scholarly journals Roof’s Potential and Suitability for PV Systems Based on LiDAR: A Case Study of Komárno, Slovakia

2020 ◽  
Vol 12 (23) ◽  
pp. 10018
Author(s):  
Marcela Bindzarova Gergelova ◽  
Zofia Kuzevicova ◽  
Slavomir Labant ◽  
Stefan Kuzevic ◽  
Diana Bobikova ◽  
...  

The case study focuses on evaluating the suitability of roof surfaces in terms of their solar potential based on their geometric parameters. The selected processing methodology detects segments of roof surfaces from the LiDAR base, supplemented with spatial information (orthophoto map, real estate cadastre (REC)—footprint, basic database for the geographic information system (ZBGIS)—classification of buildings—current use). The approach based on spatial analyses takes into account the limit conditions for determining the impact of solar radiation resulting from the roof area, slope, aspect, and hillshade. Considering to the available subsidy scheme for family houses in the conditions of the Slovak Republic, a narrower sample of 35 family houses was selected from the total number of typologically represented buildings (194). A 3D model of the building created by combining REC and LiDAR substrates shows the roof surface without overlap, while another 3D model made of LiDAR substrates alone represents the actual dimension of the roof surface. The results presented for each selected building show good agreement with each other, and their visualizations were obtained using two GIS environment approaches. In the area of family houses, up to 94% of the roof areas of buildings registered in the REC meet the conditions for the installation of a PV system with an output of 2.6/3.3 kW.

Author(s):  
M. K. Firozjaei ◽  
M. Makki ◽  
J. Lentschke ◽  
M. Kiavarz ◽  
S. K. Alavipanah

Abstract. Spatiotemporal mapping and modeling of Land Surface Temperature (LST) variations and characterization of parameters affecting these variations are of great importance in various environmental studies. The aim of this study is a spatiotemporal modeling the impact of surface characteristics variations on LST variations for the studied area in Samalghan Valley. For this purpose, a set of satellite imagery and meteorological data measured at the synoptic station during 1988–2018, were used. First, single-channel algorithm, Tasseled Cap Transformation (TCT) and Biophysical Composition Index (BCI) were employed to estimate LST and surface biophysical parameters including brightness, greenness and wetness and BCI. Also, spatial modeling was used to modeling of terrain parameters including slope, aspect and local incident angle based on DEM. Finally, the principal component analysis (PCA) and the Partial Least Squares Regression (PLSR) were used to modeling and investigate the impact of surface characteristics variations on LST variations. The results indicated that surface characteristics vary significantly for case study in spatial and temporal dimensions. The correlation coefficient between the PC1 of LST and PC1s of brightness, greenness, wetness, BCI, DEM, and solar local incident angle were 0.65, −0.67, −0.56, 0.72, −0.43 and 0.53, respectively. Furthermore, the coefficient coefficient and RMSE between the observed LST variation and modelled LST variation based on PC1s of brightness, greenness, wetness, BCI, DEM, and local incident angle were 0.83 and 0.14, respectively. The results of study indicated the LST variation is a function of s terrain and surface biophysical parameters variations.


Author(s):  
Ahmed A Khalil ◽  
Kamal G Metwally ◽  
Nasser Z Ahmed

The principal aim of this paper is to analyze the impact of rubber pad systems on levels of vibrations and values of stresses and deformations induced in the subway tunnel segments. Thus, the 3D model has been selected to be isotropically simulated in the ANSYS program to conduct a finite element analysis. Therefore, the proposed track system in the tunnel of line 4 of the Greater Cairo Metro has been selected as an analytical and simulation case study. The impact of using eight different values for the stiffness of the rubber pad system in the case of a single tunnel has been analyzed. The results showed that levels of vibrations are significantly affected and are in logarithmic correlation with the stiffness. Also, the impact of the stiffness on the deformations and stresses are determined as well as mathematical models connecting the different parameters have been introduced.


