Functioning Fuzzy Logic in Optimizing the Solar Systems Work

Fuzzy logic has been used in many fields, either to control a specific movement, improve the productivity of a machine, or monitor the work of an electrical or mechanical system or the like. In this chapter, we will discuss what are the basic factors that must be taken to use the fuzzy logic in the aforementioned matters in general, and then focus on its employment in the field of renewable energy. Three main axes for renewable energy are solar panels, a wind turbine and finally, solar collectors. The key to working and the basis of the static system is the mechanism for selecting the inputs that directly affect the output in addition to the methods and activation functions of the fuzzy logic.

Forecasting of Wind and Solar Farm Output in the Australian National Electricity Market: A Review

Accurately forecasting the output of grid connected wind and solar systems is critical to increasing the overall penetration of renewables on the electrical network. This is especially the case in Australia, where there has been a massive increase in solar and wind farms in the last 15 years, as well as in roof top solar, both domestic and commercial. For example, in 2020, 27% of the electricity in Australia was from renewable sources, and in South Australia almost 60% was from wind and solar. In the literature, there has been extensive research reported on solar and wind resource, entailing both point and interval forecasts, but there has been much less focus on the forecasting of output from wind and solar systems. In this review, we canvass both what has been reported and also what gaps remain. In the case of the latter topic, there are numerous aspects that are not well dealt with in the literature. We have added discussion on the value of forecasts, rather than just focusing on forecast skill. Further, we present a section on how to deal with conditionally changing variance, a topic that has little focus in the literature. One other topic may be particularly important in Australia at the moment, but may become more widespread. This is how to deal with the concept of a clear sky output from a solar farm when the field is oversized compared to the inverter capacity, resulting in a plateau for the output.

Transition towards a full self-sufficiency through PV systems integration for sub-Saharan Africa: a technical approach for a smart blockchain-based mini-grid

Access to affordable, reliable and clean energy is an important sustainability goal of the United Nations. In areas where the public electricity grid is unreliable or unavailable, photovoltaic systems can be a solution. However, they are cost-intensive, mainly because of the energy storage systems. Mini-grids can be an answer for reducing upfront investment and overall system lifetime costs while increasing electricity availability. The mini-grid technology is mature, nevertheless, there are downsides when it comes to integrating existing solar systems of different manufacturers. The system topology is usually predefined and a central instance controls the mini-grid. Thus, the integration of existing power systems is difficult due to the communication constraints of these systems with the mini-grid controller. Including existing power systems into a decentralized mini-grid, can highly increase cost-efficiency. In a decentralized approach payments for the consumed energy between mini-grid actors are required. Accounting is, however, a complex administrative procedure, if the respective power systems are owned by different individuals and organizations. A transparent blockchain-based temper-proof approach can be a solution to automate metering and billing, allowing automatic payments between independent subsystem owners using smart contracts. In order to further optimize the smart mini-grid, an artificial intelligence learning algorithm for a dynamic electricity price needs to be developed. This smart and decentralized approach for building Mini-Grids is a novelty bringing solar systems one step closer to self-sufficiency. This paper describes how a smart mini-grid solution can be implemented using the Don Bosco Solar & Renewable Energy Center campus mini-grid in Tema, Ghana as a case study.

Mass flow rate optimization in solar heating systems based on a flat-plate solar collector: A case study

Little works considered the optimization of working fluids in solar systems. Engineers, designers and scientists are interested with the optimization problems, furthermore it is very important specially, for solar systems to improve the energetic behavior and increase their efficiencies as a conversion system of solar irradiance to a useful thermal power. According to the available literature, the criteria of optimization mainly relates to energetic and economic analysis (one of them or both). The analysis was based upon the maximum useful energy obtained from solar collector. Accordingly, the optimum mass flow rate was found aspires to infinity. The second analysis is based upon minimum cost of the unit of useful energy [$/W]. The optimum mass flow rate of solar air-heating flat-plate collector for the considered domestic solar heating system has been found 29 kg/h per square meters of solar collectors. This paper deals with a third criteria that is, the amount of the additional energy required to achieve the required task from the solar system by means of auxiliary heating system. In where both the outlet temperature and mass flow rate play crucial role in the heat exchange between the fluid in the collector loop and the fluid in the load loop.

Theories on the Formation and Evolution of ~2D Planar Celestial Kinematics

The existence of essentially 2-dimensional planar solar systems and galaxies would seem to be a contradiction to the 2nd Law of Thermodynamics relating to the tendency of natural processes toward spatial homogeneity of matter and energy. During the formation process of celestial systems, an equal dispersion of matter throughout 3-dimensional space would have been a more logical result to satisfy entropy/disorder increasing at all times. Conventional belief is that the ~2D planar geometry of galaxies and solar systems is largely due to rotational kinetic forces and matter collapsing due to its own gravity; this project seeks to expand and enhance the potential forces to explain ~2D planar celestial kinematics. Computational mathematics utilizing programming in C# will analyze various potential forces and relative magnitudes to determine proposed force-balances during these formation processes. A better understanding of the formation process (and the forces that govern them) of galaxies and solar systems can help explain their evolutions to steady state; for this, the derived mathematical models will be computed and translated to visual models in 4-D space-time over various time frames.

