| Abstract [eng] |
The aim of this master's research work is to evaluate the application possibilities of electrical energy storage systems (EESS) and their impact on the energy independence of prosumers. In recent years, the number of prosumers in Lithuania, especially those with solar power plants, has been rapidly increasing. This growth has made it increasingly difficult to properly balance grid loads, highlighting the need to improve energy use efficiency. The study is based on real data collected from a household with an installed 10 kW solar power system. Data was recorded every second for each phase of the three-phase grid. To assess the benefits of storage for energy flow balancing, a mathematical model was developed to simulate solar generation, consumption, and import–export flows, assuming an ideal battery that can be charged and discharged without power limitations. The simulation was carried out by varying the installed solar power capacity from 2 kW to 10 kW and the storage capacity from 2 kWh to 14 kWh. The following key indicators were used to evaluate the model: • SSR – self-sufficiency ratio, • SCR – self-consumption ratio, • PDSO – total daily energy exchange with the grid. The results showed that with properly selected storage capacity, energy import and export can be significantly reduced, substantially increasing both the SSR and SCR indicators. In some cases, import–export flows were reduced to nearly zero. This confirms the significant benefits of EESS in achieving greater energy independence and reducing electricity bills for grid-supplied power. The results of the study can be applied both for planning private individual solutions and for helping medium or large enterprises evaluate the cost-effectiveness of implementing EESS. |
