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The objective of this work is to reduce energy costs for a consumer with multiple available energy resources and with an energy storage system. To achieve this, it is developed a methodology with a multi-criterion analysis that considers the demand side, the real-time prices, and the availability of the energy resources. In other words, the developed methodology manages the multi-source system, allowing savings for a consumer. In addition to the presentation of the methodology, it is made an application in a case study. It is considered and modeled a real consumer that has three different energy resources, including energy storage by battery. The situation comprehends solar generation, diesel generator and the electrical power grid. There are simulations and the results comprehend the savings for this consumer, considering the methodology application. The main result is a reduction in energy costs by 33.3%, considering the situation without this methodology. For the purpose of indicating the use of the storage system, it is presented the battery’s state of charge along the simulation. Also, there is a verification of the methodology’s robustness, through another simulation, using theoretical data for the consumer. In this case, the consumer has energy storage system, solar generation, biogas generator and the electrical power grid. In this situation, there is a reduction in energy costs by 30.2%, considering the situation without this methodology. In conclusion, the results show that the developed methodology is effective. In the two case studies presented there are significant savings for the consumer.

This work aims at developing and validating mathematical models and empirically evaluating a water‐film cooling system for commercial photovoltaic modules. Methodologically, thermal, electrical and climatological data measured in a specific purpose on‐grid outdoor test unit were used. In this work they are used to study the improvement in the performance of photovoltaic energy production due to temperature reduction. The first‐order state‐space linear parametric model presents the best performance to predict the temperature of the uncooled photovoltaic modules, with normalised mean square error (NRMSE) of 86.75%. In contrast, the non‐linear model performance of cooled photovoltaic modules is lower, with NRMSE of 44.5%; however, the results show that the performance of the complete thermoelectric model is satisfactory, with NRMSE of 76.38%. On the other hand, empirical tests showed that the cooling system reduces temperature in 15–19%, on average, and to a maximum of 35%. In terms of power, there are average gains of 5–9%, and maximum gains of 12%. Regarding gross generation, there are average gains of 2.3–6%, and maximum gains of 12%. It was concluded that it is possible to mathematically model and predict this generation using non‐linear models with a 0.2% error between modelled and measured generation.

The objective of this work is to identify the premises and strategies for the design of a zero-energy solar house and propose the systematization of its process. The focus of the application is on the single-family residential typology. The method consists of analyzing the whole process from the initial phase of the architecture project to the use of automation systems, aiming at the best use of solar energy in terms of sustainable development and high energy efficiency. Each phase of the process has significant importance in the performance of the residential unit, however, the influence that one phase has over another plays a fundamental role in the final result. The process of systematization encompasses all these phases, starting from the demands for energy in a solar house and introducing strategies to meet these demands. The prototype of the zero-energy solar house is used as an example of the application of this process for the development of a parametric solar house. The results show a strong positive correlation of linear dependence between the assumptions and strategies used in the architecture of the house and the solar system, allowing a conclusion of the dependence relation on sustainability, thermal comfort, visual and energy efficiency.

This paper constructs probability density distributions of direct normal, diffuse horizontal, and global horizontal irradiance for 1-min clearness indexes kb, kd, and kt, respectively. Previous studies on the clearness index, conditioned to the optical air mass, are analyzed and distributions of these three indexes, using data from two solarimetric stations in Brazil, are presented. The pattern found in probability density distributions, in general, matches the patterns found in the literature. The 50th percentile (P50) of kb values from Sao Paulo city (a location with high levels of pollution) is 0.22, and from the countryside region of the state of Sao Paulo (a location with expected low levels of pollution), it is 0.55. Regarding kt values, P50 is 0.57 and 0.72 for these two regions, respectively. We conclude that different atmospheric conditions result in a different dependence relation between probability density distribution and air mass increases. These conditions include not only cloud formation, but also pollution levels and the influence of relative humidity. These specific results endorse the need for local radiation measurements to the characterization of few-minute average of transmittance indexes.

The objective of this study is to evaluate the potential for electricity generation in the State of Sao Paulo (SP) from the sewage treatment. A sewage treatment plant (STP) with domain in the production of biogas from wastewater treatment plant (WWTP) is the basis for this case study. The basic premise is that the very generation of electricity in STPs is advantageous for companies in the sanitation sector in Brazil, resulting in cost reductions of the treatment process. Gains at the end of the process are found in two levels, namely: (i) economic, by generating 165% of electricity from biogas burning in relation to the expend; (ii) energy, by adding a new sustainable and storable energy source equivalent to 4% of natural gas offered in the State of SP and 0,5% of electricity produced from biogas burning in relation to electricity consumption. In conclusion, the potential of electricity production linked to the biogas at STPs is capable of supply its domestic demand and export the surplus to other segments of the state and national economy.