Study and Feasibility of a Flat Collector Cooker using Vegetal Heat Transfer Fluid

Solar cookers currently produced are solar systems that use parabolic heat transfer to concentrate sun rays on a cooker. The new trend is focus on the cooker that uses a flat collector operating as a thermosiphon where the heat transfer fluid (oil) flows by natural convection. They are developed to address household needs at a lower cost, making them popular both in terms of research and use. Some of vegetable oils were previously investigated and which could be used as heat transfer fluids in such systems. A digital study using vegetable oil called "Kibi oil", an artisanal oil produced in Côte d’Ivoire, as a coolant, was conducted under poor weather conditions to calculate temperatures that could be reached in these cases. In the Sahelian zone, conditions are much better than these, and we can expect fairly excellent results. This study focused on temperature variation at different areas (1, 2, 3 and 4 specified in the diagram) of the cooker, on the mass flow of the fluid throughout the study day and to some quantities which enable to follow the performance of the solar collector of the stove. Sunlight measurements used are those of the city of Abidjan made in September, a very cloudy day with poor weather conditions. Temperature T3, very close to that of the hot plate, was around 110 °C between 10:30 am and 12:30 pm, which enables to cook certain dishes during this period. It should be noticed that at the exit of the flat panel collector, over the same period, the temperature is around 120 ° C. At that same time, the collector efficiency varies around 30%.

Simulation of fault detection in photovoltaic arrays

In solar systems, faults in the module and inverter occur in proportion to increased operating time. The identification of fault types and their effects is important information not only for manufacturers but also for investors, solar operators and researchers. Monitoring and diagnosing the condition of photovoltaic (PV) systems is becoming essential to maximize electric power generation, increase the reliability and lifetime of PV power plants. Any faults in the PV modules cause negative economic and safety impacts, reducing the performance of the system and making unwanted electric connections that can be dangerous for the user. In this paper have been classified all possible faults that happen in the PV system, and is presented to detect common PV array faults, such as open-circuit fault, line-to-line fault, ground fault, shading condition, degradation fault and bypass diode fault. In this studies examines the equivalent circuits of PV arrays with different topological configurations and fault conditions to evaluate the effects of these faults on the performance of a solar system, taking into account the influence of temperature and solar radiation. This work presents the validation of a simulated solar network by measuring the output curves of a low-power photovoltaic array system under real outdoor conditions. This method can be useful in future solar systems.

Solar Energy in the Nordic Built Environment: Challenges, Opportunities and Barriers

Within the framework Solar Heating and Cooling Programme of the International Energy Agency Task 51 “Solar Energy in Urban Planning”, case studies from Norway, Sweden, and Denmark were collected and analyzed through a comparative approach. The cases were first classified based on their urban characterization (existing and new urban areas) and then compared within the same country or in a cross-country perspective according to three areas of interest (i.e., Scale and planning process, Legislation and planning process, Targets and goals). The comparisons follow a common template of five sections describing the role of the involved stakeholders and highlighting challenges, barriers, and opportunities for the deployment of active solar systems and passive solar strategies. Both technical and non-technical aspects are considered. Among the technical aspects, the focus is on the adoption of solar energy strategies (e.g., solar accessibility, daylighting), the estimation of solar potential and energy generation. Regarding the non-technical aspects, the focus is on identifying barriers and challenges for the adoption of solar systems in relation to national and local legislation. The findings show that municipalities can have a crucial role in facilitating the adoption of solar energy solutions in cities by embracing ambitious visions and storytelling, as well as being directly financially involved as owners or subsidizing bodies. The findings also demonstrate the value of the use of indicators to evaluate the performance of masterplans, the combination of analogue and digital tools in the design process, and the performance of solar simulations from early stages to foster awareness among the involved stakeholders. Despite these positives, the Scandinavian legislation on solar energy utilization in the urban context still displays fragilities, making the creation of guidelines a pressing need.

Enhancing the aesthetic aspect of the solar systems used as facades for building by designing multi-layer optical coatings

The design of zero-energy buildings can be depending on the effective integration of solar energy systems with building envelopes, where these systems save heat and electricity as well as enhance the aesthetic aspect of the facades. In this paper, the aspects related to the effective integration of buildings with solar energy systems (solar cells and collectors) will be discussed, as well as enhancing the aesthetic aspect of the facades, and since solar energy systems are visible to everyone, their design must adapt to the building structure and the surrounding environment. Solar energy system designers, architects, physicists and other contributors to building energy envelopes must consider the comprehensive concept of it, where buildings are part of the human and social environment and in close relationship with the natural environment, through the use of thin films technology through the design of multi-layers colored optical coatings covering solar panels for building facades. Accordingly, the energy sector should be seen as an area of aesthetic creativity. Two dielectric materials were used, the first is ThF4 with a high refractive index (1.5143) and the second is LiF with a low refractive index (1.393) and for several odd layers, starting from 3 layers and up to 21 layers and for a thicknesses of a quarter wavelength. The design Air/L/H/Glass was applied by the Mat Lab program for the seven colors of the spectrum, So, the aim of this research is determined in designing colored optical coatings for solar systems that enhance the aesthetic aspect of building facades, as well as generating thermal and electrical energy needed to operate the buildings and to find out which color has the best visible reflectivity and solar transmittance better than the rest of the spectrum, all the results exhibit that yellow color has the higher visible reflectivity and higher merit factor, so it is consider the most efficient color for coloring the solar systems than the rest of colors spectrum.