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Numerical procedures and their practical application in PV modules’ analyses. Part II: Useful fractions and APE

T. Rodziewicz M. Rajfur
Opto-Electronics Review | 2019 | vol. 27 | No 2 | 149-160
Keywords Sunlight irradiance spectrum Sunlight irradiance intensity Irradiance APE UF Solar power Solar power industry Photovoltaics
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Abstract

The article regards aspects of PV modules tested with the use of natural sunlight. The analysis of spectral structure of solar energy resources in southern Poland, carried out on the basis of meteorological data originating from SolarLab PW Wrocław and AGH Kraków, Poland [1] was used in the article. It is a continuation of the article: Analysis of solar energy resources in southern Poland for photovoltaic applications [1], describing the method to determine spectral parameters of average photon energy (APE) and useful fraction (UF) with the use of a solar radiation spectrum simulator. This article, however, includes an experimental presentation of their impact on PV conversion of modules with different absorbers. Theory and practice of the measurements were described with the use of spectral parameters such as: UF, APE. Their influence on the efficiency of modules’ photovoltaic conversion with various spectral characteristics of absorbers was presented. The most recent methods described, which characterise the structure of solar energy resources such as annual distributions of APE and UF, have not been commonly used yet in Poland and other countries, even though they most precisely define adjustment of the spectral factor to the selected PV module.

Practical application of UF, in detection of absorber type used in the tested PV module/cell is demonstrated in the final part of the article.

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Authors and Affiliations

T. Rodziewicz
M. Rajfur

Numerical procedures and their practical application in PV modules analyses. Part I: air mass

T. Rodziewicz M. Rajfur
Opto-Electronics Review | 2019 | vol. 27 | No 1 | 39-57
Keywords Sunlight radiation spectrum Sunlight radiation intensity Radiation Solar power Solar power industry
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Abstract

The subject of the article is aspects of PV modules and cells measurement, with the use of natural sunlight. A light source is an important element during calibration and measurements of solar cells and modules. All designers of artificial light sources try to recreate natural light using so called measurement tables. The correctly performed measurement, i.e. meeting all the appropriate atmospheric conditions, guarantees obtaining the result with the use of a reference spectrum. The article has two main aims. The first aim of the article is to answer the question asked earlier - if the sunlight spectrum registered in appropriate conditions is so good that it serves as the reference spectrum - then, in practice, during measurements carried out with its use, certain problems occur regarding the correct measurement results or their interpretation. The second aim regards presenting detailed numeric procedures in order to enable readers to associate air mass with geographical coordinates and Local Solar Time of their study/laboratory location. Moreover, having the data from their local meteorological station, they will be able to estimate the occurrence of the measurement spectral error of the tested cell/module not only from the group referred to in the article but also for others, for which they have a dedicated characteristics of spectral response.

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Authors and Affiliations

T. Rodziewicz
M. Rajfur

Load regulation application of university campus based on solar power generation forecasting

Guozheng Han Shujuan Tan Zihan Zhang
Archives of Electrical Engineering | 2023 | vol. 72 | No 2 | 429-441 | DOI: 10.24425/aee.2023.145418
Keywords load regulation solar power generation forecast photovoltaic generation
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Abstract

For a solar photovoltaic power system on a university campus, the electricity generated by the system meets the campus load, and the extra electricity is delivered to the grid. Generally, the price of the photovoltaic system is cheaper than that of the utility power system. The full use of solar electricity can reduce the electricity cost of the school. The deep belief network is used to predict solar photovoltaic generation and electricity load, and the gap is found. According to the gap, the power loads on the campus are adjusted to improve the utilization rate of solar power generation. Through the practical application of Changqing Campus of Qilu University of Technology in China, it is found that the utilization rate of solar photovoltaic power generation effectively improved from 91.24% in 2017 to 98.16% in 2019, and the annual electricity is saved by 68 610 yuan (in 2019).
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Authors and Affiliations

Guozheng Han
1
ORCID: ORCID
Shujuan Tan
1
ORCID: ORCID
Zihan Zhang
1
ORCID: ORCID
  1. School of Information and Automation Engineering, Qilu University of Technology (Shandong Academy of Sciences), No. 3501, Daxue Road, Changqing District, Jinan 250353 Shandong Province, PR China

Regulatory policy of renewable energy sources in the European national economies

Viktor Koval Yevheniia Sribna Sylwester Kaczmarzewski Alla Shapovalova Viktor Stupnytskyi
Polityka Energetyczna - Energy Policy Journal | 2021 | vol. 24 | No 3 | 61-78
Keywords renewable energy „green” tariff preferential taxation state regulation of renewable energy solar power plants
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Abstract

