for reliable operation. The electricity price or cost of energy (COE) is minimized as objective function to decide the optimal solution of hybrid system using GA and PSO. The optimal size of HRES is selected based on the lowest value of COE. The optimal solution includes high reliability, maximum value of renewable fraction, less emission and low penalty cost according to minimum COE. The maximum value of loss of power supply probability (LPSP) is assumed 2% in this case study for reliability analysis. This paper aims to present the techno-economic feasibility of above mentioned HRES for a remote area of Jamny Ven Village barwani district, India. The optimization results are evaluated through load following and cycle charging dispatch strategy furthermore the results are also compared using GA and PSO optimization techniques. Hence, the main purpose of presented work is to compare the performance results of GA & PSO with minimization of COE using load following and cycle charging dispatch strategy.
Keywords: Hybrid renewable energy system; dispatch strategies; COE; LPSP; penalty cost; pollutant emission.
Performance of Generalized Unified Power Flow Controller (GUPFC) in Transmission System
by RAJAREDDY DUVVURU, B. VENKATA PRASANTH, V. GANESH
Abstract: This manuscript focuses on innovative dynamic representation of power electronics based on generalized unified PFC (power flow controller). The GUPFC is a Voltage Source Converter (VSC) based Flexible AC Transmission System (FACTS) controller used to provide series and shunt compensation among the multi transmission line systems of a substation. GUPFC improves the performance of power quality issues, active and reactive power oscillations in multiple transmission lines. This paper proposes a complete replica comprising of 48-pulse Gate Turn-Off (GTO) thyristor based VSC which examines the dynamic operation of control scheme for shunt and two series VSC for voltage stabilization and active and reactive power compensation by using POD controller among the transmission lines of the grid network. The total digital simulation of shunt VSC which is operating as a Static Synchronous Compensator (STATCOM) and able to control the voltage at bus and two series VSC which is operating as a Static Synchronous Series Capacitor (SSSC) which is able to control injected voltage, at the same time as keeping injected voltage in quadrature with current within the power system is completely modelled in MATLAB/SIMULINK.
Keywords: 48-pulse GUPFC; Power Oscillation Damping; Power Quality.
A modeling and analysis of exhaust gas recirculation system to lower the NOx emission from internal combustion engine: a review on advanced and novel concepts
by Zulfukar Ali Ahmed, Dinesh Kumar Sharma
Abstract: Internal combustion (IC) engines emit harmful gases such as HC, CO2, and NOx etc. In terms to avoid serious effects like global warming, researchers are rigorously working towards identification of options to lower these. Search is on for better alternatives to the fossil fuels to propose clean and green fuels. Possibility of engine hardware modifications are also being tried to lower the emission of these harmful gases to environment. NOx is a very toxic gas element of this family, which is responsible for very horrible effects such as acid rain, water quality deterioration, ground level ozone, and visibility impairment.
Uses of vegetable oil as fuel, water injection, exhaust gas recirculation (EGR) and after treatment technique are the basic way to minimize the NOx emission which is too much harmful, exhausted from IC engine. EGR technique is worldwide technique to reduce the NOx emission by diluting the fresh charge with recirculation of some amount of exhaust gas, which results in lowering the maximum temperature of internal combustion engine. However, its use also reflects in terms of reduced brake thermal efficiency and more smoke emission. Study shows that proper optimization can be helpful for minimizing the emission of NOx without much effecting with the performance of Internal Combustion engine.
In the present review, modeling and analysis of different types of EGR have been reported and compared. Out of them, analytical results favor the use of long route (LR) EGR over short route (SR) EGR and hybrid EGR. Long route EGR is capable to fulfill desired outcome with practical use also by lowering the heat losses in the engine with the help of intercooler.
Keywords: exhaust gas recirculation; exhaust emission; global warming.
SOLAR SORPTION COOLING FOR RESIDENTIAL AIR-CONDITIONING APPLICATIONS
by Julia Aman, Paul Henshaw, David Ting
Abstract: This paper presents the comparison of two sorption cooling systems for providing air conditioning in a residential building that can be driven by a flat plate solar collector. A thermodynamic model has been developed for each system to compare the energy balance in each component and the coefficient of performance (COP). Analyses have been performed for 10 kW water-ammonia absorption and activated carbon-ammonia adsorption chillers. For both systems, the first law efficiencies have been compared and the optimum efficiency has been investigated under different operating conditions. Analysis revealed that under any operating condition, the COP is always higher for the absorption chiller and its maximum value is 0.6, which is almost twice that of the adsorption chiller (COP=0.35), for 10 kW systems operating at evaporator and condenser/absorber temperatures of 2oC and 30oC, respectively. The adsorption system requires a higher energy input to produce the same cooling effect as compared to the absorption system.
Keywords: air conditioning; absorption; adsorption; ammonia; activated-carbon; energy; COP.
