Fossil fuels are very important fuel for electricity generation. These fuels are limited in availability and produce emissions that are hazardous to the environment, hence, their usage are required to be minimized. The power system analysis that minimizes the consumption of fossil fuels by generating units in a power system is termed Generation Dispatch. This is a power system planning problem that need to be solved accurately considering different factors and constraints. The Nigerian power system was deregulated more than a decade and half ago and a critical review of its Generation Dispatch Problem (GDP) solutions was carried out in this work. The review x-rayed the types of GDP, factors and/or constraints considered, and the optimization method employed for GDP solutions of Nigerian power system. Results of the review revealed that not much has been done and suggested research directions for work on the GDP of Nigerian power system.