Techno-economic potential of retrofitting diesel power systems with hybrid wind-photovoltaic-diesel systems for off-grid electrification of remote villages of Saudi Arabia

Recent climatic anomalies such as hot summers, cold winters, hurricanes, and cyclones are all reflections of global warming due to burning of fossil fuels. To combat unprecedented global warming and to mitigate future energy challenges, there is worldwide interest in utilization of renewable sources of energy such as solar-photovoltaic (solar-PV) and wind energy. Other driving forces paving avenue for renewable energy include rapid escalation in oil prices, growing concerns regarding depletion of oil/gas reserves, etc. Retrofitting of diesel systems with hybrid wind-PV-diesel systems is being widely disseminated to reduce diesel fuel consumption and to minimize atmospheric degradation. One of the potential market for deployment of hybrid systems is in remote locations which are driven by diesel generators. The Kingdom of Saudi Arabia (KSA) has a number of remote villages scattered all over the Kingdom. The aim of this study is to analyze wind speed and solar radiation data of Rafha, KSA, and to assess the technical and economic potential of hybrid wind-PV-diesel power systems to meet the load requirements of a typical remote village Rawdhat Bin Habbas (RBH) with annual electrical energy demand of 15,943 MWh. Rafha is located near RBH. The monthly average wind speeds range from 2.99 m/s to 4.84 m/s at 10 m height. The monthly average daily global solar radiation ranges from 3.04 to 7.3 kWh/sq.m. The hybrid systems simulated consist of different combinations of 600 kW wind machines, PV panels, supplemented by diesel generators. National Renewable Energy Laboratory's (NREL) Hybrid Optimization Model for Electric Renewables (HOMER) software has been used to perform the techno-economic study. The simulation results indicate that for a hybrid system comprising of 1.2 MW wind farm capacity (two 600 kW units, 50 m hub-height) and 1.2 MW of PV capacity together with 4.5 MW diesel system (three 1.5 MW units), the renewable energy fraction with 0% annual capacity shortage is 24% (10% wind + 14% PV). The cost of generating energy (COE) from this hybrid wind-PV-diesel system has been found to be 0.118 $/kWh (assuming diesel fuel price of 0.1$/l). The study exhibits that for a given hybrid configuration, the number of operational hours of diesel generators decreases with increase in wind farm and PV capacity. Attention has also been focused on wind/PV penetration, unmet load, excess electricity generation, percentage of fuel savings and reduction in carbon emissions (relative to diesel-only situation) of different hybrid systems, cost breakdown of wind-PV-diesel systems, COE of different hybrid systems, etc.