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9.4.2 System Implications of Intermittent Generators

Clean energy systems must deliver reliable electric power on demand. Intermittent generators (wind, solar, tides, waves) cannot stand alone. The rest of the system must provide power when the intermittent resource is unavailable. Therefore a system perspective is essential for assessing overall cost and performance. Classical systems architecture explains the relationship between intermittent generators and the rest of the system. Traditional concept development approach starts with simple concept models that point to hard constraints that remain valid in more complex systems. Additional variables are added to the model in stages to build more complex systems. This system perspective points to key features of electric power systems with intermittent generators and identifies new knowledge needs.