The article analyzes and evaluates the development of renewable energy from the standpoint of state regulation and incentives. It is noted that the global production of renewable electricity has increased by 15% over the last year. The periods of introduction of the “green tariff” as an economic stimulus for the development of solar energy, which became the starting point for the development of alternative generation in different countries, are analyzed. The role of institutional factors in the development of renewable energy, such as the free issuance of licenses for electricity generation, stimulating the creation of specialized research areas, technology development and production of relevant equipment, was observed. The necessity of taking into account the regional peculiarity in the state stimulation of the development of renewable energy is proved. The economic efficiency of the state regulation of alternative energy in time measurement per conditional unit of alternative renewable energy stations was calculated, taking the coefficient of proportionality into account. Therefore, the calculation indicates the high effectiveness of government policy in regulating energy in terms of only short-term lag (α = 1.3) and the number of stations 80 percent of full saturation relative to the basic needs of energy consumption. A separate further stage in the development of renewable energy without the introduction and expansion of the “green tariff” has been identified. This approach was introduced in Poland, which ensured the country not only the inflow of foreign investment, but also the formation of free competition among investors.
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Authors and Affiliations

Viktor Koval
1
ORCID: ORCID
Yevheniia Sribna
2
ORCID: ORCID
Sylwester Kaczmarzewski
3
ORCID: ORCID
Alla Shapovalova
4
Viktor Stupnytskyi
5
  1. National Academy of Sciences of Ukraine, Ukraine
  2. National University of Water and Environmental Engineering, Ukraine
  3. Mineral and Energy Economy Research Institute Polish Akademy of Sciences, Kraków, Poland
  4. V.I. Vernadsky Taurida National University, Ukraine
  5. Dubno Branch Higher Education Institution «Open International University of Human Development «Ukraine», Ukraine

The design of a model for a 1 MW parabolic trough concentrated solar power plant in Sudan using TRNSYS software

Abdelkareem Abdallah Abdelkareem Jebreel Hamad Mohamed Ali Hamad
Polityka Energetyczna - Energy Policy Journal | 2022 | vol. 25 | No 3 | 67-90
Keywords thermal storage thermal solar collectors photovoltaic solar panel renewable source of energy solar power plants
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Abstract

Solar photovoltaic (PV) and concentrated solar power (CSP) systems are the present worldwide trends in utilizing solar energy for electricity generation. Solar energy produced from photovoltaic cells (PV) is considered the main common technology used due to its low capital cost; however, the relatively low efficiency of PV cells has spotlighted development and research on thermal engine applications using concentrated solar power. The efficiency of concentrated solar power is greater than that of PV and considering the solar potential for Sudan. Therefore, this study has been performed in an attempt to draw attention to the utilization of CSP in Sudan since the share of CSP is insignificant in comparison with PV, besides the suitability of CSP applications to Sudan’s hot climate and the high solar energy resource, the study presents a design model of 1 MW parabolic trough collectors (PTC) using the Rankine cycle with thermal energy storage (TES) in Sudan, by adopting reference values of the Gurgaon PTC power plant in India. The design of a 1 MW Concentrated Solar thermal power plant using parabolic trough collectors (PTC) and thermal energy storage is proposed. The simulation was performed for a site receiving an annual direct normal irradiance (DNI) of 1915 kWh/m2, near Khartoum. The results showed that the plant can produce between nearly 0.6 to 1 MWh during the year, and around 0.9 MWh when it encompasses thermal energy storage with an average thermal efficiency of 24%. These results of the PTC Power plant encourage further investigation and the development of CSP technologies for electricity generation in Sudan.
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Authors and Affiliations

Abdelkareem Abdallah Abdelkareem Jebreel
1
ORCID: ORCID
Hamad Mohamed Ali Hamad
2
  1. Sapienza Università di Roma, Italy
  2. University of Khartoum, Sudan

An experimental study on parabolic trough collector in simulated conditions by metal-halide solar radiation simulator

Bartosz Stanek Łukasz Bartela Daniel Węcel Sebastian Rulik
Archives of Thermodynamics | 2022 | vol. 43 | No 3 | 47-61 | DOI: 10.24425/ather.2022.143171
Keywords Solar simulator Parabolic trough collectors Parabolic trough collectors testing Concentration solar power
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Abstract

The utilization of solar radiation to obtain high-temperature heat can be realized by multiplying it on the illuminated surface with solar concentrating technologies. High-temperature heat with significant energy potential can be used for many technological purposes, e.g. the production of heat, cold or electricity. The following paper presents the results of the experimental study, on the operation of the parabolic linear absorber in the parabolic concentrator solar system. The parabolic mirror with an aperture of 1 m and a focal length of 0.25 m focuses the simulated radiation onto a tubular absorber with a diameter of 33.7 mm, which is placed in a vacuum tube. The length of the absorber is 1 m. The installation is illuminated by the solar simulator, which allows to carry out tests under constant and repeatable conditions. The simulator consists of 18 metal halide lamps, with a nominal power of 575 W each with a dimming possibility of up to 60%. The paper presents preliminary results of heat absorption by the analysed absorber, temperature increment, collected heat flux, and the pressure drop crucial for the optimization of the absorber geometry.
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Authors and Affiliations

