The return of winter weather, combined with an unexpected reduction in electricity generation, prompted a surprise grid alert by the Alberta Energy System Operator Tuesday morning.
Notice of the alert was posted on the AESO website at 7:15 a.m. and ended at 8:22 a.m.
AESO spokesperson Diane Kossman said “through tools such as voluntary curtailment programs, participants were asked to reduce their energy use.”
“There was no need to issue a public alert (asking the public to limit electricity use),” Kossman said, because “there was still a comfortable supply cushion and we knew we’d be coming back out of the grid alert pretty quickly.”
However, some of AESO’s industrial users reposted notice of the alert on social media.
Asked why the grid alert was needed, Kossman said the temperatures Tuesday morning were “the coldest we’ve had and there were three large generators that were offline.”
Kossman wouldn’t say why the generators were offline but says it was expected.
She says the production of wind energy was also “lower than it was expected to be.”
On its website, AESO says a grid alert is issued “when the power system is under stress and we’re preparing to use emergency reserves to meet demand and maintain system reliability. Consumers are asked to reduce their electricity use during Grid Alerts to help mitigate the possibility of undertaking more serious emergency measures to balance the system, including rotating power outages.”