Paulo Rotella Junior

Federal University of Paraíba · Department of Production Engineering

This study evaluates the stochastic economic viability of residential wind power generation in Brazil. Three scenarios representing different regions from Brazil were considered: high, low, and intermediate wind speed. For each scenario, 10,000 simulations were conducted using the Monte Carlo Simulation (MCS) method to obtain possible Net Present V...

Sources such as solar and wind energy are intermittent, and this is seen as a barrier to their wide utilization. The increasing grid integration of intermittent renewable energy sources generation significantly changes the scenario of distribution grid operations. Such operational challenges are minimized by the incorporation of the energy storage...

The Brazilian electric energy compensation system (EECS) states that 100% of the energy generated and inserted into the grid should be returned to prosumers as credits to their energy bill. Ongoing regulatory changes propose that compensation should only be provided for the energy cost (43%). From this perspective, with awareness of the complementa...

The challenges presented by increased electricity generation from intermittent renewable energy sources can be minimized by incorporating energy storage systems (ESS). Despite the benefits, this is still an emerging technology with limited use in Brazil. The aim of the present study is to use a multiobjective optimization process to support the pla...

The development and implementation of public policies towards renewable energies are crucial in order to address the contemporary challenges faced by humanity. The 3Rs (reduce, reuse, and recycle), as a circular economic practice, are often cited as one of the best solutions for sustainable development. Therefore, this study analyzed public policie...

This article presents a new approach for building robust portfolios based on stochastic efficiency analysis, by using the Chance Constrained Data Envelopment Analysis (CCDEA) model and periods of market downturn, i.e., worst-state market. The model is able to accommodate investors who exhibit different risk behaviors and the empirical analysis is d...

This study aims to provide a review of the state-of-the-art literature regarding the impact and contributions of corn ethanol on retail gasoline prices in the US. For this, a Systematic Literature Review following Prisma statement was carried out, seeking to answer four research questions: (1) what are the main characteristics of the literature reg...

Offshore wind energy has been identified as one of the most promising and increasingly attractive sources of energy. This technology offers a long-term power-generation source, less environmental impact, and fewer physical restrictions. However, given the complexity of this technology, economic feasibility studies are essential. Thus, this study ai...

Cassava is a staple food in many countries, and this food source differs from other crops in that its processing generates a highly polluting and toxic residue (manipueira) that requires further treatment. The present study analyzed the economic feasibility of anaerobic digestion of manipueira for producing clean electricity through distributed gen...

To investigate the efficiency of policy schemes to attract renewable energy investments, it is essential to analyze the impacts on returns and risks with consideration of the circumstances that affect the projects. The present study aimed to evaluate the impacts of net metering, tax incentives, and subsidized loans on the return and risk of the dis...

Economic feasibility analysis is essential in the decision-making process regarding investment in photovoltaic projects. Project profitability must be measured based not only on the costs and revenues, but also on the climatic particularities of the different locations. Therefore, performing simulations of technical and economic performance of phot...

This article analyzed the location and concentration of forest bioelectricity in Brazil, from 2000 to 2019, available from the National Electric Energy Agency (ANEEL) and used the following indicators: Location Quotient (QL), Concentration Index [CR (k)], Herfindahl-Hirschman Index (HHI), Hoover Index (H) and Coefficient of Gini (G). The main resul...

The Brazilian semi-arid region is marked by a variable spatial-temporal rainfall distribution, concentrated over a 3 to 4 month season. Limited water availability is the main obstacle to the production of forage plants of C3 metabolism (such as corn and soybeans) and C4 metabolism (such as sugarcane), as well as livestock. To mitigate this forage s...

The integration of intermittent renewable energy sources (RES) into the grid significantly changes the scenario of the distribution network's operations. Such challenges are minimized by the incorporation of utility-scale Energy Storage Systems (ESS), providing flexibility and reliability to the electrical system. Despite the benefits brought by ES...

Statistical process control is directly affected by the quality of measurements; therefore, acceptance of a measurement system is a pivotal issue. A gage repeatability and reproducibility study (GR&R) can determine whether the total variability observed in a process comes from manufacturing or from the measurement system. This systematic literature...

This research combines corporate sustainability performance and sustainable business model concepts to improve the corporate sustainability of organizations. The main objective of this article is to propose and apply a tool to identify sustainable innovation opportunities through a structured brainstorming process while providing a systemic busines...

