Some Australian states are discovering what happens when they have too much rooftop solar

Alerts to possible power shortfalls have become a familiar occurrence. But experts say it won’t be long before the opposite is common

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When Victoria basks in mostly sunny spring weather this weekend, energy authorities will be monitoring how far electricity demand ebbs. If needed, they’ll turn off rooftop solar systems to ensure stability for the grid.

Such minimum system load events, as they are called, have emerged as a new challenge as households across Australia take advantage of plunging prices for solar panels to shield themselves from rising power bills and cut carbon emissions.