A storm this weekend knocked out power to millions of buildings in US. The utilities that serve the affected areas say it might take until midnight on Friday, July 6, before everyone gets back online. July 6? Are you kidding? Why does it take so long?
First off, it's important to remember that a lot of buildings need power more urgently than our homes. When repairing a major outage, the crews first address problems at the supply lines that serve hospitals, water filtration plants, and fire or police stations. If your home happens to be along one of those substation's lines, then you may have power quickly -- if not, you'll wait in the dark.
The nervous system metaphor is an accurate way to describe what goes on during repairs. To loosely chart the backbone comparison, a utility's power station is like a brain, its substations are the individual vertebra, and the power lines trail outward like nerves through transformers, where the voltage is stepped down for use in individual homes.
The types of customers that may wait longer are the more isolated buildings -- the ones who would be at the fingertips or the extremities -- of the electrical nervous system. For a rural development, an entire street or subdivision could be served by a few critical transformers. The complex work to fix downed power lines -- clearing a tree, replacing a pole, repairing a transformer -- will typically take place in areas serving thousands of homes before the utility dedicates those resources to the lines that only serve a few hundred. The first action is the one that brings the greatest happiness to the greatest numbers.
Customers who have sweated through long outages in the past might know they're vulnerable have generators standing by. Great! But be careful. Here are a few words of generator safety from one of the great experts on the topic, Popular Mechanics' Roy Berendsohn: Plug the generator into a transfer switch wired directly to the house's breaker panel -- not a wall outlet. To ground a generator, either run a wire from the machine's grounding screw to the grounding bus bar on the service panel or just stick it in the ground (check your particular model's instructions). And don't run the thing indoors or in the garage -- even if it's raining.