International Journal of Renewable Energy Technology (14 papers in press)
Heat loss analysis of three coil solar cavity receiver of parabolic dish collector under wind condition
by Ramola Sinha, Nitin.P Gulhane
Abstract: This paper consider a modified three coil solar cavity receiver and experimentally investigates the effect of increases in cavity inner wall area, fluid inlet temperature (50-80
Keywords: cavity receiver; heat Loss; thermal analysis; analytical modelling; wind test.
Novel Fuzzy-assisted Nonlinear Optimal power generation method for Grid-connected SPV System with TLBO optimization
by MANISHA , Sachin Bhati, Prerna Gaur, Diwaker Pathak
Abstract: This research article presents a novel fuzzy-assisted nonlinear proportional-integral (f-NPI) controller based optimal power generation method for a 100kW grid-connected solar photovoltaic (SPV) system with boost converter topology. The primary objective is to regulate power generation closer to its optimal point when variations in irradiance and/or temperature are experienced. f-PI and novel f-NPI based PV array reference current predictor is implemented to adjust the duty cycle for the converter. The gain parameters of controllers are being fairly tuned using Teaching-Learning based Optimization (TLBO) technique. A comprehensive simulation analysis is carried out using MATLAB R2017a, which verifies that the utilization of primitive parameters i.e. irradiance and temperature in the proposed controller results in enhanced performance in comparison to extant P&O and Fuzzy Logic Controller (using secondary/conventional parameters like voltage and current) in terms of settling time, efficiency and THD. Moreover, the operation of the novel f-NPI based method is found to comply with IEEE 929 standard.
Keywords: fuzzy system; solar photovoltaic system; renewable energy; grid-connected system; optimal power generation method; nonlinear controller; Teaching Learning-based optimization; power efficiency; Perturb & Observe; P&O; Total Harmonic Distortion; THD.
Non-linear management programing for grid connected hybrid system combined to E-mobility facility
by Mohamed Tabaa, Asmae Chakir, Fouad MOUTAOUAKKIL, Hicham Medroumi, Karim Alami
Abstract: The integration of renewable energy sources is a very essential point in the strategic list that has to be met by the different countries' governments to combat the constraints of the 21st century that the increased electricity demand in the residential sector represents the front-line constraints. However, the problem of intermittency inevitably arises. As a result, an optimal energy management represents the most intelligent solution to smooth energy profile during cases of extreme renewable production or critical energy shortages. Furthermore, in the second row the transport sector with major consumption of energy in a given country is regarded. For this reason, in a sense to reduce greenhouse gas emissions that threatens the environmental climate, the development of transportation electrification combined to households equipped with a grid connected PV-Wind-Battery hybrid system is investigated in this paper. In fact, to take advantage of the integration of renewable energy systems to residential sector as well as the notion of transport electrification the two notions are combined for electric vehicles with renewable energy charging. Indeed, the energy management of the global hybrid architecture is proposed via a non-linear programming algorithm and validated with MATLAB simulation.
Keywords: Hybrid renewable energy system; energy management; Electrical vehicle; E-mobility; Smart grid.
PERFORMANCE OF SELECTED ORGANIC WASTES FOR AVAILABLE TECHNOLOGIES FOR BIOGAS, KISUMU CITY-KENYA
by Peter Kabok, Frankline Otiende, Michael Oloko, George Ngusale
Abstract: Over years in cities to villages, inadequate and improper disposal of solid wastes exists, especially in Kenya (Africa) that lead to human and animal dumpsite scavenging, health problems, bad smell and unsightliness. The study tested performance of feacal, food and market (vegetables, fruits, tubers, cereals and green maize cobs) wastes for technologies or equipments available for biogas production (Fixed Dome Bio-Digester - FDBD, Flexible Structure Bio-Digester - FSBD, and Simple Ordinary Drum Bio - Digesters -SODBD) within Kisumu City/County. Only FDBD had known design parameter standards. The market waste were pre-prepared by chopping to sizes with own water content. Little water was added to food waste but feacal matter needed less water than 1:1 ratio used for cow dung; all were mixed to porridge consistency. The SODBD (1m3) produced gas in small quantities with high CO2 content. Match box lighting test at an outlet valve tube (25mm) was only positive for the market wastes. The 2.4 m3 FSBD and FDBD produced gas at 56% and 65% (within standards) from market waste and feacal matter feed stocks. The market waste thus suggested a natural co-generation bio-material. Need therefore arises for determining key parameters (for example caloric value, density and ratios) for feedstock in singular or mixed proportions for the digester systems size design. Manual preparation process here informs systems design automation, performance and management of the bio digesters. The available technology and bio material for biogas production is hence an option in managing particular city wastes but with digester design tailored to Bio material or mixture parameter characteristics for improvement of gas production.
Keywords: Design Parameters; Market Wastes; Technologies; Biogas; Performance.
