The structure of the park of power transformers with a higher voltage of 6-10 Kv on the example of the electric grid organization of the branch of pjsc «Rosseti center»-«Orelenergo», serving rural electric networks

THE PURPOSE. Evaluation of the power transformer fleet 6-10/0,23-0,4 kV on the example of a branch of PJSC «Rosseti Center»-«Orelenergo».METHODS. In the work, based on the database of the branch of PJSC «Rosseti Center»-«Orelenergo», an analysis was made of the fleet of power transformers with a higher voltage of 6-10 kV in terms of their number, circuits and groups of connection of windings, rated power, terms of service, as well as energy efficiency classes, taking into account the current standards of the technical organization of PJSC «Rosseti».RESULTS. According to the results of the study, it was revealed that among the transformer fleet of the branch of PJSC «Rosseti Center»-«Orelenergo», the number of which is 6026 units, 4528 (73% of the total number) transformers have a circuit and a group of winding connections Y/Y0. The most numerous are transformers with rated capacities of 63 kVA, 100 kVA, 160 kVA, 250 kVA (respectively 853, 1454, 1252, 802 pieces of equipment). It was also revealed that only 268 transformers out of 6206, i.e. 4.3% of the total amount comply with the standard of PJSC «Rosseti» in terms of modern requirements for the level of energy efficiency class.CONCLUSION. A variant of the strategy for replacing power transformers in the branch of PJSC «Rosseti Center»-«Orelenergo» is proposed, within the framework of which trasformers with a given design, circuit and winding connection group, rated capacities and energy efficiency classes are replaced. The implementation of the strategy proposed in the work will make it possible to reduce total electricity losses by 2.3%, as well as increase the share of energy-efficient transformers from 4.3% to 20.4% in the branch of PJSC «Rosseti Center»-«Orelenergo».

Review of deaths and behavior of large birds of prey on power grid facilities in Tatarstan and Udmurtia (Russia), problems of modernization of 6–10 kV overhead power lines

The report analyzes the deaths of large birds of prey on power grid facilities of Tatarstan previously published in the literature since 2012 and additional ones, identified since 2019, including in the neighboring region – Udmurt Republic. Analysis of the data shows that immature Imperial Eagles (Aquila heliaca) up to 3 years old (n=11) died on the 6–10 kV power lines dangerous for birds. The percentage of fledglings that died near breeding territories after leaving their nests was 81.8% (n=9); one bird died in its second year of life and one bird died in its third year. The death of fledglings was identified in 8 breeding areas (in one of them twice), which is 3.9% of all known breeding areas of the Imperial Eagle in Tatarstan by the end of 2021 (n=205) and about 7.2% of 111 breeding areas in 16 administrative districts of southeastern Tatarstan where oil production is taking place. Two out of six fledglings, for which a time interval of death was established, died in the second half of August, and 2 eagles also died in the first and second halves of September. Distances from precisely known nests to locations where the fledglings died ranged from 0.26 to 11.7 km, 2.56 km on average (n=7). In 57.1% of cases deaths occurred at distances less than 1 km (from 260 to 600 m), and in 28.6% of cases at distances from 2 to 3 km. Observations of the behavior of imperial eagles in breeding grounds show a certain selectivity, namely avoidance of the most dangerous power lines. Adaptation of imperial eagles to the electric grid environment continues – 3 new breeding territories on the electric poles of high-voltage power lines were found. Two cases of death of immature White-Tailed Eagles (Haliaeetus albicilla) were identified on 6–10 kV power lines dangerous for birds deep in the forestland on narrow forest cleared strips in Tatarstan and Udmurtia, as well as the Steppe Eagle (Aquila nipalensis) in Udmurtia. Illegal exploitation and even construction of new 6–10 kV power lines dangerous for birds continues. Despite the measures taken to protect birds from death in the electric grid environment, the rate and quality of these measures are such that in the near future power lines will have a negative impact on eagles in the native area as they do now.