This article creates a conceptual model, called a network system, to represent the Brazilian banking production system, based on its internal operational processes. The first, called the intermediation process, measures a bank's efficiency in extending loans from its available resources. The second, called the revenue process, measures a bank's eff...

The densification of raw material into fuel briquettes is one of the routs to convert biomass into energy. This method provides uniformity to the solid fuel, better physical and energy properties, facilitating its storage and transport, in addition to a more homogeneous combustion. Given the importance of these characteristics, this work presents a...

A energia solar fotovoltaica é uma das principais alternativas de energia renovável do mundo. Sua capacidade de renovação infinita e o barateamento nos últimos anos das placas solares, aliado ao aumento das tarifas de energia elétrica no Brasil, fez com que nos últimos anos a energia solar ganhasse bastante força. Este trabalho tem por objetivo ana...

The operation of electrical systems is becoming more difficult due to the intermittent and seasonal characteristics of wind and solar energy. Such operational challenges can be minimized by the incorporation of energy storage systems, which play an important role in improving the stability and reliability of the grid. The economic viability of hybr...

In 2019, the Brazilian National Electric Energy Agency proposed that the cost of accessing the electrical grid should be shared among all consumers. This would do away with cross-subsidies, where normal consumers without installed solar distributed generation (DG) units effectively cover the costs of access to the grid for consumers with DG units....

During the multi-objective optimization process, numerous efficient solutions may be generated to form the Pareto frontier. Due to the complexity of formulating and solving mathematical problems, choosing the best point to be implemented becomes a non-trivial task. Thus, this paper introduces a weighting strategy named robust optimal point selectio...

Brazil is currently undergoing changes to regulations on distributed generation (DG), specifically for solar energy micro-generation. The changes proposed by the Brazilian Regulatory Agency suggest that only the cost of energy be compensated to investors. The service costs and other charges related to energy tariffs must be divided among consumers....

This present study proposes the stochastic approach Omega-LCOE to compare a Levelized Costa of Electricity (LCOE) between different locations. To validate the proposed approach, an investigation to compare the wind energy LCOE of 63 main cities in São Paulo state (Brazil) in relation to world LCOE average. Therefore, the Omega value estimated by a...

In food industry, high variability is quite common due to seasonality of raw materials and perishable products. Statistical Process Control (SPC) is an effective methodology to reduce variability and to make predictable processes. Literature still lacks of practical approaches of SPC implementation in food operations. Thus, this paper aims to propo...

The high proportion of CO2/CH4 in low aggregated value natural gas compositions can be used strategically and intelligently to produce more hydrocarbons through methane oxidative coupling (OCM). The main goal of this study is to optimize direct low-value natural gas conversion via CO2-OCM on metal oxide catalysts using robust multi-objective optimi...

This study analyzes the concentration and conglomerate spatial distribution of forest-based thermoelectric plants in Brazil, in 2018. Herein, we spatially identified thermoelectric plants in different Brazilian regions and states, and measured the state concentrations (levels 1 and 2 of forest) using various indicators, including the concentration...

This research presents an experimental study for measurement system analysis of angle of repose in fertilizers with variable granulometry (1.5mm <d50 <5.0mm). In the literature, there are different procedures for determining this angle of repose, which often result on a variety of measurements for one measurand. Thus, the main objective of this wor...

The growing energy demand in the world and the concern for environmentally damaging energy sources have led to an increased interest in seeking alternative renewable energy sources such as wind energy. Furthermore, choosing effective locations for wind power plants has become a key issue in project planning. However, prior to implementation, such p...

This study proposes a Real Options approach to investigate the economic feasibility of a wind power plant investment with the option of abandoning along the project lifetime cycle. This novel approach considers uncertainties representation with respect to electricity sales revenue in the spot market, and the uncertainty represented by the settlemen...

Brazil may undergo changes in its distributed generation regulations, including the production of electricity from small solar power plants. The proposed amendment by Regulatory Agency provides for only the cost of energy should be compensated. The costs of services and charges included in tariff should be prorated among all consumers. Consumers al...

The introduction of environmental impact targets around the world has highlighted the needs for adopting alternative sources of energy, which can supply the demand and mitigate the damages caused to the environment. Solar energy is one of the main sources of alternative energy, and is considered an abundant source of clean energy. However, to facil...

