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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
331

Profilerad PV-modul AvSammansatta Kiselceller / Profiled PV-module of Cut Silicon Cells.

Cortes, Sebastian January 2021 (has links)
I denna rapport presenteras en analys av en profilerad solmodul av sammansatta kiselceller. Syftet med detta är att undersöka effektkurvan och I-V diagram på en denna solmodul vid olika infallsvinklar från ljuskällan för att få en förståelse på förluster gentemot en plan-modell. Genom att konstruera en modell med skurna kiselsolceller utgörs mätningar för att få en representation av effektkurvan. Resultatet skall sedan jämföras med en plan-modell, därefter diskuteras resultaten från bägge modellerna.
332

ENERGIANALYS AV FASTIGHETEN ANDERSLUND 12 : Energieffektiviseringsmöjlighet med solceller

Andersson, Alexander, Lindström, FAHRIYE Cennet January 2021 (has links)
Today's society is dependent on energy and the increasing use of energy affects the environment in a negative way. In Sweden, homes and premises account for 39% of total energy use. Achieving national environmental quality goals requires a reduction in energy use and the energy saving potential in the real estate sector is large. Energy use in buildings can be reduced by carrying out certain energy efficiency measures. Kårhuset by Mälardalen University was built in 1997 and it is a gathering place for students. The building is located on the campus area in Västerås and includes an office, restaurant kitchen, dining room, pub and meeting rooms for line associations. In this work, an energy survey has been carried out by the property Anderslund 12 (Kårhuset) to find out the current energy use and investigate the energy saving potential in the building.  The work's literature study analyzes previous research and similar case studies. Thereafter, the building's energy use has been simulated by IDA ICE by creating a basic model in the software using data from various authorities and site visits. The results of the basic model were then compared with simulations of various energy efficiency measures to evaluate the energy saving potential. The measures examined are window replacement, additional insulation of exterior walls and replacement of heat exchangers in the air handling units. As a complementary alternative, energy efficiency with solar cells on the roof was investigated. The conclusion is that the property's energy use exceeds the average of Swedish premises' energy use. In connection with a possible renovation, the building has good opportunities for more efficient energy use. By carrying out all the measures that have been proposed, the heating demand can be reduced by 39% and the energy supplied can be reduced from 156.9 kWh / m2, Atemp, year to 103 kWh / m2, Atemp, year. Complementary installation of solar cells is a profitable alternative for reducing the building's extremely high electricity consumption.
333

Modelling bifacial photovoltaic systems : Evaluating the albedo impact on bifacial PV systems based on case studies in Denver, USA and Västerås, Sweden

Nygren, Anton, Sundström, Elin January 2021 (has links)
This study aims to develop a simulation and optimisation tool for bifacial photovoltaic (PV) modules based on the open-source code OptiCE and evaluate dynamic and static albedo impact on a bifacial PV system. Further, a review of the market price development of bifacial PVs' and an optimisation to maximise energy output was conducted. Two case studies with bifacial PV modules, a single-axis tracker in Denver, USA, and a vertical and a tilted system installed at a farm outside Västerås, Sweden, were analysed in this study. The results showed that an hourly dynamic albedo value could provide more accurate simulation results of the rear side irradiance for the bifacial single-axis tracker than a static albedo value. The developed model showed an R2 accuracy of 93% and 91% for the front and rear sides, respectively, when simulated with an hourly albedo value for the bifacial single-axis tracker system. The optimisation was based on weather data from 2020. The results showed that the tilted reference system could increase its energy output by 8.5% by adjusting its tilt from 30° to 54° and its azimuth angle from 0 to -39°. In contrast, the vertical system would increase its energy output by 2.1% by rotating the azimuth angle from -90° to -66°. Conclusions that could be drawn are that bifacial PV price has closed in on the high-performance monofacial PV price the last five years and may continue to decrease in the coming years. Further, it was concluded that detailed dynamic albedo values lead to more accurate simulations of the ground-reflected irradiance. The availability of measured albedo data at the location is essential when the ground-reflected irradiance stands for a significant share of the irradiance. It was determined that during 2020 the optimal configurations of a vertical and tilted bifacial PV system in Västerås would save 11 300 SEK by consuming self-produced electricity and earn 11 600 SEK from selling the surplus of electricity for the farm outside Västerås.
334

Study of Energy Neutrality in Kochi Metro Rail, India

Paul, Jeena January 2021 (has links)
Now a days, the society thinks about more sustainable and clean energy sources. Most of the countries in the world relay on non-renewable energy sources for the generation of electricity. This results in the scarcity of fossil fuels in future and also increases the production of carbon emissions. This thesis considers a metro system named Kochi Metro which is a rapid transit system serving in the city of Kochi in Kerala, India which uses renewable sources, mainly solar, for giving power to the Metro.In this thesis work, trying to analyze the measures adopted by Kochi Metro Rail project in potential reductions of energy consumption and energy generation both contributing to energy efficiency.With the help of Matlab, different levels of installed PV power are used to find out the possible self-usage, self-sufficiency, and energy neutrality of the system.
335