This paper presents a method of characterizing Load Distribution Networks for peak load pricing, using load profiles sampling from consumer units, commercial distribution database, and climate variables. It is considered rate subgroup, consumer class, and temperature as exogenous variables. The temperature data considered in the model are directly related to load destined for cooling and heating. Modeling is supported by Artificial Neural Networks methodology with Multi-Layer Perceptron architecture and Back-Propagation training algorithm. In a real case study, load profiles in the Brazilian electrical system, from September 2013 to August 2014, are compared with clustering models traditionally used in load profile characterization to peak-load pricing. The model provides a forecast error equivalent to 5.46% in the distribution sector, lower than the forecast error of 23.04% for the clustering model and load typologies.

O trabalho utiliza modelo inédito de cálculo de Tarifas de Uso dos Sistemas de Distribuição – TUSD na forma microgranular, calculadas por unidade consumidora e por hora, seguindo o princípio tarifário da causalidade de custos. O modelo é aplicado à concessionária de distribuição real utilizando dados dos processos de revisão tarifária periódica, constituindo o caso base de estudo. Das curvas tarifárias é possível calcular um Benefício Econômico – BE (R$/MWh) para cada unidade consumidora, decorrente da instalação de Sistemas de Armazenamento de Energia – SAE em função do tempo de descarga no período de ponta. Ao se aplicar uma única tarifa horária para todos consumidores (modelo vigente) obtém-se um BE de 469,93 R$/MWh, enquanto o percentil 95% dos BE de cada uma das unidades consumidoras (modelo proposto) resulta em 1.375,19 R$/MWh para 3 horas de descarga. Adicionalmente são apresentadas as distribuições de probabilidade demonstrando a influência da aplicação de uma tarifa dinâmica em detrimento de uma tarifa horária isonômica para área de concessão, o que poderia aumentar significativamente a viabilidade de investimentos em SAE pela concessionária ou consumidores. O modelo se mostrou robusto e demonstra a viabilidade de adotar modelos holísticos na definição das tarifas, que observe a integralidade os efeitos da inserção dos Recursos Energéticos Distribuídos, em detrimento do reducionismo adotado atualmente no ambiente regulatório.

The article presents a probabilistic analysis of the dispatch of a multi-source system. It was used the Monte Carlo method to evaluate the voltage and current profiles in the load and the battery, as well as the power factor and transformer loading. Besides, an economic analysis was carried out for each scenario generated, finding the optimal operation cost of the system. The optimal scenario was that which resulted in a decrease of 23.89% in cost operations when compared to the one without battery and generator.

This work presents an overview of the parameters regarding modern energy consumers’ representation. As new energy generation technologies are implemented, attending an increasing demand and sustainability goals, the role of modern consumers changes in comparison to previous activities. The new framework of the sector implies broader changes than operational and technical ones, enabling a more active market, improved usage of resources, and encouraging participation. To support the entry of modern consumers, new engaging initiatives must be encouraged. Groups are one way to ensure that consumers may engage themselves in the energy sector, enabling communication enhancement and demands attending. There are several consumer groups currently with different work methods and engaging initiatives. This work concerns to describing their members, their approach regarding decision-makers, and how the communication is enhanced. As groups, the work encompasses groups in the United States, Australia, European Union, and Brazil. As a result, the existing groups are described according to the communication, participation, and member selection parameters.

Renewable energy was responsible for more than a half in world capacity additions growth in 2017 and its share in total capacity increase will grow 46% until 2023, supporting an energy transition scenario [1],[2]. The employment of a technology that ensures a secure supply and expands renewables integration is a turning point in such a scenario. Energy Storage Systems (ESS), mainly batteries, may be the technology fundamental to bolster the growth of the renewables [3],[4], due to its services providing that may lead the deployment of the renewable, simultaneously ensuring the balance of the grid [3],[5]. Despite the strong confidence in the new role presented by ESS, there are still some concerns regarding business and legal barriers, and grid stability [4] [5]. To overcome uncertainties and foster storage implementation, it is fundamental to map risks and uncertainties and identify further benefits as parameters for an ESS implementation project. This work developed a framework to guide an ESS implementation into a timeline, separating the required actions into short, medium and long-term. The required actions consider opportunities and risks regarding market orientation, society and populational changes, available technologies, political targets, and climatic agreements. The methodology labels these terms into barriers and opportunities, establishing working fronts and actions. As a result, it is expected a framework for an ESS insertion in Brazil. [1] I. E. Agency, “Renewables 2018 market analysis and forecast from 2018 to 2023,” 2018. [2] BloombergNEF, “Batteries boom enables world to get half of electricity from wind and solar by 2050,” 2018. [3] Eurobat, “Battery Energy Storage in the EU” EUROBAT, 2016. [4] I. Usera, P. Rodilla, S. Burger, I. Herrero, and C. Batlle, “The regulatory debate about energy storage systems: State of the art and open issues,” IEEE Power and Energy Magazine, vol. 15, no. 5, pp. 42–50, 2017. [5] A. Gallo, J. Simoes-Moreira, H. Costa, M. Santos, and E. M. dos Santos, “Energy storage in the energy transition context: A technology review,” Renewable and sustainable energy reviews, vol. 65, pp. 800–822, 2016.