Optimal Conditioning Monitoring of Wind Turbines Using Intelligent Image Processing and Internet of Things
by Sujatha Kesavan
Abstract: The aim is to suggest a control scheme for the wind mills which convert wind energy to electrical energy. The functioning of the governing scheme is characterized by incorporating it to a Doubly Fed Induction Generator (DFIG). The stationary part of the DFIG is unswervingly linked to the electric network. The rotating part is allied to this electric network all the way through a back-to-back AC-DC-AC PWM converter. Fuzzy logic is used to acquire features using decision making logic which as human-like flexibility. The FLC provides a crisp and smooth control action. The governing process of the converter on rotating part is comprehended by stationary magnetic flux to adjust the performance of the Fuzzy Logic Controller (FLC). The FLC is opted to have an intelligent speed control. To enable a level direct current voltage and to guarantee a pure sine wave for the current in the grid side a Grid Side Converter (GSC) is used which is controlled using FLC. The accuracy of the FLC used for the control of DFIG has a quick vibrant retort with almost unsteady error value once evaluated with the scheme using conformist Proportional Integral (PI) controller. Image processing algorithms are used to track the blade sweep and angular velocity. The entire monitoring is implemented using ATmega processor and incorporated in cloud service for online monitoring.
Keywords: Doubly Fed Induction Generator (DFIG); Fuzzy Logic Controller; Power Converters; Image processing ; Internet of Things.
Structural, morphological and electrical characterization of rGO-P3HT composite film for photovoltaic applications
by Prakash Chandra Mahakul, Pitamber Mahanandia
Abstract: Interesting properties like low cost processing, green, flexible, solution processable etc. of organic semiconductors have attracted the attention of researcher for the next generation optoelectronics applications. Reduced graphene oxide (rGO) has been prepared by modified Hummers method followed by reduction using hydrazine hydrate as reducing agent. RGO incorporated Poly[3-hexylthiophene-2,5-diyl] (P3HT) composite films has been fabricated processing followed by spin coating method using 1,2-dichlorobenzene as solvent. Structural and morphological characterization of the composite film has been analyzed by XRD, SEM and FESEM. The reduced graphene oxide (rGO) was observed to be well dispersed in the polymer matrix. Functional characteristics and interaction between filler and host P3HT matrix has been studied by Fourier transform infrared spectroscopy (FTIR) and Raman characterization. An increase in electrical conductivity has been observed for the rGO incorporated film. Applicability of the composite for different optoelectronic devices has been illustrated by using cyclic-voltammetry characterization. Improvement in electrical characteristics of the composite can be attributed to rGO network in the composite films.
Keywords: Reduced graphene oxide (rGO); poly[3-hexylthiophene-2,5-diyl] (P3HT); 1.2-dichlorobenzene; dispersion; cyclic-voltammetry.
To Study the effect of glucose feeding rate for sustainable voltage generation from microbial fuel cell containing wastewaters
by Payel Choudhury, Rup Narayan Ray, Tarun Kanti Bandyopadhyaya
Abstract: The sustainable voltage generation was extensively experimented through semi batch using isolated pure microorganism. Though higher voltage generation of 911 mV can be possible through optimization of process parameters by batch fermentation. However, sustainable power generation was not found in batch process. Therefore, the potential influence of several parameters for voltage generation was addressed by semi continious fermentation process. In this present work sustainable voltage generation (550 mV) was achieved through fed batch mode when initial glucose was kept 8 g/L in the production medium. However, 18g/L of glucose (25 ml) was consecutively fed at interval of 72 and 108 h during semi continious fermentation
Keywords: MFC; fed batch; optimization; voltage.
Design of Solar Photovoltaic Energy Generation System for Off-Grid Applications
by NEHA ADHIKARI
Abstract: This paper presents the design and control of a standalone solar-PV (PhotoVoltaic) energy generating system using an isolated half bridge boost dc-dc converter. The adaptive methodology based INC (Incremental Conductance) method is used with the PI (Proportional Integral) controller for MPPT (Maximum Power Point Tracking) control. A voltage controller and current regulator are designed for VSI using a cascade loop control to maintain the power quality at the consumer load end. The proposed system with its controllers is modelled in Matlab/Simulink and its performance is evaluated under varying solar radiations as well as varying consumer loads.
Keywords: Adaptive INC MPPT Controller; Closed loop controller; DC-DC converter; Maximum power point tracking; Solar photovoltaic.
