Development and Test of Solutions to Enlarge the Power of PV Irrigation and Application to a 140 kW PV-Diesel Representative Case

The current state of the art of photovoltaic (PV) irrigation systems is limited to PV peak powers below 40 kWp, which does not cover the irrigation needs of farmers, co-operatives, irrigator communities, and agro-industries. This limitation of power is due to two main technical barriers: The quick intermittence of PV power due to the passing of clouds, and the maladjustment between PV production and water needs. This paper presents new solutions that have been developed to overcome these barriers and their application to the design and performance of a 140 kWp hybrid PV-diesel system for the drip irrigation of 195 ha of olive trees in Alter do Chão, Portugal. The performance of the solutions was analysed during two years of real operation. As the performance of the PV system is not only affected by intrinsic-to-design characteristics, but also by circumstances external to the system, new performance indices were developed. As an example, the percentage of use of PV electricity, PVSH, was 78% and 82% in 2017 and 2018, respectively, and the performance ratio of the PV part, PRPV, was 0.79 and 0.80. The economic feasibility was also analysed based on experimental data, resulting in savings in the levelized cost of electricity of 61%.

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Techno-economic feasibility analysis of a 3-kW PV system installation in Nepal

Renewables Wind Water and Solar ◽

10.1186/s40807-021-00068-9 ◽

2021 ◽

Vol 8 (1) ◽

Author(s):

Ramhari Poudyal ◽

Pavel Loskot ◽

Ranjan Parajuli

Keyword(s):

Net Present Value ◽

Meteorological Data ◽

Electric Energy ◽

Simulation Software ◽

Economic Feasibility ◽

Performance Ratio ◽

Energy Output ◽

Solar Pv ◽

Economic Returns ◽

Pv System

AbstractThis study investigates the techno-economic feasibility of installing a 3-kilowatt-peak (kWp) photovoltaic (PV) system in Kathmandu, Nepal. The study also analyses the importance of scaling up the share of solar energy to contribute to the country's overall energy generation mix. The technical viability of the designed PV system is assessed using PVsyst and Meteonorm simulation software. The performance indicators adopted in our study are the electric energy output, performance ratio, and the economic returns including the levelised cost and the net present value of energy production. The key parameters used in simulations are site-specific meteorological data, solar irradiance, PV capacity factor, and the price of electricity. The achieved PV system efficiency and the performance ratio are 17% and 84%, respectively. The demand–supply gap has been estimated assuming the load profile of a typical household in Kathmandu under the enhanced use of electric appliances. Our results show that the 3-kWp PV system can generate 100% of electricity consumed by a typical residential household in Kathmandu. The calculated levelised cost of energy for the PV system considered is 0.06 $/kWh, and the corresponding rate of investment is 87%. The payback period is estimated to be 8.6 years. The installation of the designed solar PV system could save 10.33 tons of CO2 emission over its lifetime. Overall, the PV systems with 3 kWp capacity appear to be a viable solution to secure a sufficient amount of electricity for most households in Kathmandu city.

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A review on the use of additive manufacturing to produce lower limb orthoses

Progress in Additive Manufacturing ◽

10.1007/s40964-019-00104-7 ◽

2019 ◽

Vol 5 (2) ◽

pp. 85-94 ◽

Cited By ~ 3

Author(s):

Mohammed S. Alqahtani ◽

Abdulsalam Al-Tamimi ◽

Henrique Almeida ◽

Glen Cooper ◽

Paulo Bartolo

Keyword(s):

Additive Manufacturing ◽

Lower Limb ◽

State Of The Art ◽

Production Costs ◽

Current State ◽

Research Challenges ◽

Fixation Devices ◽

Alignment Correction ◽

And Performance

Abstract Orthoses (exoskeletons and fracture fixation devices) enhance users’ ability to function and improve their quality of life by supporting alignment correction, restoring mobility, providing protection, immobilisation and stabilisation. Ideally, these devices should be personalised to each patient to improve comfort and performance. Production costs have been one of the main constraints for the production of personalised orthoses. However, customisation and personalisation of orthoses are now possible through the use of additive manufacturing. This paper presents the current state of the art of additive manufacturing for the fabrication of orthoses, providing several examples, and discusses key research challenges to be addressed to further develop this field.