The objective of thiswork is to analyze, through environmental vulnerability (EV), disturbances in the environment caused by anthropic activities for the production of energy resources, focusing on the power generation sector. Methodologically, hydrocarbons (oil and gas) and solar are considered through a qualitative and quantitative analysis of environmental impacts, including the research inside Environmental Impact Studies and procedures like EIA/RIMA (institutional Environmental Impact Reports in Brazil). This study focuses on operation and demobilization of offshore drilling activity, and installation and operation of the Santos Basin pre-salt oil and gas production and disposal activity Stages 1, 2 and 3. The criteria addressed in the EIA/RIMAs are used, focusing on thosethat correlate with EV and the production of electricity. Impacts for long-term, permanent, partially reversible or irreversible disturbances are filtered, totaling 53 impacts (31 effective/21 potential). We concluded that the criteria and methodologies of EIAs vary between stages. At times, the variation is so drastic that the same impact can have a completely different rating from one stage to another, despite referring to the same area. This condition makes it impossible to define a single vulnerabilityindex for the pre-salt venture. For a final analysis, we propose a cleaner energy production through distributed photovoltaic systems as a more adequate alternative for Sao Paulo’s energy supply in terms of its impact on EV.

The objective of this research was to present the concepts to determine the reliability of the multisource system in the commercial sector of a small electrical grid denominated Pilot Unit. Due to the evaluation and estimate of the reliability of Li-ion batteries in the Microgrid, the reliability of the multisource system was calculated. The calculation of the reliability of the Microgrid used the Weibull statistical model. The results had shown a direct relationship between the reliability of the multisource system and the reliability of the Microgrid elements. Therefore, the challenges and difficulties in the implantation of the reliability are susceptible to the environment where the project is found, because it is noted that to obtain reliability results, it is essential that there is a trustworthy historical database to calculate the reliability of the pilot unit, needing, this way, to refine the failure rates of the batteries as much as GMG (Diesel Generator).

The goal of this study is to develop units of a photovoltaic (PV) cooling system and evaluate its performance, aiming at commercial electricity production, once the increase in electricity output is obtained by cooling down the temperature of the PV module. The methodology covers the description of production procedures, control and verification of three different models of the cooling system, of which two are sheet-and-tube types, with different diameters of coil curvature (85 and 140 mm), and one is a multi-channel type model. Results show that the production of the two sheet-and-tube models presented no issues during their construction and operating phases, while the multiple-channel model presented some complications at the construction phase (e.g. the thickness of the sheets hampered the welding process, leading to leakages during the tightness tests). The empirical control tests showed that the temperature of the PV module with a cooling system applied remains lower than the nominal operating cell temperature, whereas the PV modules without a cooling system presented temperatures higher than 68.1°C. Thus, the authors conclude that the most appropriate model for large-scale production applied at PV systems is the coil one, with 85 mm of the diameter of coil curvature.

The objective of this work is to analyze the intrinsic aspects for policy dimension inside the energy planning and energy long term sustainability. In that sense, the methodology intends to take the Brazilian example as a case study and offer a somewhat unorthodox perspective on the subject of State energy planning. This matter is, beyond a purely technical question or a problem for the field of exact sciences, a point of primary interest to the field of social and human sciences. More the backbone methodology in this research is the Integrated Energy-Resources Planning (IRP), chosen for its ability to integrate both the supply and demand perspectives in the discussions about energy planning [1] [2]. A historical perspective is a guideline to approach issue: starting at the early Twentieth century, this study covers the major landmarks of the country energy concern to the present day; particularly noteworthy are the implications of the realpolitik—that is, the elements in politics that are developed within the institutional frameworks, such as governmental plans and decisions. As a result, it presents a complex picture, which we try to understand from the perspective of supply and demand integration. The originality of the study lies in the refusal to accept fallacious technical statements, as we consider the issue primarily a human and social problem, but considering the validity of technical statements that are correct.