Perception towards Rooftop Solar PV in India: Comparison between adopters and non-adopters
by Amitabh Satapathy, Arvind Jain, Sunil Barthwal
Abstract: The purpose of the study is to analyse the perception of consumers in India towards rooftop solar PV and find out if the difference in perception between adopters and non-adopters is a major reason for its poor adoption. It is surprising that growth in rooftop solar PV in India has been quite disappointing so far despite many obvious advantages. This paper through literature review found out five important factors of adoption for rooftop SPV and those are complexity, financial attractiveness, environment benefits, social image and trialability. On these five factors, the paper verified how the adopters perceive the rooftop solar PV in India compared to the non-adopters through statistical analysis of data collected through survey in the states of Kerala and Odisha in India.
Keywords: Rooftop; Solar PV; Perception; Adoption; Hypothesis.
Study on production, characterisation and utilisation of neem biodiesel as green fuel for compression ignition engine
by Bheru Lal Salvi, Sudhakar Jindal
Abstract: This work is aimed on preparation of neem (Azadirachta indica) biodiesel and its utilization in compression ignition engine. The neem bio-diesel (NB) was prepared by two stage trans-esterification and about 88% yield was obtained. The NB so obtained has higher viscosity and density, while slightly lower calorific value as compared to diesel. The blends of NB up to 20 vol.% (NB20) with petro-diesel were found to have nearly similar viscosity to that of petro-diesel. The study revealed that start of combustion was delayed, while the duration of combustion in degree crank angles increased with increase in NB in blends up to NB20. The use of NB20 had marginal effect on brake specific fuel consumption; the brake thermal efficiency is slightly improved, while smoke opacity decreased. The analysis of CO2 generated shows that use of NB20 led to savings in CO2 emission by 0.1414 kg per kWh of power generated.
Keywords: neem biodiesel; compression ignition engine; greenhouse gas; combustion; sustainable energy.
Design of low-cost solar powered water pump for Koh Dambang Village, Cambodia
by Kaustav Bharadwaz, Aayushi Misra, Avinash Venkat Bangaru, Prerona Kotoky, Murali Krishna Lakkam, Bhagavan Kusumanchi
Abstract: This paper proposes the development of a low-cost solar powered water pump (below US$50) for meeting the irrigation and household needs of the people of Koh Dambang, Cambodia. The geographical data, solar irradiance and water requirement data of Koh Dambang area was collected and analysed. The data helped in selecting a suitable pump and designing the solar panel accordingly. A 12 volts, 38 W DC powered centrifugal pump, powered by 12 volts, 50 W solar panel tilted at an angle of 15 degrees mounted on a flat surface was proposed for meeting the agricultural and household requirements of the people. The selected solar-powered water pumping system was priced at US$36 keeping in mind the cost consideration. The low cost solar-powered water pump appears to be a viable solution for the people of Koh Dambang owing to the ample sunlight which this region receives throughout the year.
Keywords: renewable energy; solar pump; Koh Dambang; solar irradiance; solar panel; Cambodia.
Biofuel and bioremediation prospects of estuarine diatoms
by G. Saranya, T.V. Ramachandra
Abstract: Escalating fuel prices, rising environmental concerns and dwindling stocks of fossil fuel have necessitated the exploration of viable alternative feedstocks. Biofuel from microalgae has been showing prospects of a viable alternative to conventional fossil fuels. The present study evaluates the bioremediation and biofuel potential of indigenously collected mixed consortia of estuarine diatoms, grown using aquaculture wastewater as the nutrient source. Diatoms, when subjected to different treatment conditions, exhibited better nutrients removal efficiencies (N: 89.1 ± 0.85%, P: 90.8 ± 0.12%) with significant variations in lipid content (14%-32%). Diatoms depicted real-time accumulation of neutral lipids during different phases of cell growth, observed through flow cytometry. Fatty acid profiling using GC-MS showed properties comparable to that of the plant-based oils. These results show the feasibility of growing diatoms in aquaculture wastewater and in vivo quantification of lipids using flow cytometry.
Keywords: microalgal (diatom) consortia; aquaculture wastewater; bioremediation and biofuel production; flow cytometry.
Assessment of the socio-cultural viability of integrated waste-to-energy systems for Uganda
by Miria Frances Agunyo, Kukunda Elizabeth Bacwayo, Sarah Kizza-Nkambwe
Abstract: Application of waste-to-energy systems could be the solution for urban areas in countries like Uganda where municipal solid waste is composed of atleast 70% organic matter and sewage and faecal sludge management is limited to about 20 treatment plants. Projected increase in urbanisation to 50% in 2050 will only constrain the existing sanitation facilities, resulting in public health issues and competition for land use. This study investigates application of integrated waste-to-energy systems consisting of a combination of anaerobic digestion, incineration and composting to treat organic waste streams from urban areas. Despite the benefits of such systems related to resource recovery in form of biogas and organic fertiliser, little is known about their socio-cultural viability. A survey carried out at Uganda Christian University showed respondent's beliefs and cultural backgrounds influenced their attitude towards utilising resources recovered. Also, sensitisation and quality assurance of resources recovered boosted system acceptability.
Keywords: socio-cultural viability; integrated waste to energy systems; waste energy; digestate; biogas.
