In the microbial production of useful products, it is important to understand the allocation of substrate energy for maintanance, growth, and product formation. Methods are presented to obtain point and 95% confidence interval estimates for the true growth yield parameter, true product yield parameter, and the maintenance parameter. Methods are presented which allow all data to be used simultaneously for those cases where more than the minimum number of measurements are made at each specific growth rate (or dilution rate). Three estimation methods and two forms of the energy allocation equations are investigated. Point estimates are similar for the three methods, but interval estimates are considerably larger for one of the three methods. The results depend on the form of the equations.