Limitations of the current method for energy efficiency assessment of electric appliances for instantaneous water heating used in whirlpool tubs


Electric power generation in Brazil is becoming more expensive in the last years due the recent water crisis because of a decrease of rainfall and the increase of electric energy consumption. These facts have become increasingly essential for the development of efficient electrical equipment. Whirlpool tub water heating appliances are an example of the devices that can be improved and evaluated. The current method used for the evaluation of this type of equipment was applied in two different heater samples and the results were analyzed. The specificities inherent to the operation mode of these devices are not considered when the energy efficiency evaluation test is performed using the current Brazilian Standards. This method recommends the energy efficiency evaluation from calculated values of the electric energy consumption, obtained from instantaneous readings of the voltage and the electric current. This same method is used for an electric shower evaluation. The heater was installed in a test bench with a collecting vessel, similarly to an electric shower, fed with running water with no recirculation, factors which may hold off the obtained results from those effectively achieved when using these devices in real condition. The current test method come up with difficulties in its application and reproduction of results when used for water heater and for whirlpool tub evaluations in such a way that justifies the need of a new method that adopts the operating characteristics of this type of equipment.


LADEIRA, Flavio da Silva; ZANELLA, Luciano. Limitações do método vigente para avaliação da eficiência energética para aquecedores elétricos instantâneos de água para banheiras de hidromassagem. Revista IPT Tecnologia e Inovação, v.2, n.9, p. 24-38, dez., 2018.

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