Electrification Potential of U.S. Industrial Boilers and Assessment of the GHG Emissions Impact

Electrification is a key strategy for decarbonizing the industrial sector. Industrial process heating, which still relies heavily on fossil fuel combustion and accounts for the majority of sector wide GHG emissions, is a particularly attractive electrification target. Electrifying industrial boilers represents a cross-cutting opportunity for GHG emissions reductions, given their widespread use in most manufacturing industries. Yet, there are gaps in the understanding of the current population of conventional industrial boilers in the United States that preclude a characterization of boiler electrification’s technical potential to reduce fuel consumption and GHG emissions. In this study, we develop an up-to-date dataset of the industrial boiler population in the U.S. and quantify the county-level electricity requirements and net changes in fuel use and GHG emissions under the current electric grid and theoretical future grid scenarios. Our results show an increase of 105 MMmtCO2e and 73 MMmtCO2e in GHG emissions from boiler electrification, with and without the replacement of byproduct fuels, respectively, under the current electric grid. GHG emissions savings are currently possible only in certain regions of the U.S. unless future grids are decarbonized. We also provide recommendations for policy makers and manufacturing facilities that would advance the electrification of industrial boilers in locations and industries toward fuel savings and GHG emissions reductions.

WHISPER: Wireless Home Identification and Sensing Platform for Energy Reduction

Many regions of the world benefit from heating, ventilating, and air-conditioning (HVAC) systems to provide productive, comfortable, and healthy indoor environments, which are enabled by automatic building controls. Due to climate change, population growth, and industrialization, HVAC use is globally on the rise. Unfortunately, these systems often operate in a continuous fashion without regard to actual human presence, leading to unnecessary energy consumption. As a result, the heating, ventilation, and cooling of unoccupied building spaces makes a substantial contribution to the harmful environmental impacts associated with carbon-based electric power generation, which is important to remedy. For our modern electric power system, transitioning to low-carbon renewable energy is facilitated by integration with distributed energy resources. Automatic engagement between the grid and consumers will be necessary to enable a clean yet stable electric grid, when integrating these variable and uncertain renewable energy sources. We present the WHISPER (Wireless Home Identification and Sensing Platform for Energy Reduction) system to address the energy and power demand triggered by human presence in homes. The presented system includes a maintenance-free and privacy-preserving human occupancy detection system wherein a local wireless network of battery-free environmental, acoustic energy, and image sensors are deployed to monitor homes, record empirical data for a range of monitored modalities, and transmit it to a base station. Several machine learning algorithms are implemented at the base station to infer human presence based on the received data, harnessing a hierarchical sensor fusion algorithm. Results from the prototype system demonstrate an accuracy in human presence detection in excess of 95%; ongoing commercialization efforts suggest approximately 99% accuracy. Using machine learning, WHISPER enables various applications based on its binary occupancy prediction, allowing situation-specific controls targeted at both personalized smart home and electric grid modernization opportunities.

Comparative techno-economic analysis of power system with and without renewable energy sources

<p>The primary aim of this work is to feature the advantages of integrating natural source of energy from the solar and wind to the prevailing electric power systems. Two types of analysis are carried out in two test systems (standard and modified test systems) and the outcome of the test systems are compared. The two analyses are technical analysis and economic analysis. The stability of the voltage is analyzed under technical analysis and the price of energy consumed from the electric grid is calculated and analyzed under the economic analysis. Dynamic hourly load data, hourly solar radiation, hourly wind velocity, and dynamic electricity prices are considered for the standard IEEE system and modified test system (with the integration of RES). Voltage stability index (L-Index) and price of the electricity consumed from electric grid are found for standard test system and the outcome is compared with the outcome of modified test systems. MATLAB coding is done for techno-economic analysis for both test systems. It is inferred from the outcome that the integration of renewable energy sources fairly contributes to the economic benefit of the system by lowering the power purchased from the grid and enhance the stability of the system.</p>