Special Issue on: ICONRER-2019 Emerging Trends in Renewable and Sustainable Energy
Performance improvement of Savonius turbine by design modifications: A review
by Amit Mandal, Kunj Bihari Rana, Brajesh Tripathi
Abstract: Savonius turbine is a vertical axis wind turbine with a huge potential of harnessing wind energy. For utilizing wind energy, horizontal axis wind turbine is a commonly used machine. The use of vertical axis wind turbines is not common due to their poor efficiency compared to horizontal axis wind turbine. The researches in the direction of performance improvement by design modifications have increased in recent years. Present review incorporates the latest advancements in design modifications of Savonius wind turbines for performance improvement. It is observed that, the power and torque coefficients of Savonius turbine can be improved by two ways i.e., by flow augmentation and negative torque reduction. This paper summarizes the various types of modifications applied over Savonius rotor for performance improvement.
Keywords: Wind energy; Vertical axis wind turbine; Savonius turbine; Blade profile; Flow augmentation; Efficiency improvement.
A computational fluid dynamics study of condenser for condensation of bio-oil vapour from fast pyrolysis of biomass
by Tanushree Soni, B.L. Salvi
Abstract: In this work, a computational fluid dynamics (CFD) study of shell and multi-tube condenser with baffle plates was done for flow visualization and improved heat transfer for condensation of biomass vapour. The water as cooling fluid was circulated through tubes and bio-oil vapour as inlet hot fluid was passed through condenser shell. The CFD model was validated with the experimental results of newly designed and developed condenser for fractional condensation of bio-oil vapour. It was observed that use of baffle plates in the condenser shell diverted the vapour flow direction and increased the path of travel, which would result into improved heat transfer. Furthermore, for the fractional condensation, single shell with baffle plates and multi-outlets was sufficient instead of using two or more condensers. Overall, the study is more dedicated for inside flow visualization of biomass vapour flow and improvement in the baffle plates placing and orientation.
Keywords: CFD analysis; Shell and tube condenser; condensation; baffle plate; bio-oil vapour.
Parametric Analysis of Scheffler Concentrator with Convex Receiver for Direct Steam Generation
by Dnyaneshwar Malwad, Vinod Tungikar
Abstract: In this work, Scheffler dish with improved design of the receiver is used for direct steam generation. Experiments were conducted from February to May 2019, for monthly performance assessment of 16 m2 Scheffler concentrator. Effect of varying aperture area, solar beam radiation, ambient temperature and wind speed on the thermal efficiency of the system is investigated. The average receiver temperature at focus observed to be 323oC with average beam radiation 656 W/m2. From the results, the Thermal efficiency of the system is reduced by 2.36% with a decrease in aperture area from 12.82 to 9.59 m2. The average thermal efficiency of the system decreased linearly from 57.29% to 39.99% with an increase in wind speed from 0.5 to 6 m/s where as it reduced by 1.13% with an increase in ambient temperature from 24oC to 46oC.
Keywords: Scheffler dish; beam radiation; aperture area; direct steam generation; monthly performance; thermal efficiency.
Design and Implementation of Interleaved High Gain dc-dc Converter
by VINOD SHRIVASTAVA
Abstract: dc-dc converters playing a vital role in solar power system. They reduce the problem of shadow effect on solar panel. Different converter topologies help to reduce the shadow effect. This research paper showing a topology for high voltage gain. In this paper presents two topologies of dc-dc converter for high gain with fewer ripples on output side. Topology 1 is related to single stage amplification with various components, while topology 2 presents double stage amplification. The proposed topology 2 gives voltage gain of about 12 and the efficiency of this converter is about 85%. This converter is designed for 34 V input and 407 V output. This topology has been also compared with two existing topologies with voltage gain, efficiency and voltage ripples. A 224 Watt, 34V input and 407V converter has been developed in this paper.
Keywords: high step-up; boost converter; single stage amplification; double stage amplification; interleaved converter.
To Inspection of SPV Coupled IEEE 14 Bus System during Fault Condition
by Riaz Israni
Abstract: In this technical paper, IEEE 14 Bus system is connected with SPV (Solar Photovoltaic) system. This interconnection of SPV and IEEE 14 Bus system is evaluated during fault condition. In this paper synchronous generator is replaced by SPV unit. Primarily, SPV system of 40MW capacity is connected at bus 2 at the place of 40 MVA synchronous generator. When fault occur on any of the transmission line of IEEE 14 bus system, then system becomes unstable for short time duration. IEEE14 bus works on 60Hz frequency. SPV has ability to fluctuate output power which depends on input temperature and irradiation of solar. By varying temperature and solar irradiation of SPV, output power may oscillate, but to build constant output power we assume SPV to be under Standard Test Condition (STC). During fault condition, output of SPV may disturb and this observational study is the main purpose of this paper. The IEEE 14 bus system has three synchronous condensers (to maintain power factor) and one slack bus. When SPV is coupled with IEEE 14 bus, then quality of power is reduced due to harmonic in SPV system. To reduce harmonic, filter system is used.
Keywords: IEEE 14 Bus system; SPV system; synchronous generator; Bus 2; Standard Test Condition.