A falta de apuração dos custos gera para a agricultura familiar uma desvantagem competitiva para com seus concorrentes. Assim, o objetivo da presente pesquisa é apurar os custos em um estabelecimento da agricultura familiar produtora de queijo e iogurte, localizada na região do Baixo Jequitinhonha, visando identificar o custo dos produtos produzido...

Methods for supporting the bidding processes of hybrid wind-photovoltaic (W-PV ) farms are scarce, especially when numerous goals are included in the optimization problem. Therefore, the primary objective of this study is to develop a novel model that can help bidding of W-PV farms considering a range of objectives that maximize the environmental a...

Hard turning processes have several advantages against traditional turning. Improved surface integrity and short process time are some examples. Surface integrity is one of the most important issues in modeling of machining processes. Multiple roughness parameters are observed in relation to several controllable and uncontrollable input parameters....

One of the challenges of energy regulatory-agencies is to guide the agents decision-making process towards maximization of the overall welfare of the electricity sector. However, this is not a simple task since it requires meeting expectations of many stakeholders, from investors to consumers. This paper proposes an optimization methodology aimed a...

To reduce the risks of a new energy crisis and increase energy availability, the use of renewable energy sources (RES) is important and recommended. In Brazil, micro and small companies contribute about 25% of gross domestic product (GDP), and electric energy is employed intensively, so the importance of microgeneration is observable. This research...

DMAIC (define, measure, analyze, improve and control) is one of the most utilized methods for guiding practitioners in the decision-making process of quality improvement projects. Industrial processes commonly deal with multiple critical-to-quality (CTQ) characteristics. When these characteristics are correlated, multivariate statistical techniques...

Wind power has grown popular in past recent years due to environmental issues and the search for alternative energy sources. Thus, the viability for wind power generation projects must be studied in order to attend to the environmental concerns and still be attractive and profitable. Therefore, this article aims to perform a sensitive analysis in o...

Measurement system analysis has a pivotal role in assessing the measuring error when conducting empirical studies. Gage Repeatability and Reproducibility (GR&R) studies are classic methods applied to evaluate measurement system adequacy for a particular application. However, previous published studies are limited to determine the source of measurin...

Owing to the wind and photovoltaic (PV) potential in Brazil, the country has recently seen increased exploration into the construction of wind-PV hybrid plants. However, as specific criteria for contracting this type of project have not yet been developed, this paper presents a model to assist the government in contracting projects that maximize th...

Hard turning operations have been extensively investigated owing to their ability to reduce process cycle time, increase process flexibility, ensure high-dimensional accuracy, and enable machining without a cutting fluid. These processes are rather common for dealing with multiple quality characteristics. To evaluate the process ability and meet cu...

Brazil presents remarkable potential for wind power generation. This study aims to evaluate the behavior of wind average speed at the four major wind energy-producing states. The main contribution of this research is to use the NGR&R study (Nested Gage Repeatability & Reproducibility), generally applied on manufacturing quality management. Wind ave...

The objective of this paper is to present a proposal to form robust portfolios using a stochastic efficiency analysis of assets from companies in the Sao Paulo Stock Exchange, focusing on the worst market state. In order to do this, information about the market in all of its phases and information from low market periods were employed in a stochast...

Purpose – The aim of this research is to analyze the feasibility of developing a real oil field in Africa under a production sharing agreement, through the application of the real options theory. Design/methodology/approach – The research was conducted according to the principles of modeling and simulation, based on a structure that consists of th...

Recently, different methods have been proposed for portfolio optimization and decision making on investment issues. This article aims to present a new method for portfolio formation based on Data Envelopment Analysis (DEA) and Entropy function. This new portfolio optimization method applies DEA in association with a model resulting from the inserti...

A mixed ceramic is a type of cutting–tool material widely employed for machining hardened steels. The usage of a mixed ceramic along with a wiper geometry can help double the feed rate, thereby increasing productivity while keeping the surface roughness (Ra) as low as possible. Analyses of manufacturing processes, such as a machining process, show...

Investors must be able to plan and analyze their investments in order to optimize decisions and turn them into profits associated with a particular project. Since electricity producers in the Brazilian electric power system are exposed to a short-term market, the goal of this paper is to propose a framework for investment analysis capable of encomp...

