Optimizing Solar PV Integration and Reliability in Diesel–Gas Hybrid Systems with Limited Grid Support During Power Outages

Reliable electricity access remains a major challenge in developing countries, which house over 80% of the global population. Rapid urbanization and industrialization, coupled with sub-optimal utility planning, often lead to frequent and prolonged power outages, forcing institutions such as universities, residential complexes, and small businesses to rely on diesel or gas generators. While solar photovoltaic (PV) systems offer a cleaner, cost-effective alternative, their integration is constrained by solar intermittency and the slow ramp-up response of conventional generators, which limits solar penetration to around 20% without fast-response backup. Battery storage can mitigate these fluctuations but requires significant capital investment, making it economically unfeasible for the large-scale consumer context considered in this study. To overcome these limitations, this work presents a hybrid energy management strategy that coordinates solar PV, captive gas and diesel generators, and brief, controlled intervals of grid support within defined load-shedding energy limits. This coordinated approach allows generators sufficient time to ramp up during solar irradiance dips while maintaining full compliance with ramp rate and grid energy constraints—eliminating the need for large-scale battery storage. A simulation-based case study at Lahore University of Management Sciences (LUMS), using measured load data and an irradiance-derived PV profile from PVSOL, validates the proposed strategy. The results demonstrate that the proposed framework enables PV penetration of up to 40% of the average load—double the conventional 20% limit—with operational fuel and grid import savings of approximately 41% (short-term OPEX), while satisfying the grid energy cap and generator ramp rate constraints.