Proceedings of the International scientific and practical conference ―Multidisciplinary approaches in science, technology and culture‖ (September 5-7, 2025) / Publisher website: www.naukainfo.com. – Oxford, United Kingdom, 2025. - 124 p.

113 is shown that such a policy cuts fuel use, improves reliability, and reduces the carbon footprint without compromising power quality. The results can serve as a methodological basis for the design and operation of autonomous and semi-islanded systems. Keywords: hybrid energy systems; energy management systems; battery energy storage system; source prioritization; reserve management; reliability; carbon footprint. One of the key advantages of modern hybrid energy systems (HES) is their ability to dynamically adjust operating modes and utilize available power sources in the most rational sequence, depending on the balance between generation and consumption, equipment status, battery energy storage system‘s (BESS) state of charge, and forecasted changes in load or resource availability [1–4]. In situations where centralized electricity supply is limited or unavailable – such as in remote regions or during emergencies – the combination of renewable energy sources (RESs), BESS, and backup generators forms an autonomous energy circuit capable of sustaining power supply over extended periods, provided that fuel for backup units is ensured [5–7]. Effective power backup involves not only maintaining uninterrupted electricity supply and ensuring power quality parameters [5], but also implementing a rational hierarchy in the use of available sources. Priority is given to cheaper and cleaner renewable energy, while backup generators are activated only when necessary [1, 2, 4]. This strategy is made possible by an energy management systems (EMS), which operates in real time to collect data on current generation, BESS status, load demand, and forecasted changes, while also considering the economic efficiency of each energy source [1, 8, 9]. This ensures optimal energy flow distribution, reduced fuel consumption, minimized equipment wear, increased share of renewable generation, and a reduction in the system‘s carbon footprint. In a typical priority sequence, energy produced by photovoltaic panels and wind turbines is utilized first to meet the current load [1, 2, 4]. Any surplus is directed