Hydrodynamic Performance Evaluation, Operational Efficiency, and Levelized Cost of Electricity Analysis of a 600 MW Hydropower Plant: A Case Study of Shiroro Hydroelectric Power Station

Abstract

Reliable grid supply remains a binding constraint on industrial growth in Nigeria, and large hydropower is the most mature renewable option on the national system. This study evaluates the hydrodynamic performance and levelized cost of electricity (LCOE) of the 600 MW Shiroro hydroelectric station (units 411G1–411G4) using plant operating records from January 2010 to December 2020. Shaft power, overall, first-law efficiency, generation shortfall, power delivery ratio, capacity factor, and LCOE were computed from the governing hydrodynamic and cost identities and checked in MATLAB. Mean shaft power was 507.99 MW (84.73% of installed capacity), mean overall efficiency was 88.21%, and the mean capacity factor was 46.04%. Calculated and logged generation differed by only 0.42 MW on average. The period LCOE was ₦63.47/kWh. Yearly unit costs plotted against selected thermal plants are not on the same cost basis: the thermal traces are short-run, fuel-dominated generating costs, whereas the Shiroro series includes present-worth capital recovery and zero fuel. Sensitivity of the period LCOE to capacity factor and real discount rate is reported. Outage cost is estimated separately from LCOE and is not included in the LCOE numerator. The conversion process is hydrodynamically stable; energy adequacy is limited by seasonal storage rather than by machine efficiency. Component-level exergy destruction in the penstock, turbine and generator could not be quantified from the available logs and is identified as future work.