The objective of this work is to apply the methodology of PIR (Integrated Energy-Resources Planning) within the corporate environment. It was chosen a pulp and paper industry because it is one of the largest energy consumers industry. In addition to the traditional resources, it was included a new technology, biomass gasification. Available gasification technologies were described. Within these technologies, there is an application which seeks to replace the current technologies of recovery boiler, black liquor gasification (LARSON, 2003). In this paper the concepts of PIR in the corporate environment will be applied – in a pulp and paper industry on the optics of Energy Resources Supply-Side (RELOs). The result of IRP was that the resources chosen to meet the demand in this industry in study were: Hydroelectricity, Recovery Boiler, Natural Gas Boiler / Oil, Biomass Boiler. It was found that almost all resources are used in the first years of operation and that during the study period, it was not necessary to include new resources for the demand increase was met with the already allocated resources.

The objective of this study is to validate a zero-energy solar house (ZESH) as a sustainable development tool, based in accounting greenhouse gases (GHG) emissions mitigation. The method considers a multicriterial assessment for electricity conservation, power generation and GHG reduction. The potential and limitations of photovoltaic systems (PVSs) and the electricity consumption of the residential sector are studied. The guidelines and strategies of a ZESH are defined, focusing on the use of the sun in architecture, solar heating and PVSs through a qualitative analysis. These studies are carried out through a zero-energy house model (considering the annual consumption of a residence connected to the grid) that incorporates the guidelines and strategies of a solar house. The bioclimatic strategies and solar systems are analysed considering its application in Sao Paulo. The evaluation of passive strategies for thermal conditioning demonstrates a potential to increase by 70% the hours of comfort in the year. Using more efficient technologies for artificial lighting shows an energy conservation potential of around 12.5%, within the defined parameters and considering the average residential consumption. The use of a solar system to heat water has the potential to save up to 16.3% of energy compared to a business-as-usual scenario (traditional house). The electricity generation by PVSs combined with the adoption of energy efficiency measures demonstrates a potential to achieve, at least, zero net annual energy balance relative to the business-as-usual residential consumption of the grid. Thus, a potential to avoid up to 1.66 t CO2 per year for each housing unit is estimated.

The growing application of renewable energy with accessible price and technology, together with Distributed Generation techniques came to bring a paradigm shift in the existing relations of distribution network in the past years. This work assesses the application of Distributed Generation by the consumer as a microgenerator – a “pro-sumer” - by usage of Photovoltaic generation. The presented methodology considers the financial and technical effects in the relations between the utility and the prosumer. The results shows that, even with the residential consumer providing the project and the installation of the PV generation, it is in the distribution framework that this relation is technical and commercially affected, as both the utility and residential microgenerators face the infeasibility of the project. The methodology is validated by an application showing that further regulating and market efforts are required in order to effectively disseminate cogeneration for residential consumers and explore their solar potential.

The objective of this work is to analyze and evaluate the impact of cooling systems on photovoltaic modules (for electricity generation), applied at a pilot Testing Facility. The results obtained during this step are used as input in order to determine the best model to be applied at a real-scale Photovoltaic Power Plant (PVPP). This methodology is based on the monitoring and supervision of the operating temperature of commercial photovoltaic modules (PV), both with and without cooling systems, as well as on the study of the water supply design of the cooling system applied on a micro photovoltaic power plant which is connected to the commercial network. Through the analysis of the data, we observed that photovoltaic modules with cooling systems always operate at lower temperatures than the ones without cooling systems. During the testing period, the operating temperatures of the photovoltaic modules without cooling systems were above 60oC (with a maximum temperature equaling 68.06oC), whereas the maximum temperatures registered on the sensors of the model “A” were 43.55oC and 44.75oC, and the ones registered on the sensors of the model “B” were 46.76 and 48.33oC. Therefore, we conclude that the photovoltaic module with the cooling system model “A” is the most suitable for large-scale application, since it was the only model to present temperatures lower than the nominal operating condition temperature (NOCT) of the cell (47oC ± 2oC).

This paper aims to assess the Initial Investment Valuation Methodology of the local regulator, facing the results of auctions, due to the high occurrence of low clearing prices observed from 2003 to 2008 and the high percentage of auctions without any bidder recently. The regulator investment forecasted defines the maximum value of Yearly Allowed Revenue and the bidder that offers the lowest YAR value wins the auction. The first type of analysis considers project cost, location, execution deadline, transmission line extension and type of all actions from 1999 to 2015, totalling about 3.361 billion USD. It was not found any correlation of those variables and the result of the actions. The second analysis compared the equipment and the additional costs breakdown of the regulator investment forecast with the real investment in projects from 2009 to 2013 and it rarely surpasses 5%. Suggestions are proposed based on the analysis.