Mathematically, each Pareto optimal point is an equally acceptable solution to a multiobjective optimization problem (MOP). However, the process of choosing a single preferred solution among all computed alternatives can be a difficult task because of a high cognitive effort required. Thus, the main objective of this work is to optimize the process...

Low oil prices have been a major reason for the reduced investments in oil and gas projects around the world. This study analyzes how oil price uncertainties impact decision making concerning an African oil exploration and production project conducted under the Risk Service Contract (RSC) by incorporating managerial flexibility through the applicat...

The objective of this paper is to present a proposal to form robust portfolios using a stochastic efficiency analysis of assets from companies in the Sao Paulo Stock Exchange, focusing on the worst market state. In order to do this, information about the market in all of its phases and information from low market periods were employed in a stochast...

The objective of this book is to present a new proposal for creating robust portfolios from stochastic analysis of share efficiency from companies, negotiated in the BM&FBovespa - Securities, Commodities and Futures Exchange. In order to do this, information of shares in worst state market periods were grouped by hierarchical clustering, and then s...

In practical situations, solving a given problem usually calls for the systematic and simultaneous analysis of more than one objective function. Hence, a worthwhile research question may be posed thus: In multiobjective optimization, what can facilitate the decision maker in choosing the best weighting? Thus, this study attempts to propose a method...

Purpose – The purpose of this paper is to analyze portfolios chosen using an efficiency evaluation that considers risk and uncertainty and optimizes the allocation of invested capital using the Sharpe approach. Design/methodology/approach – The portfolios comprised shares on the Sao Paulo Stock Exchange. A chance-constrained data envelopment analy...

In practical situations, solving a given problem usually calls for the systematic and simultaneous analysis of more than one objective function. Hence, a worthwhile research question may be posed thus: In multiobjective optimization, what can facilitate for the decision maker choosing the best weighting? Thus, this study attempts to propose a metho...

The coffee industry in Brazil is characterized by its social importance, once the agribusiness sector is the one that employs more labor, and by its economic importance, with significant participation in agricultural production, reflecting positively on the trade balance. Some characteristics of the coffee activity, such as dependence on climatic f...

This article shelds light on how, in Brazil, synergies arise through mergers and acquisitions (M&A) and how best to evaluate them. Through a review of the literature, we analyzed how generated synergies are assessed across different methodologies. This article also analyses the synergy gains in Brazilian mergers and acquisitions between 2000 and 20...

This article aims to analyze the behavior of a portfolio selected through Data Envelopment Analysis (DEA) associated with fuzzy logic and optimized using the Sharpe approach. As a basis for comparison, two other portfolios were used, one obtained through only the Sharpe approach. In this research study, a fuzzy DEA model was used to evaluate effici...

Due to the relative uncertainty involved with the variables which affect financial market behavior, forecasting future variations in a time series of the Brazilian stock market Index (Ibovespa) can be considered a difficult task. This article aims to evaluate the performance of the model ARIMA for time series forecasting of Ibovespa. The research m...

This work proposes a model of performance indicators system for technology- based incubators, based on the concepts of the Balanced Scorecard control results and aligned with guidelines for performance evaluation proposed by the New Ventures Support Reference Center (CERNE) method to be used in the management of resident companies, even those at th...

This article aims to analyze the behavior of a portfolio of assets selected by Data Envelopment Analysis (DEA), optimized by the Sharpe approach, and compare it to portfolios of assets obtained only by DEA or the Sharpe approach. To do that, we used the DEA model to assess the e ciency of shares of the São Paulo Stock Exchange (Bovespa), employi...

This article sheds light on how synergies arise through mergers and acquisitions (M&A). Enterprises go through the process of Mergers and Acquisitions (M&A) with the goal of improving performance, increasing efficiency and obtain-ing business synergy. Prior literature suggests that synergies could arise due to taxes, market power or efficiency im-p...

A major task in assessing risks of investment projects is defining the approach to calculating the project’s volatility. Looking at assorted estimation techniques, this paper calculates their volatilities. The techniques originate from authors in the area and involve project-specific variables of uncertainty. These techniques are applied to a case...

This article sheds light on how synergies arise through mergers and acquisitions (M&A). Enterprises go through the process of Mergers and Acquisitions (M&A) with the goal of improving performance, increasing efficiency and obtain-ing business synergy. Prior literature suggests that synergies could arise due to taxes, market power or efficiency impr...