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Integrated Simulation Environment for Unmanned Autonomous Systems—Towards a Conceptual Framework

Modelling and Simulation in Engineering ◽

10.1155/2010/736201 ◽

2010 ◽

Vol 2010 ◽

pp. 1-12 ◽

Cited By ~ 11

Author(s):

M. G. Perhinschi ◽

M. R. Napolitano ◽

S. Tamayo

Keyword(s):

Conceptual Framework ◽

State Of The Art ◽

Autonomous Systems ◽

Simulation Environment ◽

Integrated Simulation ◽

Systems Perspective ◽

Future Developments ◽

Current State ◽

And Performance ◽

Testing And Evaluation

The paper initiates a comprehensive conceptual framework for an integrated simulation environment for unmanned autonomous systems (UAS) that is capable of supporting the design, analysis, testing, and evaluation from a “system of systems” perspective. The paper also investigates the current state of the art of modeling and performance assessment of UAS and their components and identifies directions for future developments. All the components of a comprehensive simulation environment focused on the testing and evaluation of UAS are identified and defined through detailed analysis of current and future required capabilities and performance. The generality and completeness of the simulation environment is ensured by including all operational domains, types of agents, external systems, missions, and interactions between components. The conceptual framework for the simulation environment is formulated with flexibility, modularity, generality, and portability as key objectives. The development of the conceptual framework for the UAS simulation reveals important aspects related to the mechanisms and interactions that determine specific UAS characteristics including complexity, adaptability, synergy, and high impact of artificial and human intelligence on system performance and effectiveness.

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Assessment of Solar PV Potential and Performance of a Household System in Durban North, Durban, South Africa

10.21203/rs.3.rs-644597/v1 ◽

2021 ◽

Author(s):

Williams S. Ebhota ◽

Pavel Y. Tabakov

Keyword(s):

South Africa ◽

System Size ◽

Performance Ratio ◽

Solar Pv ◽

Pv System ◽

Simulation Tools ◽

Solar Pv System ◽

And Performance ◽

Module Type ◽

Rooftop Solar

Abstract A rooftop solar photovoltaic (PV) system is an alternative electricity source that is increasingly being used for households. The potential of solar PV is location dependent that needs to be assessed before installation. This study focuses on the assessment of a solar PV potential of a site on coordinates − 29.853762°, 031.00634°, at Glenmore Crescent, Durban North, South Africa. In addition, it evaluates the performance of a 6 kW installed capacity grid-connected rooftop solar PV system to supply electricity to a household. The results, obtained from PV design and simulation tools – PV*SOL, Solargis prospect and pvPlanner, were used to analyse and establish the site and PV system technical viability. The system’s configuration is as follows: load profile - a 2-Person household with 2-children, energy consumption − 3500 kWh, system size − 6 kWp, installation type - roof mount, PV module type - c-Si - monocrystalline silicon, efficiency − 18.9%, orientation of PV modules -Azimuth 0° and Tilt 30°, inverter 95.9% (Euro efficiency), and no transformer. The results show: meteorological parameters - global horizontal irradiation (GHI) 1659.3 kWh/m2, direct normal irradiation (DNI) 1610.6 kWh/m2, air temperature 20.6°C; performance parameters - annual PV energy 8639 kWh, Specific annual yield 1403 kWh/kWp, performance ratio (PR) 74.9%, avoided CO₂ emissions 5662 kg/year, and solar fraction 42.5 %. The analysis and benchmarking of the results show that the proposed solar PV system under the current conditions is technically viable for household electrification in Durban North, South Africa.

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Performance and Optimization of Commercial Solar PV and PTC Plants

International Journal of Recent Technology and Engineering - 2 ◽

10.35940/ijrte.e6247.018520 ◽

2020 ◽

Vol 8 (5) ◽

pp. 1703-1714 ◽

Cited By ~ 1

Keyword(s):

