The seven-minute power outage is significant enough that it causes the community to come together and discuss what to do going forward about the increasing lack of power. However, the lack of actual effort toward finding a permanent solution makes the people of Ember angry—that's the change that occurs after the power outage.
Power outages are a fact of life in Ember, but when one lasts for seven minutes, it's not business-as-usual. It's twice as long as any outage that came before and puts people in a silent panic. Unlike the past outages where people would talk about the time without power, no one seems inclined to discuss the seven-minute outage. DuPrau writes:
It was strange how people didn’t talk much...
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