The aim of this work is design the multi-objective selection of Energy Resources – Supply and Demand Sides – considering the lowest full costs Energy Resource. It is a step of integration of the resources within the IERP (Integrated Energy Resource Planning). This involves each Energy Resource being characterized individually by approximately 50 attributes and sub-attributes, which are contained in four Dimensions: Technical-economic, Environmental, Social and Political. These dimensions can be considered the Four Main Dimensions of human and socioeconomic development. From a methodological approach, a holistic analysis was performed, where the decision makers and the actors enrolled are part of the choice of Energy Resources through the attributes that characterize them. Also, there is a deterministic analysis, where the complete characterization of the Energy Resources is done considering the local data. For this purpose, each Energy Resources also has been characterized on the complete cost basis, by means of Full Cost Assessment. Last, the Analytic Hierarchical Process (AHP) was applied in order to accomplish the selection itself. The main result is a multi-criterion ranking of energy-resources, based on all above mentioned attributes. The resources next to the demand side appear as lower full costs one. Considering these results it can be concluded that a selection based on the model enables the reduction of uncertainties and risks in the long term planning. Furthermore, this resulting list feeds the integration of resources in the process of implementation of the IERP.

This paper aims to highlight and enhance the tool called Computation and Valuation of Full Potentials (CVFP) for use in an electrical multi-sources microgrid (diesel generator, PV, grid connection and batteries energy storage system - BESS) to be installed in a medium voltage consumer unit. To this end, social, techno-economic, environmental and politico-regulatory information must be studied and applied for each of the elements in a pilot unit test. Therefore, this paper shows the definition of the qualifying elements (known as attributes and sub-attributes) and which make up each of the four mentioned macros parameters, called dimensions. The baseline of attributes and sub-attributes is sustainability, consequently the same elements defined for the Integrated Resources Planning of Energy (IRP) were used. Likewise, this paper shows what these parameters are and how they can be used to qualify the micro-grid energy sources.The qualification of energy sources against these parameters will be used later to make a comparison between systems with and without electricity storage, considering the frequency of use of each equipment established in the project. To conclude, it was observed that the qualification parameters of IRP can be adapted for use in different types of systems, as in the case of this multi-source system. It is due to the flexibility of CVFP tool whose was created with intended to be applied to any kind of energy system.

The objective of this work is evaluating the long-term hybrid power supply from wind and solar energy-resources determining the optimized ratio concerning installed capacities to attempt the power demand of a region. The Brazilian Northeastern region (Acurua) is the case study for the complementarity, among wind and solar energy resources, on hourly and monthly bases through nine scenarios combining representative capacity factors of both resources. The results show the ideal range for the optimized participation of photovoltaic installed power on hybrid power depending on capacity factors assumed. The range of number of each equipment may be used as preliminary information to long-term planning for companies interested on hybrid farms on Acurua region.

This paper present a discussion about solar energy installed together with an energy storage (ES) in batteries, and these systems are connected to the distribution network. In addition to analyzing a way to mitigate one of a problem found in this source, the insecurity due to unpredictability of the weather. For that, the idea is to analyze and use a battery found in the market. In order to carry out a complete and objective analysis, it adopted the model found in the Integrated Resource Planning, computation and valuation, which analyzed four dimensions (Environmental, Political, Social and Technical / Economic) of the distribution network and the energy storage. For that, a shopping mall was adopted as a case study where, besides the supply of energy through the distribution network, a photovoltaic system and a battery were also adopted.

The objective of this study is obtaining a methodology of analysis and determination of real-theoretical performance in power generation applied to photovoltaic systems of rigid and thin film panels and wind turbine systems, applying the theory that feature the systems and using solarimetric and anemometric data from the environment where the systems are installed. Aiming at the determination of theoretical energy production of the systems studied. This methodology basically consists of analyzing three sides: I – To analyze the characteristics of the installation environment from data of environmental variables that help in the calculation of performance; II – Applying technical characteristics of the generation systems with the application of different types of panels, operation and control systems; III – Different topologies of operation that vary according to the implemented system; aiming to determine with greater level of detail how the operation of generation system will be in the short term. Establishing a theoretical procedure to determine the potential used for power generation and analyzing the system behavior in relation to this theoretical potential, taking into account systemic and implementation factors for future comparative analysis between values measured in the project. This project resulted in the theoretical quantitative generator in short term and the performance generator of each system. Based on the analyzing described the photovoltaic systems had performance of 14% monocrystalline and 8% polycrystalline and wind system had around 44%.