Techno-Economic Viability of Tidal Power Generation in the Bight of Benin, Nigerian Coast

Abstract

Despite its prodigious endowment with ocean renewable energy resources, Nigeria, especially the Southwest industrial hub, suffers massive power problem, leading to numerous socioeconomic and security problems such as high poverty rate, unemployment, collapse of the manufacturing sector, difficulty in doing business, falling human development index, and so on.  Over 65% of the population of Southwest Nigeria are residents of the three. Given that about 70% of Southwest Nigeria’s population and the nation’s industrial hub is concentrated in the coastal states of Lagos, Ogun, and Ondo, with a total of 273Km shoreline, it is imperative to explore and harness ocean renewable energy sources such as tidal energy conversion for mini-grid electrification.  A 21-year tidal energy data of the Bight of Benin between 2000 and 2021 was acquired and analysed with a hypothetical 100kW tidal-powered mini-grid in hybrid configuration. The systems were simulated and evaluated with HOMER, Matlab Simulink, Techno-Economic Levelized Cost of Energy (TELCOE), and generic Cost of Energy (COE) computation. Finally, the Techno-Economic Renewable Energy Viability Index (TEREVI) was applied as a confirmatory determinant energy model. Tidal power generation technology has a TEREVI score of 0.65, which is well below the proven threshold due to the relatively low tidal range in the 2 to 4 sea storm class; thus, the recorded mean tidal range is 1.1m with periodic and seasonal spikes which follow quite a similar pattern as the windspeed and wave energy variations. Tables 4.3 and 4.4 show information on the tidal heights and power potentials in the Bay of Benin.  The cost of generating electricity is also very high at $0.096153237/kWh from HOMER optimization results,   $0.091201/kWh for Matlab simulation results, $0.062248695/kWh for LOCE, and $0.07019/kWh for TELCOE, which makes it uncompetitive at current market rates except for long-term research and development purposes. The low tidal range at the Bight of Benin, coupled with the technological infancy of tidal energy, makes it non – commercially feasible and below the TEREVI threshold.