Biomass-fired power plant projects are usually developed with high risk in comparison to the conventional fossil power plant, merely because of the uncertainty of long-term fuel supply and cost. The project development is traditionally carried out by initially assuming the fuel cost followed by detailed engineering design, project cost estimation and economic analysis. This paper presents an alternative way of project development by finding the maximum affordable fuel cost to settle the fuel purchasing agreement before commencing the engineering part of the project development. Mathematical models of fuel cost incorporating various fuel parameters and power plant operating parameters are developed. The maximum affordable fuel cost was found to depend on the fuel moisture content, area-base annual availability, the required financial return, size of the power plant, and the operation of the power plant. Maximum affordable fuel cost is sensitive to the specific investment cost, change of electricity export factor, fuel moisture content, price of electrical energy, equipment efficiencies and annual operating time.