An optimal configuration of diesel generator and battery storage system for off-grid residential applications

Diesel generators are secure and a reliable alternative for rural areas where the grid extension is not available. Isolated load running under a diesel generator is effortless and looks economical since its low investment cost. However, hybrid systems like diesel generators and battery systems benefit in cost-savings and reduce carbon emissions in the long term. This paper discusses the long term benefits of the hybrid system consists of diesel generators and battery storage for off-grid residential applications. Also, this study proposes a new method to optimally size and operate the hybrid system. A new loading percentage optimization concept for the diesel generator has been introduced to increase its efficiency and lifetime. The multi-objective optimization has been performed under an off-grid residential load using MATLAB software. Results are discussed and compared to the same load with only a diesel generator. It found that the hybrid system's long-term investment and operating costs were reduced by 5.4% due to optimal sizing. Also, carbon emissions are reduced significantly by hybridization. Diesel generator's working hours have decreased by 68.5% due to the addition of battery storage and the generator's optimal loading.