Bartosz Stanek
1
Łukasz Bartela
1
Daniel Węcel
1
Sebastian Rulik
1
  1. Silesian University of Technology, Department of Power Engineering and Turbomachinery, Konarskiego 18, 44-100, Gliwice, Poland

A Solar-Powered Fertigation System Based on Low-Cost Wireless Sensor Network Remotely Controlled by Farmer for Irrigation Cycles and Crops Growth Optimization

P. Visconti R. de Fazio P. Primiceri D. Cafagna S. Strazzella N.I. Giannoccaro
International Journal of Electronics and Telecommunications | 2020 | vol. 66 | No 1 | 59-68 | DOI: 10.24425/ijet.2019.130266
Keywords precise farming IoT devices fertigation system sensors solar-powered WSN data processing electronic boards
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Abstract

Nowadays, the technological innovations affect all human activities; also the agriculture field heavily benefits of technologies as informatics, electronic, telecommunication, allowing huge improvements of productivity and resources exploitation. This manuscript presents an innovative low cost fertigation system for assisting the cultures by using dataprocessing electronic boards and wireless sensors network (WSN) connected to a remote software platform. The proposed system receives information related to air and soil parameters, by a custom solar-powered WSN. A control unit elaborates the acquired data by using dynamic agronomic models implemented on a cloud platform, for optimizing the amount and typology of fertilizers as well as the irrigations frequency, as function also of weather forecasts got by on-line weather service.

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Authors and Affiliations

P. Visconti
R. de Fazio
P. Primiceri
D. Cafagna
S. Strazzella
N.I. Giannoccaro

Landscape Protection around the Pobiedziska Solar Park

Paweł Szumigała Karolina Szumigała
Teka Komisji Urbanistyki i Architektury Oddziału Polskiej Akademii Nauk w Krakowie | 2022 | vol. L | 203-229 | DOI: 10.24425/tkuia.2022.144851
Keywords solar power plant landscape management agricultural landscape rural landscape green screens
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Abstract

The construction of large solar parks requires dedicated landscaping methods. Solar parks — colloquially called photovoltaic farms or solar power plants — require landscape conservation measures to be implemented in the areas adjacent to these projects. This is an extremely important issue for sustainable development and the protection of cultural assets and identities, including the rural landscape. The aim of this work is to present the possibilities of landscape protection using the example of the planned solar park in the municipality of Pobiedziska in the Greater Poland Voivodeship. The studies use case studies, qualitative and quantitative analyses and in situ tests. The studies covered the planned investment area of 160 ha and the adjacent areas. The project proposals for landscape protection applied in this case — ‘green protection walls’ — were presented. The measures presented make it possible to preserve open-air landscapes in agricultural and rural areas from the point of view of sustainable development and the protection of cultural assets, and their formula, adapted to the landscape, can be applied to a large extent and can be dedicated to the local conditions in rural areas.
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Authors and Affiliations

Paweł Szumigała
1
Karolina Szumigała
1
  1. Poznań University of Life Sciences, Department of Green Areas and Landscape Architecture

Feasibility study for the implementation of solar power plants in the USA

Volodymyr Mykhaylovych Mamalyga Oleh Oleksandrovych Prytulenko
Polityka Energetyczna - Energy Policy Journal | 2024 | vol. 27 | No 1 | 67-80
Keywords implementation renewable energy sources solar power plants Feasibility study Calculation methodology
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Abstract

The article provides calculations and feasibility study of solar power plants implementation for the states of New Jersey, New Mexico and Michigan. The average cost for grid power, average household kwh use per month and average cost for 6-kw system with 26% federal tax credit applied were taken into account. The approach outlined in this article proposes to take into account changes in the value of money, tariffs and period of service of solar power plant.
The conducted research shows that the construction of SPPs in the USA can be profitable in the conditions of constant growth in prices for electricity produced using traditional energy sources. However, with the stability of electricity prices, the use of solar energy is far from the most profitable investment.
It has been proven that there is a need to focus on the research of the latest energy storage and generation technologies in order to reduce the impact of the instability of renewable energy production on the stability of power grids in the future. Further development of SPPs can help increase their availability and competitiveness, which will contribute to the creation of a sustainable and green energy infrastructure. The development of technologies in this area will also lead to a decrease in installation prices and an increase in the efficiency of the panels.
The main limitation of solar power plants is the need for a large area for the installation of panels in order to achieve the level of industrial electricity production. Therefore, now the centralized production of electricity using the sun is possible only in areas that are unsuitable for life and economic activity.

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Authors and Affiliations

Volodymyr Mykhaylovych Mamalyga
1
ORCID: ORCID
Oleh Oleksandrovych Prytulenko
1
ORCID: ORCID
  1. Educational and Research Institute of Institute of Nuclear and Thermal Energy, National Technical University of Ukraine “Igor Sikorsky Kyiv Polytechnic Institute”, Ukraine

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