 | Electricity is also polluted, like air and water.
José Pomílio informs what standby mode can represent
up to 15% of energy consumption in a home CARLOS TIDEI  Another problem that the crisis has made increasingly important is that related to the quality of electrical energy. Conceptually, electricity grid pollution is analogous to air and water pollution. “Electricity is a common good, where everyone shares the same resources. If I install a device that is polluting (in electrical terms), I could be harming everyone on the network, because they share the system”, comments professor José Tomílio. A current example is the compact fluorescent lamp, which consumes less energy, but imposes large deformations on the current that circulates through the network. “It uses less water in the hydroelectric plant, but from an electronic point of view it is very bad. The power factor is 0,5, while the ideal is 1. Compact lamps would be better with the introduction of a small modification in the circuit, which is already made in lamps sold to Europe, but not carried out in Brazil due to lack of a technical standard that requires it”, details Pomílio. He adds that there are several international standards limiting the distortion of the current shape that equipment or an industrial installation can produce, which have not yet been properly applied in our country.
 “We sent a proposal, on behalf of the Brazilian Society of Power Electronics, to the Brazilian Association of Technical Standards (ABNT), which replied that it had been forwarded to the responsible sector and also to Abilux (Brazilian Association of the Lighting Industry), an entity who must sit at the table to discuss these standards. To date, there are no studies for compact lamps, only for tubular lamps, which are already properly regulated”, informs the researcher.
Power electronics is an area that researches energy processing, with one of its focuses being reducing consumption through more rational equipment, maintaining or even improving the performance of processes and systems. For José Pomílio, the question is how to have more efficient electrical equipment with greater electrical output. “Why do you change the incandescent lamp for a fluorescent one? Because it provides the same quality of lighting with lower energy consumption. Eighty percent of the power of incandescent is heat, while in fluorescent, called cold light, the consumption is practically just for light.” Procel (Electrical Energy Conservation Program) also acts in this sense: encouraging the development and use of appliances such as refrigerators, washing machines or any other electrical equipment that use less electricity and have the same efficiency and performance. Stabilizers
– In relation to energy quality, some situations are especially critical, such as in hospitals where there are hundreds of devices operating simultaneously. In a tomography, for example, when other equipment that pollutes the electrical network is simultaneously connected, the exam may present a distorted image that does not correspond to reality, leading to a mistaken diagnosis. In many cases, the device manufacturer itself indicates the need to use a professional UPS that guarantees adequate voltage to the equipment, with a separate power supply from the local electrical network. ABNT recently defined technical standards for stabilizers, widely used in computers to guarantee a good supply voltage to the equipment. These standards became mandatory from this month of July. The main benefit is the establishment of minimum quality standards for such products, removing technically ineffective and even dangerous devices from the market. The role of a stabilizer is to compensate variations in the electrical network in order to keep the load stabilized. But generally the device itself has this feature. The stabilizer functions, in these cases, more as an additional safety factor, including protection against electrical discharges.
“Stabilizer manufacturers will certainly use the voltage reduction proposed by the government as a marketing tool to sell their products. Line filters, advertised as reducing consumption, do not provide any savings”, warns Pomílio. The stabilizer itself, according to him, does not contribute to energy savings. “It’s just another piece of equipment turned on, consuming a few more watts,” he says. -------------------------------------------------- - It can be more tiring than changing the light bulbs CARLOS LEMES PEREIRA For residential consumers, strictly following certain simplistic recommendations that the federal government is insisting on popularizing, in the campaign to save electricity, can result in more than the simple tiring of exchanging all the traditional light bulbs in the house for those of a model considered less “. waste”, and even at the expense of having damaged electronic devices. The alert comes from Professor Francisca Aparecida de Camargo Pires, from the Department of Energy Systems and Control at the Faculty of Electrical and Computer Engineering (FEEC) at Unicamp. According to her, the homemade effort will be of no use if the concessionaires are not forced to adapt the voltage in the secondary networks to the level of the new reduced consumption rates that are being imposed.  “The first measure recommended by the government to residential consumers was to exchange incandescent lamps for compact fluorescent lamps. It turns out that this, in general, causes disturbances in the network”, explains the engineer. “If we monitor the current waveform of these lamps, we will see that there is nothing sinusoidal; the shape is completely perforated and, for most consumers, it will behave like non-linear loads. This could cause some problems in the distribution itself and even affect the transmission system.”
The technical explanation, according to her, is as follows: “Non-linear loads can cause overvoltages; Furthermore, usually, when a normal load (the one that corresponds to normal consumption) is connected, you have the voltage at a certain level, because this was regulated, not on the poles, but in substations in charge of maintaining the supply to a certain area. When you lighten the load a lot, the tension in the network tends to increase.”
Recalling that “people's greatest anxiety is having to save depending on the average consumption recorded last year”, the expert emphasizes: “But that, until then, was the average that you and your neighbors normally had as consumption under a certain voltage. Now, with many people reducing this consumption, we will have an increase in voltage (which may or may not be in the range of 5% legally predicted), and which may also present considerable distortions due to the presence of compact fluorescent lamps”. In addition to the “miracle lamps” running the risk of not performing any miracles, the engineer warns: “More sensitive equipment, which depends on voltage control, could fail. Including computers with stabilizers, because there are a lot of stabilizers on the market that don't do everything they advertise.”
The solution, for her, would be for “someone up there” to force concessionaires to modify their parameters, to adapt the transmission to new consumption levels. There is no shortage of examples to follow, according to her: “In the USA, the blackout method can often be overcome by the brownout technique, that is, instead of erasing everything, the most critical points of tension in the networks are mapped, reducing it in line with the consumption observed in each part of the urban centers”.
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