The phrase
"duck curve" refers to a graphical representation of electricity demand over time. It shows a downward sloping curve that looks like the shape of a duck, with a steep belly and a low neck. It is used to depict the challenges faced when renewable energy sources, like solar power, generate more electricity during the day than what is needed, creating excess energy. This excess energy can be difficult to manage and store, requiring adjustments in the power grid to handle the fluctuations in supply and demand throughout the day.
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