In the late 19th century, the three-phase induction motor was the central element of productivity increase in the second industrial revolution in Europe and the United States. Currently, it is the main load on electrical systems in global terms, reaching approximately 70% of electrical energy consumption in the industrial sector worldwide. During the 20th century, electric motors underwent intense technological innovations that enabled significant performance gains. Thus, this work analyses the performance changes in squirrel-cage rotor three-phase induction electric motors (SCIMs) with mechanical powers of 3.7 kW, 37 kW, and 150 kW and speed ranges corresponding to two poles and eight poles, connected to a low voltage at a frequency of 60 Hz and tested between 1945 and 2020. The study confirms accumulated performance gains of above 10% in some cases. Insulating materials for electrical conductors have gone through several generations (cotton, silk, and currently, varnish). Improvements to the housing for cooling, the bearings, the quality of active materials, and the design were the elements that enabled the high gains in performance. The first commercial two-pole SCIM with a shaft power of 4.4 kW was marketed in 1891, with a weight/power ratio of 86 kg/kW, and until the 2000s, this value gradually decreased, eventually reaching 4.8 kg/kW. Between 2000 and 2020, this ratio showed a reversed trend based on improvements in the performance of SCIMs. More active materials were used, causing the weight/power ratio to reach 8.6 kg/kW. The MEPS (minimum energy performance standards) of SCIMs had an essential role in the performance gain over the last three decades. Data collection was via tests at the Electrical Machines Laboratory of the Institute of Energy and Environment of the University of São Paulo. The laboratory has a history of tests on electrical equipment dating from 1911.

Accidents caused by electricity are responsible for countless deaths and injuries of people/animals and damage to buildings and facilities worldwide. Although sufficient knowledge is available on making electrical installations safe, many countries do not have organized data on accidents of electrical origin, making it challenging to implement effective public policies to reduce the risk of accidents caused by electricity. Therefore, this research aims to present a methodology for collecting data from electrical accidents through the Google LLC alert monitor. The research methodology includes obtaining and analyzing electrical-related accident data involving electric shock, fires of electrical origin, and lightning. The application of this approach in Brazil between 2016 and 2021 validates this methodology. The analysis of this data points to a significant increase in accidents of electrical origin in the analyzed period. All categories of fatal accidents between 2016 and 2021 showed a marked increase; 10.3% due to electric shocks; 33.3%; due to lightning; 42.2% in fires caused by overload or short circuits. In the case of deaths from electric shock and lightning, more than 75% were men, and in the case of deaths from electrical fires, most were elderly and children. The analysis also includes detailed information about age and sex, the location of the accident, date, and cause. Consequently, guidelines to prevent the principal types of accidents of electrical origin from occurring could be developed.

With the current concerns about sustainable development and energy consumption in buildings, water pumping systems have become essential for reducing energy consumption. This research aims to develop guidelines for the energy assessment of water pumping systems in multifamily buildings. The methodological procedures are: (i) definition of the efficiencies of electric motors; (ii) definition of pump efficiency levels; (iii) determination of energy consumption; and (iv) construction of the efficiency scale and guidelines for projects and assessments. The results obtained were that centrifugal pumps with 40% efficiency have higher energy consumption, regardless of the efficiency class of the electric motors, showing a 20% increase in electrical energy consumption. Lower efficiencies directly impact the energy efficiency rating of the water pumping system. Thus the 40% efficiency obtained energy efficiency rating “Very Low—VL” for all motor efficiency classes (between IE1 and IE5). At 60% efficiency, the energy efficiency level of the system was “Average—A”, gradually increasing to “Very High—VH”, as the energy consumption in the pumps decreased and the motors’ energy efficiency classes increased. It is concluded that designers and professionals in the area must consider the efficiency of the pumps, as they play a fundamental role in the classification of the system’s energy efficiency. It is also recommended to verify the energy efficiency of the water pumping system and implement design guidelines so that the pumping system achieves lower energy consumption, contributing to the building’s energy efficiency and sustainability.

Accidents caused by electricity use are responsible for many deaths and injuries of People and animals worldwide and damage they cause to buildings and their electrical installations. Although there is a lot of knowledge available on making electrical installations safer, many countries lack data on accidents of electrical origin, which makes it challenging to implement effective public policies to reduce the risks of accidents caused by electricity. Developing countries, such as Brazil, have difficulties obtaining, processing, and sharing reliable data on accidents of electrical origin. This work presents data analysis on accidents of electrical origin in Brazil between 2016 and 2020, using information obtained from different sources, such as government agencies and the Google LLC alert monitor. The analysis of these data points to an average annual increase in fatal accidents of electrical origin, most of which are caused by electric shock, followed by lightning and fires caused by overload or short circuits. The analysis also includes the data details such as age group, location of the accident, and cause. The work will also compare data from other countries to identify possible relationships between the level of development and causes of accidents.