Voltage Asymmetry Influence on Resource Con-Sumption at Power Generating Plants

Abstract

The objective of this paper is to provide new research on the linkages between voltage asymmetry, energy efficiency, and resource efficiency to inform policymaking in this area about the possibilities of electricity saving potential. Asymmetry voltage coefficients value in Ukrainian grid were experimentally identified based on assessments of 23 Ukrainian companies during 2016-2018. It was estimated, that 26 % of transformers have asymmetry voltage coefficient of reverse sequence lower than 2 % and 12 % of transformers have asymmetry voltage coefficient of zero sequence lower than 2 %. The estimated resource saving potential for Ukrainian power generating plants is up to 1’978 GWhel/a, which is up to 1.5 % of total electricity produced. Equivalent reducing electricity generation at coal power plants could prevent emissions up to 292.79 t/a of ash emissions; 733 kt/a of CO2 emissions; 5.9 kt/a of SOx emissions; 2.9 kt/a of NOx emissions; 9.03 m3/a of nuclear waste.

Assessment of the energy efficiency potential of mining enterprises

“…For example, Canada [12] and Chile [13] are introducing renewable energy sources as their main power supply. However, the use of green energy sources leads to worsening the quality parameters of the electrical network, which in turn leads to a decrease in the service life of equipment and increase in electrical energy losses [14]. China [15,16] and some African countries (for example, South Africa and Zambia) reduce electrical energy tariffs for mining companies, thereby increasing the tariffs on energy sources for other sectors of the economy, or for the population [17].…”

“…Therefore, to assess the level of energy efficiency at the mining enterprise, the quality parameters of electrical energy have been analysed. When measuring the parameters of the electric power line on October 17, 2016 using Metrel MI 2892, the voltage asymmetry has been recorded (measurement method is given in [14]), which is shown in Fig. 1.…”