Solceller och batterilagring i HFABs klimatsmarta flerbostadshus / PV-cells and storage batteries in HFAB´s climate smart multifamily buildings

Karacadag, Lutfi, Persson, Carl Adam January 2021 (has links)
The degree project was carried out in collaboration with Halmstad Fastighet AB. Two separate buildings with different uses of energy have been analyzed. The focus was on evaluating near-zero energy houses with solar power plants and associated battery storage to investigate profitability and dimensioning to form the basis for future constructions. Both properties are near-zero energy houses but differ in the use of electrical energy. It is currently unclear how the change in the dimensioning of the solar power plant and the battery storage will affect the profitability of two properties with different uses of energy. The method was quantitative. Simulation models in the Polysun software were created with the properties' reference house. Based on the simulations, profitability calculations were made to describe the difference in profit when changing the dimensioning. The work concludes that the total profitability increases with the size of the solar power plant, regardless of energy use, and battery storage is not profitable without price changes. / Examensarbetet gjordes i samarbete med Halmstad Fastighet AB. Två olika fastigheter med olika elanvändning har analyserats, där fokuset låg på att utvärdera nära-nollenergihus med solkraftsanläggningar och tillhörande batterilager för att undersöka lönsamhet och dimensionering som ska ligga till grund för framtida byggnationer.  Båda fastigheterna är nära-nollenergihus men skiljer sig åt i användning av elenergi. Det är idag oklart hur förändringen av dimensioneringen av solkraftsanläggningen och batterilagret påverkar lönsamheten i två fastigheter med skilda användning av elenergi. Metoden är av kvantitativ karaktär. Simuleringsmodeller i programvaran Polysun skapades med två fastigheter och dess solkraftsanläggningar med tillhörande batterilager som referens.Utifrån simuleringarna gjordes lönsamhetsberäkningar för att beskriva skillnad i vinst vid förändring av dimensionering. Slutsatserna av arbetet är att den totala lönsamheten ökar ju större solkraftsanläggningen är oavsett elenergianvändning och batterilagret är idag inte lönsamt utan prisförändringar.
336

Optimal Pitch Distance and Tilt Angleof PV Power Plant for Different Climate

Alsulaiman, Mohamad, Mohammadi, Najmeh January 2020 (has links)
Finding the optimum inter-row spacing and installation tilt for tilted or ground mounted PV systems is a big issue in designing the large-scale PV systems. Increasing the array spacing leads to higher annual generated energy because of the reduced impact of row-shading, but on the other hand, it increases costs of land purchase/lease and wiring costs. Many compromises between performance and cost should be done to design an optimum large-scaled solar plant. One of the criteria in designing of solar power plants is reducing of LCOE, which reflects the cost of every unit of generated energy. Site locations have large impacts on the optimal design of pitch distance and title angles, but such impacts have not been studied extensively in the existing studies, so it is going to bridge this research gap in this thesis.   The main purpose of this research is to investigate the impact of climate conditions on the pitch distance and tilt angle for large-scale PV plant and finding the optimal pitch distance and tilt according to the least cost of production. The impact of climate and meteorological data on the self-shading loss and yield of energy are investigated through a simulation tool, which is PVsyst software here, in different tilt angles and distances between rows. The different climates can be considered by choosing site locations in different latitudes to cover all climate zones. Six cities in temperate climate, three cities in tropic climate and one city in polar climate have been selected. LCOE minimizing is a measure in finding the optimum tilt and pitch distance for a 1 MW solar system installed in different latitudes. In this study the type, size and cost of components have been assumed constant in different climate conditions. There is a wide range of variability in some economic indicators like interest rate and discount rate as well as the cost of land in different climates or even countries in the same climate; then to highlight the impacts of climate conditions on the optimal tilt and pitch distance, these parameters were assumed to be constant in this study.   The results show the optimal tilt of angles increases with getting far of equator in a range between 0° and 40° to capture more direct sunlight, and the optimal raw spacing grows in further locations to equator in a range between 4 m to 11 m to reduce self- shading loss. Moreover, the best module configuration for PV arrays (portrait or landscape) can be different in different climates.
337

Účinek interakce deficitní výživy a výskytu bakterióz na růst a vývoj rostlin rajčete jedlého (Solanum lycopersicum L.)