Clean Energy ◽

Economic Feasibility ◽

Operating Conditions ◽

Performance Ratio ◽

Design Parameters ◽

Optimal Size ◽

Solar Pv ◽

Levelized Cost Of Electricity ◽

Module Design ◽

Utility Scale

Installation of solar PV arrays at utility scale is gaining popularity nowadays because of the significant reduction in the cost of components as well as the global push towards clean energy. Solar PV plants along with Parabolic Trough Collector Solar thermal plants has the highest potential among the available Renewable Energy (RE) technologies existing in the world. The objective of this paper is to optimize the performance of commercial Solar PV and PTC power plant for a potential location and hence to arrive on a most feasible configuration for the site. A representative site located in the Abudhabi region of UAE considered for the study. This paper also details on the annual performance of the proposed plant along with its technical aspects. PVSYST 6.7.7 and SAM software is used to design the optimal size and its specifications of a 100MW PV grid connected system at Abu Dhabi (UAE) region. The design and arrangements of the system verified using simulation results. The annual energy generated from the designed utility-scale solar PV plant from PVSYST 6.7.7 calculated as 161198MWh/year with a performance ratio (PR) of 74.8% per year where as for PTC it has calculated as 157152MWh/year by using SAM. The STC (Standard Testing Condition) for the specification of PV modules are normalized operating conditions when testing the module. Design parameters such as module orientation, array yield, reference yield, final yield, global horizontal irradiation (GHI), and ambient temperature and loss factors evaluated. To evaluate the economic feasibility of proposed plant, the levelized cost of electricity (LCOE) is determined as $0.04404/kwh for Solar PV and as $0.01533/kwh for PTC, which is used to calculate lifecycle cost and energy production

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Design of Graphical User Interface Development Environment Software for sizing of Grid Connected Photovoltaic (GCPV) system

International Journal of Engineering & Technology ◽

10.14419/ijet.v7i3.15.17519 ◽

2018 ◽

Vol 7 (3.15) ◽

pp. 145

Author(s):

S Z.Mohammad Noor ◽

S Zaini ◽

A M.Omar

Keyword(s):

User Interface ◽

System Design ◽

Graphical User Interface ◽

Performance Ratio ◽

Specific Yield ◽

Pv System ◽

Development Environment ◽

Array Configuration ◽

Pv Module ◽

And Performance

This work presents a design of graphical user interface development environment (GUIDE) software for sizing of Grid Connected Photovoltaic (GCPV) system. The simulation model of the GCPV system design is developed by using GUIDE in MATLAB. The developed GUI display the performance of the PV system based on the three scenarios. The three scenarios are sizing based on architecture constraint, the energy required and budget constraint. The size of the GCPV system is from 4.6 kW to 60.0 kW. A GUIDE is developed to design and calculate the suitable size of photovoltaic (PV) module, analyses the optimum array configuration, selection of inverter, size of cable, determine the specific yield and performance ratio. The GUI be able to make a user’s job easier and beneficial in assisting the GCPV system design process compared to the manual calculation of the GCPV system.

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A Critical Appraisal of PV-Systems’ Performance

Buildings ◽

10.3390/buildings10110192 ◽

2020 ◽

Vol 10 (11) ◽

pp. 192

Author(s):

Zainab Usman ◽

Joseph Tah ◽

Henry Abanda ◽

Charles Nche

Keyword(s):

Renewable Energy ◽

Electric Energy ◽

Geographical Location ◽

Poor Performance ◽

Performance Ratio ◽

Energy Output ◽

Pv System ◽

Pv Systems ◽

Energy Technologies ◽

And Performance

Climate change and global warming have triggered a global increase in the use of renewable energy for various purposes. In recent years, the photovoltaic (PV)-system has become one of the most popular renewable energy technologies that captures solar energy for different applications. Despite its popularity, its adoption is still facing enormous challenges, especially in developing countries. Experience from research and practice has revealed that installed PV-systems significantly underperform. This has been one of the major barriers to PV-system adoption, yet it has received very little attention. The poor performance of installed PV-systems means they do not generate the required electric energy output they have been designed to produce. Performance assessment parameters such as performance yields and performance ratio (PR) help to provide mathematical accounts of the expected energy output of PV-systems. Many reasons have been advanced for the disparity in the performance of PV-systems. This study aims to analyze the factors that affect the performance of installed PV-systems, such as geographical location, solar irradiance, dust, and shading. Other factors such as multiplicity of PV-system components in the market and the complexity of the permutations of these components, their types, efficiencies, and their different performance indicators are poorly understood, thus making it difficult to optimize the efficiency of the system as a whole. Furthermore, mathematical computations are presented to prove that the different design methods often used for the design of PV-systems lead to results with significant differences due to different assumptions often made early on. The methods for the design of PV-systems are critically appraised. There is a paucity of literature about the different methods of designing PV-systems, their disparities, and the outcomes of each method. The rationale behind this review is to analyze the variations in designs and offer far-reaching recommendations for future studies so that researchers can come up with more standardized design approaches.

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Analysis and Performance of a Two-Axis PV Tracker in Southern Spain

Journal of Solar Energy Engineering ◽

10.1115/1.4003297 ◽

2011 ◽

Vol 133 (1) ◽

Cited By ~ 4

Author(s):

G. Almonacid ◽

E. Muñoz ◽

F. Baena ◽

P. Pérez-Higueras ◽

J. Terrados ◽

...

