Integrated TEEP approach to microgrid design and planning with small hydro/solar/diesel resources for standalone application

This study discusses microgrid (µgrd) planning using small hydro, solar and diesel resources for 100 offgrid houses in Nigeria. The work introduces the technical, environmental, economic and policy (TEEP) analysis approach. The technical aspect considers the component sizing, electricity generated, unmet demand (ud), loss of power probability (LOPP) and availability (Avb); the environmental part evaluates the emissions generated by the µgrd compared to when only a diesel-based µgrd is employed to service the load; the economic perspective of the study is based on the evaluation of the net present cost (NPC) and the cost of unit energy produced (CoE). The paper examines 4 different configuration scenarios such as: SHP only, SHP + PV, SHP + PV + diesel, and diesel only µgrds, which are determined based on standard sizing methodologies. The capacities of these generating systems are 50 kW SHP; 50 kW SHP and 50–150 kW PV; 50 kW SHP, 50 kW PV and 91 kW diesel generator (DGen); and 91 kW DGen, respectively. The energy generated by these configurations is 508,874, 572,409–699,480, 620,002, and 574,638 kWh/yr, respectively, against a baseline users’ demand of 574,638 kWh/yr. The corresponding LOPP/Avb values for the configurations are 14.2/85.8%; 6.28/93.72–0/100%; 0/100%, and 0/100%. The 1st and 2nd scenarios are 100% renewable energies but the 3rd and 4th scenarios emit CO2, CO, unburned hydrocarbon, particulates, SO2 and NOx of 35,294, 222, 9.71, 1.35, 86.4 and 209 kg; 444,841, 2,804, 122, 17, 1,089 and 2,634 kg, respectively. The NPC and COE of all scenarios range from 34,594 to $ 27,025,517, and from 0.0100 to $ 6.3135, respectively, while their fuel costs are $ 269,730 and $ 3,399,704 over a 25-year project lifespan. Results demonstrate that the 3rd scenario can achieve better reliability as it integrates a backup generator to enhance the complementary characteristics of supply with lower lifecycle and fuel costs, CoE, and emissions compared to the 4th scenario. The social-environmental-marketability-implementation (SEMI) framework is introduced to discuss the policy aspect; this provides a deeper insight into the prevailing situation, local conditions, and the sustainability factors associated with the proposed µgrd.