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This paper presents an approach of investment risk analysis for small hydro power plants (SHPPs) considering energy trade in the short-term market in Brazil. The Monte Carlo Method, associated with a Cholesky decomposition, is applied to stochastic models to generate synthetic time series for water inflow and short-term electricity price. An economic approach is presented taking into account taxation...
This paper is an experimental and theoretical method developed in laboratory bench that uses a geoelectrical method, the Wenner method, to correlate the changes in electrical resistance of soil produced by chemical fertilization. The developed methodology allowed to know the dynamic behavior that some common fertilizer causes on the electrical resistance measurements of the soil under study. The applied...
This paper proposes a methodology based on system connections to calculate its complexity. There are proposed two study cases: the dining Chinese philosophers problem and the distribution center. Both studies are modeled using the theory of discrete event systems and simulated in different contexts in order to measure their complexities. The obtained results present i) the static complexity as a limiting...
Solar water heating in homes of low-income families as Energy Efficiency Action enables energetic benefits from points of view of the consumer and the Brazilian electrical system, thereby reducing environmental impacts associated with generation, transmission and distribution of electricity. The purpose of the present study is to evaluate these gains through measurement and verification methodology...
This paper deals with the calculation of ground resistance, surface voltage, touch voltage and step voltage, to mesh with horizontal wires arranged in different angles. The mathematical modeling is based on the method proposed by Heppe, which allows obtaining the grounding parameters for soil stratified in two layers. Moreover, the results obtained by the Variable Currents Method (VCM) have been compared...
In modern agriculture, the knowledge of the soil properties is a key factor for profitability in the production. However, data acquisition and processing are limiting factors for its use, since they require specialized labor. The automatic instrument that provides information about soil penetration resistance, which is described here replaces the traditional system and automatically obtain reliable...
Solar water heating in homes of low-income families as Energy Efficiency Action enables energetic benefits from points of view of the consumer and the Brazilian electrical system, thereby reducing environmental impacts associated with generation, transmission and distribution of electricity. The purpose of the present study is to evaluate these gains through measurement and verification methodology...
This paper presents the study of the relationship between soil apparent electrical resistivity ρa and i) the moisture content, ii) clay content and iii) soil compaction, for use of the ρa as a mapping tool of spatial soil variability. It was held measures of ρa in different soil types, varying moisture content gradually while maintaining a constant compaction, and then varying the compaction and relating...
This work proposes itself through mathematical modeling, simulating the electrical interactions between two electrical generators, an induction generator and a synchronous generator connected to a common bus in steady state, subject to non-linear load. By comparing the modeling of the two machines, we can see that the induction generator will present best way for the harmonic currents flowing in common...
The importance of precision agriculture techniques increasing, but data interpretation, instrument cost and qualified personnel for application limit its measurement on croplands. The development and validation of an intelligent apparatus that provides information about soil compaction using Cone Index, described here, replaces the traditional system and obtain reliable data with higher resolution...
The purpose of this paper is to model the operation of a thermoelectric generator (TEG), in order to simulate the process of power generation and control a converter connected between the TEG and the load. The Perturb and Observe (P&O) technique is validated by screening and operation of Maximum Power Point Tracking (MPPT) in generation systems based on TEG. The operation at maximum power point...
With following world demand for electricity and increasing scarcity of natural energy resources, it is imperative to search for alternative methods for electricity production or increasing the efficiency of existing processes. The use of Seebeck modules have been shown the green output of power cogeneration using waste heat energy. Furthermore, the overall conversion efficiency of thermal energy into...
This paper presents initial studies on thermal heat dissipation in a high-power 5W LED (Light Emitting Diode) luminaire. Two types of heat sinks are proposed, and three thermal simulations are presented through an analysis by finite element methods (FEM). The first simulation considers a luminaire consisting of a confinement, a LED, and a star shaped heat sink base attached. The second simulation...
This research work presents a technical and economical analysis of a grid connected photovoltaic system to be installed on the rooftop of an industry in the state of Goias, Brazil. Calculations were made to obtain the system's potential for photovoltaic power generation, as well as the economic feasibility indicators based on the project's lifetime, in order to inform investment decisions. Research...
Generating machines of electricity, using combustion engines and generate a great amount of residual thermal energy from the exhaust gases. This residual thermal energy can be converted into usable electricity using thermoelectric generator (TEG), which are manufactured cells with semiconductor materials employing the Seebeck effect. When recovering the waste heat in the exhaust ducts using TEG, increases...
This research work presents a methodology for investment risk analysis in a photovoltaic power plant. Stochastic modeling are developed for the variables solar irradiance, photovoltaic panel temperature and price of electricity in the Brazilian spot market. A case study is presented to validate the applicability of the methodology. The method is developed considering various characteristics of the...
This research work presents a methodology for investment risk analysis for eolic power plants. A stochastic modelling was developed for the variables Wind Speed and Price Settlement of Differences (PSD), with the aim of analyzing cash flow during a power plant's lifespan. Simulated scenarios have been created with the Monte Carlo Method to analyze the random variables involved in the process. The...
This paper reports on a PID controller for speed control of a DC motor. The controller parameters were obtained through optimization methods employing heuristic and deterministic strategies. This methods were applied on a simulation model in order to verify which one provides better control results.
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