Electronics ◽  
2019 ◽  
Vol 8 (12) ◽  
pp. 1443 ◽  
Author(s):  
Abdullah Alshahrani ◽  
Siddig Omer ◽  
Yuehong Su ◽  
Elamin Mohamed ◽  
Saleh Alotaibi

Decarbonisation, energy security and expanding energy access are the main driving forces behind the worldwide increasing attention in renewable energy. This paper focuses on the solar photovoltaic (PV) technology because, currently, it has the most attention in the energy sector due to the sharp drop in the solar PV system cost, which was one of the main barriers of PV large-scale deployment. Firstly, this paper extensively reviews the technical challenges, potential technical solutions and the research carried out in integrating high shares of small-scale PV systems into the distribution network of the grid in order to give a clearer picture of the impact since most of the PV systems installations were at small scales and connected into the distribution network. The paper reviews the localised technical challenges, grid stability challenges and technical solutions on integrating large-scale PV systems into the transmission network of the grid. In addition, the current practices for managing the variability of large-scale PV systems by the grid operators are discussed. Finally, this paper concludes by summarising the critical technical aspects facing the integration of the PV system depending on their size into the grid, in which it provides a strong point of reference and a useful framework for the researchers planning to exploit this field further on.


BioResources ◽  
2020 ◽  
Vol 15 (3) ◽  
pp. 5913-5925
Author(s):  
Miloš Gejdoš ◽  
Marek Trenčiansky ◽  
Blanka Giertliová ◽  
Martin Lieskovský ◽  
Zuzana Danihelová

Sales of timber, which represent the main source of forest management income, are essential for the economic welfare of forest businesses. Planning the timber sale management faces a certain amount of uncertainty and risk in such difficult conditions of climate change. Model scenarios make preparation for potential future development possible. The aim of the study was to create a prediction model of coniferous and non-coniferous sawlogs for the area of the Central Europe. The objective of the model was to estimate the variations in the price of coniferous or non-coniferous sawlogs following a linear regression equation in the analysed time series from 2001 to 2017. The price of coniferous sawlogs was significantly affected in a negative way by the amount of incidental fellings and in a positive way by the Gross Domestic Product. The price of the non-coniferous sawlogs was significantly affected in a positive way by the GDP and the volume of non-coniferous sawlog export. These factors caused a non-elastic response of the coniferous sawlog price. The impact of these factors depends to a great extent on the wood species composition of the forests in the Slovak Republic. The model also can be set for conditions of other countries when considering their economic indicators.


Energies ◽  
2020 ◽  
Vol 13 (7) ◽  
pp. 1668 ◽  
Author(s):  
German Osma-Pinto ◽  
María García-Rodríguez ◽  
Jeisson Moreno-Vargas ◽  
Cesar Duarte-Gualdrón

The intermittent injection of power and the nature of power electronic devices used for photovoltaic (PV) systems can affect the power quality (PQ) of the grid to which they are connected. This study proposes to quantify and evaluate the impact of PV injection on the PQ of a low-voltage (LV) network by applying a statistical analysis through hypothesis testing for the mean comparison of populations of parameters with and without a PV system. The effects of PV power injection and load demand at the point of common coupling on PQ are monitored. The methodology includes the selection and monitoring of PQ, the use of a matrix for classification of data with similar load and PV power injection conditions, and the application of the Wilcoxon rank sum test. This methodology was applied to evaluate the impact of a 9.8 kWp PV system on the PQ of an LV network.


Author(s):  
Mahmoud Ismail

Performance ratio is one of the indicators used to describe the effectiveness of the PV systems. The sustainability of the PV system year after year as well as its reliability can be checked by measuring the performance ratio each year. This indicator will also enable us to carry out a comparison between the performances of different PV systems. In this paper, the performance ratios for five PV systems installed on the roof tops of some of PTUK university buildings have been calculated on monthly and yearly basis. The analysis has been carried out using the available data (energy production and solar irradiation) for the year 2019. It was found that the performance ratio has higher values for May and September in comparison with other months. On the other hand, its lowest values were obtained in winter months. This trend can be observed for all of the PV clusters on the five buildings.  When taking into account the overall system, the highest value for the performance ratio was 0.89, which was for September, whereas its lowest value of 0.70 was obtained in January. The performance ratio, which was calculated on yearly basis for the overall system, was found to be 0.80. When considering each building separately, the lowest value was 0.44 for the “Services” building whereas the highest value was 0.94 for the Science building.