Školníková, Marie January 2017 (has links)
The aim of this diploma thesis is determination of the influence of deficient nutrition in combination of Pseudomonas syringae pv. tomato infection on tomato (Solanum lycopersicum L.) growth and development. In hydroponic cultivation experiment, tomato variety Darinka was cultivated in solutions without N, P, K, Ca, Mg and in variant with all nutrition (control variant). The dry matter of root and stem was weighed and root length, density and electrical capacitance were set. The content of nutrition in plants was also assessed. The level of infection was determined in 1st term, the highest level had plants with insufficient of Ca and P. High reduction of root and stem dry matter was found in Ca, N, P and Mg deficient plants. The low root electrical capacitance, length and density was determined in plants with Ca, N a P deficiency within infected group and in Ca and N deficient plants within noninfected group. Bacterial infection caused the reduction of all observing parameters in contrast to the plants from noninfected group. The antagonism and synergism between the elements were also showed.
338

Systems Modeling and Economic Analysis of Photovoltaic (PV) Powered Water Pumping Brackish Water Desalination for Agriculture

Jones, Michael A. 01 May 2015 (has links)
Global growing demand for agricultural production has put increased pressure on freshwater resources in various global locations. Many areas have saline groundwater resources which have not been utilized for agriculture due to the economics associated with water pumping and desalination. Limited availability to electricity and high operational costs of diesel generators are major obstacles to utilization of these resources. Reduced costs associated with large-scale renewable energy have renewed interest in understanding the potential impacts of developing distributed photovoltaic (PV) powered water pumping and desalination systems for agriculture. In order to determine the economic feasibility of solar-powered water pumping and desalination for agriculture, an engineering system model that performs hourly simulations of direct-coupled PV pumping and desalination systems by integrating environmental resource data and industrial component performance data was developed. Optimization algorithms were created to identify the best membrane type, control method and reverse osmosis system configuration for a given set of locational parameters. Economic analysis shows that PV-powered systems are more economical than diesel-powered systems for water pumping, with water desalination costs for PV- and diesel-powered systems being comparable. Grid-powered systems are able to pump and desalinate water for a lower cost than PV or diesel for all cases evaluated. A sensitivity analysis is performed to generalize results for different input parameters and illustrate the impact of input variables on water unit costs. Several case studies in the Jordan Valley were evaluated to illustrate the economic viability of solar-based systems with simulation results including a direct comparison to diesel- and grid-connected alternatives. Results indicate that under fair environmental conditions and irrigating greenhouse vegetables, the PV-, diesel-, and grid-powered systems produce favorable internal rates of return of 40%, 84%, and 248%, respectively. Under poor environmental conditions and less profitable crops the PV-, diesel-, and grid-powered systems all result in negative internal rates of return, illustrating the need for optimal location and crop selection for system implementation.
339

Optimization of the Photovoltaic Time-series Analysis Process Through Hybrid Distributed Computing

Hwang, Suk Hyun 01 June 2020 (has links)
No description available.
340

Maximizing the Value of Large-Scale Solar PV Parks through Battery Storage and Ancillary Services : An analysis using multiple-integer linear programming optimization

Ekström, Nora January 2023 (has links)
Renewable power production is becoming a necessity to improve society and overcome the challenges of climate change. In Sweden, large-scale solar PV power is growing year-on-year and today comprises 1 percent of electricity production. Solar power, however, is an intermittent form of electricity production which, whilst being renewable, contributes to increasing grid instability. For the grid to stay in balance, at grid frequency 50 Hz, electricity must be consumed at the time of production. If there is a surplus of production or a sudden decrease in consumption, the frequency will deviate from the nominal value. When introducing larger quantities of intermittent power production, the power system inertia decreases, and the frequency becomes prone to deviate. To combat this, the Swedish TSO Svenska Kraftnät procures ancillary services which aid the grid when needed. For solar PV power to be able to contribute to these marketplaces, a battery storage solution system (BESS) is utilized. This thesis aimed to investigate the economic feasibility of co-locating a solar photovoltaic (PV) park with a battery energy storage system (BESS) and to determine the optimal size of the BESS. The study utilized a linear optimization model to simulate the operation of a 14 MW solar PV park with different sizes of BESS ranging from 1 MWh to 14 MWh. The analysis considered the revenue generated by providing different services to the electricity grid, such as energy arbitrage and frequency regulation. The results indicate that co-locating a solar PV park with a BESS increases revenue, and the optimal BESS size for a 14 MW solar PV park is between 1 and 8 MWh. Above this range, the revenue recedes due to the limitations of the grid connection, which restricts the BESS from participating in the ancillary service markets. The analysis considers the running costs associated with power discharge to the grid and initial BESS investment. The study did not account for ancillary market bids that are not accepted, which could have a significant impact on the revenue generated. The ongoing trend of lowering battery prices could further boost the economic assessment and increase interest in all battery sizes, resulting in larger battery system installations in general.

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