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Three load matching indicators (self-consumption rate, self-sufficiency rate, loss of load probability) and the CO2 emissions were evaluated for 55 Cypriot households with 3 kWp rooftop photovoltaic (PV) generators. The calculations were performed using 30-minute generation and consumption data from a large scale smart meter project in Cyprus. To investigate the effects of recent advances in local legislation, an analysis for higher PV capacities (5 kWp and 10 kWp) was also performed. The PV generation profiles for 5 kWp and 10 kWp PVs were obtained by scaling the 3 kWp PV generation profiles. The results showed that the self-consumption of the analyzed households varied seasonally, as it was related to their heating and cooling demand. More interestingly, the ratio between the households’ annual electricity generation and demand, formally defined here as generation-to-demand ratio (GTDR), was found to be related to the value ranges of the studied load matching indicators. Hence, on average, households with 3 kWp PV generators annually self-consumed 48.17% and exported 2,415.10 kWh of their PV generation. On the other hand, households with larger PV generators were characterized by a higher GTDR, but lower load matching capabilities. For the cases of 5 kWp and 10 kWp PV generators, the average self-consumption fell to 34.05% and 19.31%, while the exported PV generation was equal to 5,122.47 kWh, and 12,534.90 kWh, respectively. Along with lower load matching capabilities, households that generated more than they consumed were also found to have a lower potential for CO2 emissions reduction per installed kWp within the boundaries of the building. In this context, the GTDR could be used by stakeholders to characterize buildings, infer possible value ranges of more complex indicators and make evidence based decisions on policy and legislation.

This paper reports on the electrical performance of two bloc-of-flats buildings located in Prague, Czech Republic. Measured data of electrical consumption were used to investigate the effect of photovoltaic (PV) and battery energy storage system (BESS) systems on the overlap between generation and demand. Different PV array configurations and battery storage capacities were considered. Detailed solar analysis was carried out to analyze the solar potential of the building and to assess the PV electricity production. The evaluation of the building performance was done through MATLAB simulations based on one-year monitored data. The simulation results were used for the calculation of the load matching indices: namely, the self-consumption and self-sufficiency. It was found that optimized array tilt and orientation angles can effectively contribute to a better adjustment between electricity demand and solar PV generation. The addition of a façade PV system increases significantly the PV generation and thus the load matching during winter months. Mismatch is further reduced by using the energy flexibility provided by the BESS. Depending on the PV size and BESS capacity, the self-consumption and the self-sufficiency of the building could increase from 55% to 100% and from 24% up to 68%, respectively.

Introduction. The variety of electric drives, the performance characteristics of which correspond to the set requirements of consumers while ensuring reliable and economical operation for a certain time resource, characterizes the variety of circuit solutions, including using matching transformers and reducers. Problem. The use of matching transformers and reducers units significantly changes the performance characteristics of the electric drive. Most articles are devoted to modeling an electric drive without such elements. It is advisable to consider simulations of electric drives using these elements. Methodology. In the models of matching transformers and reducers, the initial data are used, which determine both the functional properties and the mass and size parameters. The latter provide an opportunity to consider the economic aspects of the electric drive. For the correct calculation of the energy balance of the electric drive, the efficiency of the elements under consideration is taken into account. Results. The use of the developed algorithms for modeling the dynamic modes of two induction motors in electric drives operating on a specific load diagram, with the connection of a matching transformer and reducers, is considered. Dependencies of efficiency and power factor of motors have allowed to determine the medium cyclic energy indicators. The mass- size and cost indicators of variants of electric drives were found, which made it possible to calculate the average cyclic reduced costs of electric drives. Practical value. The possibility of choosing the best variant of the drive based on various indicators, including the minimum amount of energy losses per year, is substantiated. References 17, tables 2, figures 8. Key words: induction motor, load cyclogram, reducer, transformer, mathematical model, average cyclic criteria, energy indicators, reduced costs. [phrase omitted]