Keyword(s):

Southern Spain ◽

Performance Ratio ◽

System Behavior ◽

Average Yield ◽

Pv System ◽

Yield Increase ◽

Pv Systems ◽

Productivity Data ◽

And Performance ◽

The University

El Girasol, a two-axis photovoltaic (PV) tracker system of 9.6 kWp connected to the grid at the Campus of the University of Jaén in Southern Spain, has reached an average yield of 2092 kWh/kWp·year. As far as it is known, it is one of the highest productivity data reported up to now in PV systems. This paper presents a description of the system and the working analysis during 2 years of operation. Related to the system behavior, the following performances are highlighted: global efficiency of 10.4%, performance ratio of 73.1%, a yield increase versus a fixed and ideally faced PV system of 45.8%, and high operation reliability with minimal maintenance needs.

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Generating Adversarial Examples for Holding Robustness of Source Code Processing Models

Proceedings of the AAAI Conference on Artificial Intelligence ◽

10.1609/aaai.v34i01.5469 ◽

2020 ◽

Vol 34 (01) ◽

pp. 1169-1176

Author(s):

Huangzhao Zhang ◽

Zhuo Li ◽

Ge Li ◽

Lei Ma ◽

Yang Liu ◽

...

Keyword(s):

Programming Languages ◽

State Of The Art ◽

Source Code ◽

Natural Languages ◽

Current State ◽

Automated Processing ◽

Adversarial Examples ◽

Adversarial Training ◽

New Challenges ◽

And Performance

Automated processing, analysis, and generation of source code are among the key activities in software and system lifecycle. To this end, while deep learning (DL) exhibits a certain level of capability in handling these tasks, the current state-of-the-art DL models still suffer from non-robust issues and can be easily fooled by adversarial attacks.Different from adversarial attacks for image, audio, and natural languages, the structured nature of programming languages brings new challenges. In this paper, we propose a Metropolis-Hastings sampling-based identifier renaming technique, named \fullmethod (\method), which generates adversarial examples for DL models specialized for source code processing. Our in-depth evaluation on a functionality classification benchmark demonstrates the effectiveness of \method in generating adversarial examples of source code. The higher robustness and performance enhanced through our adversarial training with \method further confirms the usefulness of DL models-based method for future fully automated source code processing.

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Performance evaluation of building-integrated photovoltaic systems for residential buildings in southern India

Building Services Engineering Research and Technology ◽

10.1177/0143624419881740 ◽

2019 ◽

Vol 41 (4) ◽

pp. 492-506 ◽

Cited By ~ 5

Author(s):

P Ramanan ◽

K Kalidasa Murugavel ◽

A Karthick ◽

K Sudhakar

Keyword(s):

Tamil Nadu ◽

Residential Buildings ◽

Economic Feasibility ◽

Photovoltaic System ◽

Performance Ratio ◽

Building Structures ◽

Building Structure ◽

Pv System ◽

Building Integrated Photovoltaic ◽

Inclination Angles

The integration of photovoltaic modules into the building structure is a challenging task with respect to power generation of PV module and the effect of incident solar radiation. The performance of building integrated photovoltaic (BIPV) modules varies depending upon the orientation and azimuth angle of the building. In this work, the year-round performance and economic feasibility analysis of grid-connected building-integrated photovoltaic (GBIPV) modules is reported for the hot and humid climatic regional condition at Kovilpatti (9°10′0′′N, 77°52′0′′E), Tamil Nadu, India. The appropriate mounting structures are provided, to experimentally simulate the performance of GBIPV modules at various orientations and inclination angles (0° to 90°). The result indicated that the optimum orientation for installation of BIPV modules in the façade and walls is found to be east while that for a pitched roof south orientation is recommended. The overall average annual performance ratio, capacity utilisation factor, array capture loss and system losses are found to be 0.83, 23%, 0.07 (h/day), and 0.17 (h/day), respectively. In addition, the economic feasibility of grid connected PV system for residential buildings in Tamil Nadu, India is analysed using HOMER by incorporating both a net metering process and electricity tariff. Practical application: Grid-connected building-integrated photovoltaic system has many benefits and barriers by being installed and integrated into the building structure. The application of GBIPV in building structures and its orientation of installation needs to be optimised before installing into buildings. This study will assist architects and wider community to design buildings facades and roofs with GBIPV system which are more aesthetic and account for noise protection and thermal insulation in the region of equatorial climate zones. By adding as shading devices, they can reduce the need for artificial lighting, and moderate heating or cooling load of the buildings.

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