- Cowlitz PUD

Most of these inputs are straightforward values with defined parameters. Somewere modeled differently due to the uncertainty of the input. For loadrepresentations, stochastic representations were developed. The larger darkblue rectangles represent aggregate factors.The orange diamond represents a “decision” in the process. In this diagram the“Acceptable Plant Types” has this designation. Since only certain plant typeswere viewed as a viable alternative for the District, the field of possiblegeneration resources had been limited by some other work performed before thisanalysis. The model selects the “best” among the limited feasible possibilitiesoutlined later on.The last symbol, the green hexagon, represents the objective in the analysis.For this analysis, the objective is to minimize expected District power cost at anacceptable level of risk.16