2015 ◽  
Vol 9 (2) ◽  
pp. 156-175 ◽  
Author(s):  
Domenico Campisi ◽  
Donato Morea ◽  
Elisa Farinelli

Purpose – The purpose of this paper is to evaluate the expected cost of a large-sized photovoltaic (PV) system (= 1 MW) in reaching grid parity, not taking into account any type of government incentives (now quite uncommon in industrialized countries). A PV system located in Southern Italy will be the subject of this assessment. Design/methodology/approach – The paper presents the case of a 1 MW ground-mounted PV system. The data regarding solar radiation on the surface of the modules and the relative solar diagrams were simulated and reported using PVSYST® 5.21 software. To evaluate the profitability and solvency of the project, a number of factors were taken into consideration: profitability indicators of net present value and internal rate of return, the debt service coverage indicators of debt service cover ratio and loan life cover ratio and their mean annual values (annual debt service cover ratio and annual loan life cover ratio, respectively). A sensitivity analysis with respect to the most critical element (weighted average cost of capital) gave strength to the results. Findings – The achievement of grid parity for 200 kW PV systems is happening globally in areas with higher irradiation, but it clearly refers to residential utilities and is not applicable to large systems. The case study considers a power plant (= 1 MW) to assess the total cost that it would need to have to be economically advantageous. Research limitations/implications – This is an assessment made using a case which, given an average irradiance value in the area and the energy produced, can be used in all countries lying in the temperate zone. For other areas, a scaling coefficient would be needed. Practical implications – The paper is useful for understanding the order of cost, which must catch up to PV technology to make investments in power plants profitable in the absence of government incentives. It is also helpful for those who make government policies so that these may propose possible incentives commensurate with the actual difference between the value of the technology and the value of the investment. The study is also useful for a possible comparison with a system sharing the same characteristics (size, energy production) for off-grid use and customers. Originality/value – The study can be a valuable support for government policies to incentivate PV systems that contribute to a reduction of greenhouse gases and that help contain climate change. The case study represents a real case taken directly from a real project. This case study and its sustainable features have not been previously presented in a scientific journal.


2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Yunlin Sun ◽  
Siming Chen ◽  
Liying Xie ◽  
Ruijiang Hong ◽  
Hui Shen

Northwest China is an ideal region for large-scale grid-connected PV system installation due to its abundant solar radiation and vast areas. For grid-connected PV systems in this region, one of the key issues is how to reduce the shading effect as much as possible to maximize their power generation. In this paper, a shading simulation model for PV modules is established and its reliability is verified under the standard testing condition (STC) in laboratory. Based on the investigation result of a 20 MWp grid-connected PV plant in northwest China, the typical shading phenomena are classified and analyzed individually, such as power distribution buildings shading and wire poles shading, plants and birds droppings shading, and front-row PV arrays shading. A series of experiments is also conducted on-site to evaluate and compare the impacts of different typical shading forms. Finally, some feasible solutions are proposed to avoid or reduce the shading effect of PV system during operation in such region.


Energies ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1746
Author(s):  
Luka Budin ◽  
Goran Grdenić ◽  
Marko Delimar

The world’s demand for electrical energy is increasing rapidly while the use of fossil fuels is getting limited more and more by energy policies and the need for reducing the impact of climate change. New sources of energy are required to fulfill the world’s demand for electricity and they are currently found in renewable sources of energy, especially in solar and wind power. Choosing the optimal PV nominal power minimizes the unnecessary surplus of electrical energy that is exported to the grid and thus is not making any impact on the grid more than necessary. Oversizing the PV system according to the Croatian net-metering model results in switching the calculation of the costs to the prosumer model which results in a decrease of the project’s net present value (NPV) and an increase in the payback period (PP). This paper focuses on formulating and solving the optimization problem for determining the optimal nominal power of a grid-connected PV system with a case study for Croatia using multiple scenarios in the variability of electricity production and consumption. In this paper, PV systems are simulated in the power range that corresponds to a typical annual high-tariff consumption in Croatian households. Choosing the optimal power of the PV system maximizes the investor’s NPV of the project as well as savings on the electricity costs. The PP is also minimized and is determined by the PV production, household consumption, discount rate, and geographic location. The optimization problem is classified as a quadratically constrained discrete optimization problem, where the value of the optimal PV power is not a continuous variable because the PV power changes with a step of one PV panel power. Modeling and simulations are implemented in Python using the Gurobi optimization solver.


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