A Comprehensive Review of Biodiesel and CNG as Alternative Fuels for Compression Ignition engine
by SUDHIR KUMAR PATHAK, Ashish Nayyar, Chandan Kumar
Abstract: In search of alternative fuels for compression ignition (CI) engines, several experimental and review studies have been done in the last few decades. This paper presents a comprehensive review of the production, performance and emissions of biodiesel and compressed natural gas (CNG) as an alternative to fossil-based diesel fuel for CI engines. The properties of biodiesel and CNG, produced from different sources and their fatty acid composition have also been addressed. The summary of the experimental set-up used by different researchers for the studies and performance and emissions characteristics of CI engines with biodiesel is present in this paper. The complete impression of this paper is that the performance of the engine slightly deteriorates with the use of biodiesel and CNG partially instead of diesel, but the emissions are significantly improved. The impressive cetane number and the inherent oxygen of biodiesel enhance the combustion process which leads to reductions in HC, CO and smoke formation. When CNG is using as an alternative fuel the soot and NOx emissions are decreasing for CI engines.
Keywords: Biodiesel; Alternative fuels; CNG; Emission; Smoke; Nox.
Fault Current Contribution and Short Circuit Behaviour of a Solar PV Integrated Distribution Network
by Pramod Kumar Bhatt, Sudhir Y. Kumar
Abstract: Abstract: The aim of this paper is to analyse the short circuit (SC) behaviour and fault level due to solar PV integration in a smart distribution network. In order to investigate the issue, a generic urban distribution feeder is modelled, which supplies power to the load of varying nature. The network is analysed according to IEC 60909 standard and the alteration in SC current and fault level due to various types of faults is reported. Paper also reports the variation in SC current due to the grid strength and neutral grounding techniques. It is found that, with solar PV integration, the major change in fault level occurs due to the three phase fault then followed by double line to ground and other faults. Moreover, the varying network conditions also alter the SC current and fault level of the system. Such situation has to be managed to ensure the protection coordination and reliability of the system. The integration of more and more renewable energy sources like solar PV is expected in future power grid, therefore a proper planning study is required at the time of integration to ensure the reliable operation of the system.
Keywords: Fault current; solar integration; distribution network; weak grid; SC behaviour; fault MVA.
Influence of Nozzle opening pressure on Combustion, Performance and emission analysis of waste cooking oil biodiesel fueled Diesel Engine
by RAJESH KUMAR, R.P. Gakkhar Gakkhar
Abstract: Biodiesel is the esters of fatty acids which has been proved the best alternative to overcome the problem of quick depletion of fossil fuel with time and environmental degradation. Virgin vegetable and fat oil cannot be directly used in CI engines due to very high viscosity and density of oil. Hence transesterification process is adopted to reduce the viscosity of the oil. As the lower blends Biodiesel can be easily used in a diesel engine without any modifications. But in order to use neat biodiesel or its higher percentage blends, injection system modification is required to overcome the problems arise due to higher viscosity and density of biodiesel. In the present work, biodiesel was produced using waste cooking oil as raw oil. Biodiesel and its B20 blend were used as a fuel in a diesel engine to analyse and compare combustion, performance and emission characteristics with reference to conventional diesel fuel. Experiments were performed at load variation of 25%, 50%, 75% and 100% and at 2000 rpm speed by varying the nozzle opening pressure. The standard nozzle opening pressure of the engine was 225 bar. The injection pressure was increased from 225 bar to 235 bar. The start of combustion takes place earlier as the percentage of fuel blend ratio increases which is mainly due to shorter ignition delay. The maximum peak cylinder pressure was lower in biodiesel and its B20 blend. Improvement in brake specific fuel consumption and brake thermal efficiency was observed for B100 and B20 as compare to diesel fuel. CO, HC and smoke opacity were slightly decreased in case of biodiesel and its blend as nozzle opening pressure increases. The Very small increase in NOx emission was observed for B100 and B20.
Keywords: Waste cooking oil Biodiesel; Diesel engine; Nozzle opening pressure; Performance; Emission.
Special Issue on: Sustainable Energy Technologies
STUDIES ON HYDROGEN FUELLED STATIONARY C. I. ENGINE OPERATED END-UTILITY SYSTEM
by Vinod Singh Yadav, Dilip Sharma, S.L. Soni
Abstract: The refineries turned in a better performance with their cumulative 181 million tones crude throughput, almost 7 per cent more than the previous fiscals achievement and a little over 2 percent of the planned target. The world is presently confronted with the twin crisis of fossil fuel depletion and environmental degradation. Combined residential and commercial energy demand is expected to increase in order to meet the expected increase in electricity demand as the worlds population shall grow and more people shall move to urban areas with access to electricity. The search for an alternative fuel, which promises a pleasant link with sustainable development, energy conservation, management, efficiency, and environmental safeguarding, has become highly noticeable in the present context. rnIn this investigation, fresh air with hydrogen enrichment was used as intake charge in a C. I. engine. Experiments were conducted on a 1-C, 4-S, air-cooled, stationary direct-injection diesel engine (Kirlosker TAF1) with maximum 1500 rpm and maximum 4.4 kW capacity coupled to an electrical generator. The injection timing (17
Keywords: Hydrogen-Enrichment; Injection timing; Flow rate of hydrogen; Performance.