Reliable hybrid systems (solar photovoltaic and diesel generators) have been shown to produce high-quality energy that supports different social and economic activities in Mwala village and Mbeya region in the United Republic of Tanzania, which contain three hundred households for the purpose of reducing poverty. The system was designed after load demand analysis with the help of Hybrid Optimisation of Multiple Electric Renewables (HOMER) software. For simulations on a diesel generator standalone system, a generator with penetration of renewable energy resources (solar photovoltaic) system, and a solar PV standalone system. The components of the hybrid system configuration include a generator of 24 kW, a solar photovoltaic of 29.5 kW, an inverter of 10.4 kW, and a generic 1 kWh lead acid with 120 strings. The paper features a detailed analysis of fuel consumption, optimisation of the system, capital cost, operating cost, electrical energy obtained, gas emissions, and sensitivity analysis. The result obtained from the model revealed that the total energy generated was about 75366 kWh per year, with an excess of 7240 kWh per year, which increased the reliability of power and allowed the availability of energy for new buildings and electrical appliances. The gas emissions from a generator standalone system were three times higher than those of a reliable hybrid system. Based on the energy demand, the solar PV diesel hybrid system with batteries has proven to supply reliable power 24/7.