Simulation of Distributed Generation with Photovoltaic Microgrids—Case Study in Brazil

Gustavo Xavier, Delly Filho, José Martins, Paulo Monteiro, Antônia Diniz
2015 Energies  
Elevated prices and lack of proper legislation and government incentives have been the main barriers in the development of the photovoltaic market in Brazil. In an attempt to overcome those barriers, a microgrid model was proposed and simulated. In the proposed microgrids, residential consumers are connected to each other to maximize the investment return by trading the surplus of generated energy among them. Different topologies and scenarios were studied from electrical energy and economic
more » ... rgy and economic standpoints. Stochastic data of solar radiation were simulated for the city of Viçosa, Minas Gerais, Brazil, for the period of one year, considering the statistical behavior of a series over 20 years. The system output power and energy balance were calculated considering a model for photovoltaic generators and the radiation simulated data. By determining the generated energy and electrical needs of the microgrid members, the cash flow and economic feasibility were calculated. Sensitivity analyses were performed by varying economic parameters to determine situations where investment becomes feasible. This paper OPEN ACCESS Energies 2015, 8 4004 shows that microgrid contributes to improve the economics and the initial investments. The number of participants in a microgrid, the electricity and the equipment costs are important parameters to speed up the economic and technical feasibility process. Introduction Worldwide, there is a predominance of power generation in centralized systems, usually from large fossil fuel or nuclear power plants. The development of small-unit power generating systems and changes that have occurred in power system operation and regulation have created opportunities for consumers to generate their own power [1]. In Brazil, most electricity generation is hydroelectric. Because of the size of the country, a long transmission system is required to carry this energy to consumer centers. Power rationing that occurred in 2001 showed the fragility of the generation system in Brazil, strengthening the discussions on alternative energy sources [2] . These factors show the importance of diversifying energy sources through Distributed Generation (DG). A significant change is foreseen for the current structure of highly centralized, large capacity power plants. A new structure, with the highly decentralized insertion of small-and medium-capacity power units, is expected [3] . Regarding the use of renewable energy, Brazil is one of the most advanced countries in South America [4] . Data from the National Energy Balance 2011 show that the primary energy on the Brazilian matrix is composed by 45.5% renewable energy (hydraulic, firewood, charcoal, sugarcane and other renewable sources, such as agricultural residues) [5]. Figure 1 shows the distribution of the sources of primary power generation in Brazil. It should be highlighted that the percentage of useful energy consumed in Brazil obtained from renewable sources should be even greater because much of Brazilian renewable energy is hydroelectric. Moreover, power conversion efficiency, from electrical energy to final end use, is usually higher compared to other energy sources. Thus, the percentage of useful energy from renewable sources tends to be higher than the 45.5% mentioned.
doi:10.3390/en8054003 fatcat:swby2yta2zai3dak7lxmn2zny4