Demand charges are based on peak power demand; how can solar+storage mitigate them?

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Demand charges are determined by the highest instantaneous power drawn from the grid during the billing period. Solar plus storage mitigates them by peak shaving: the storage system charges when demand is low or solar is abundant and then discharges during the hours when the facility would otherwise push the grid meter to its peak. By supplying part of the building’s load with stored energy (and solar energy during daytime), the actual grid import at the peak moment is reduced. That lower peak is what the utility uses to calculate the demand charge, so the bill drops accordingly.

In other words, the goal isn’t simply using more energy during the day, but keeping the maximum power draw from the grid as low as possible. Exporting energy to the grid can affect net consumption, but it doesn’t reliably guarantee a lower measured peak the way active peak shaving with storage does. Reducing system voltage isn’t how demand charges are managed.