Because there is no national standard for the voltage (or voltage) that reaches the outlets in our homes. When Brazil started to assemble its electrical network, in the beginning of the 20th century, different companies were established in each region of the country. “The choice of a 110-volt or 220-volt system depended on the country of origin of the first companies and on a cost analysis: the number of consumers per square meter, the money for the installation and for the necessary materials, such as transformers and cables. ”, says Ronaldo Roncolatto, engineering manager at CPFL. In these early days of electrification, the Canadian companies Rio de Janeiro Tramway, Light & Power and São Paulo Light & Power installed 110-volt networks for residential consumption in the two main cities of the Southeast Region. The first concessionaires that distributed energy in the Northeast Region opted for the 220. In both cases, the systems remain the same until today because, once installed, it is unfeasible to reform the entire distribution network – it would cost a hell of a lot. And there is no strong reason to justify this expense. “There are advantages and disadvantages to each type of system. One cannot always say that one is more advantageous than the other”, says Ronaldo. Therefore, it is not possible to say that there is a clear trend as to what will be the dominant tension in the future. Below, we list the strengths and weaknesses of the 110 and 220 in five crucial questions.
… Five differences between 110 and 220 volts. Tension!
What is the safest voltage?
At 110 volts. When a finger accidentally lands in the socket, the 220-volt shock is twice as strong as a 110-volt shock. This is because, in the case of the human body, the higher the voltage in the socket, the greater the electric current that causes the shock. It is the opposite of what happens with electrical appliances.
What is the best voltage to avoid blackouts?
At 220 volts. Generally, a “blackout” occurs when homes request an excess of electrical current from the distribution network. Connecting appliances to 220 volts is a way to avoid this overload because, the higher the voltage, the lower the current that electrical appliances use to function.
What is the least expensive voltage to maintain?
It’s 220 volts – at least for dealers. This system uses fewer transformers and cheaper cables on the way from the distributor to the final consumer.
What is the voltage that consumes less environmental resources?
It makes no difference. For our natural resources (for example, water from hydroelectric plants), neither voltage nor current matters. What really counts is the total power of the appliances connected to the electrical grid.
What is the most economical voltage for the consumer?
It makes no difference, because consumption is measured in kilowatt-hours – that is, by the power and operating time of the devices connected. To reduce the light bill, you need to use less appliances or opt for less powerful models.