Distributed microgeneration and minigeneration offer a solution for the supply of electricity without the need for large investments. This paper uses the data envelopment analysis (DEA) technique to verify the performance of photovoltaic systems managed by the population. During the analysis, data were collected on 123 micro and minigeneration units distributed over an area of 98 500 km² in the Northeast Region of Brazil. Using the analysis undertaken in this paper, high dispersions of the performance among photovoltaic systems were verified in Pernambuco because the efficiency levels of approximately 90% of the facilities evaluated can be improved. The analysis sought to understand the factors that have an impact on the good performance of the generating units, in addition to which it identified the generation units that are efficient and that will serve as references for the inefficient units. It is important to emphasize that, although DEA does not directly identify the causes of inefficiency of a unit, it indicates the reference units to be mirrored by the unit, in order to identify the practices to be applied to improve its efficiency level. The systematic method presented in this paper can be replicated and expanded by using a monitoring system in order to guarantee the best way to take advantage of photovoltaic generation in distributed systems, thereby enabling the energy generated to be increased by up to 30%, as shown in this paper.

The development of electronic design evolves every day. The adequate selection of electronic components is at the heart of a project's success. Therefore, it is necessary to make a preliminary study of the characteristics of the components to be used in order to select the most appropriate ones for each application. For a smart plug project, an essential part is the current measurement system where the transducer represents a critical component. In this context, this paper makes a comparative study among three current transducer technologies: hall effect sensor, current transformer (CT) and shunt resistor. The applied current was measured by conducting a test using an existing sensor available on the market for each technology. In addition, a comparative analysis of the characteristics of the transducers was carried out and for some transducers both qualitative and quantitative analysis were undertaken. Finally, a multicriteria technique is used in the selection of transducers, taking into consideration the weight defined for each criteria in the project, using the mathematical process ROC (Rank Order Centroid). From the analysis, we can state that the hall effect sensor presents the best results when compared to the other transducers.