A technique of implementing performance monitoring in a power plant is appropriate to control operating parameters and factors connected with the efficiency of the energy production process in an energy marketplace that is more complex than in the past, and that takes variable costs besides the cost of fuel into account, e.g., environmental credits, equipment degradation and repair costs, electrical energy trade market factors like ramp rate, LMP (Locational Marginal Pricing) factors, the ability to deliver contracted power levels and spot transactions, etc. The technique applies a statistical analysis to collected power plant data to determine the factors that are best controlled or changed to affect (increase) the efficiency or other primary performance indication of the plant, as well as to establish baseline or best-possible operational constraints to be used to control the plant in the future.