A long term power market simulation (LTPMS) model to study alternative wholesale power market structures is discussed. LTPMS is a prototype that uses Microsoft Excel software in the form of integrated worksheets for the grid operators, independent power producers (IPP), electricity customers, and power authorities. It models the generating capacities in the categories of hydro, nuclear, coal, gas, oil and not as individual generating units. The use of LTPMS would be valuable for making comprehensive simulations and studies before critical decisions are made.