So the short answer is 'mostly dependent on area', that a higher lifestyle is subject to fewer / no utility issues, as Sphinx says.
The question could be raised, 'well, what about places that have everything from Medium to Luxury++ lifestyles in them?' My answer is 'prioritization'. You pay a ton of money every month, you get priority to whatever power exists. In general the grid in whatever city within which you hang your hat is going to have power generally sufficient for the people who live there, just like today; theoretically, with their extensive use of nuclear power as well as green technologies, they may technically be more power-sufficient for their population - GridGuide power transmission (not to mention traffic control) for electric vehicles, remember? But there are constant assaults, at one point or another, on the grid infrastructure. That might be a high-speed t-bird chase slamming into a high-voltage power transmission tower, taking down the entire structure and the lines connected to it, requiring the system to re-route the power; it may be like Dyslexic says, Yet Another Illegal Hook-Up, to power a house, or an apartment complex, or an illegal medical facility, and the tap screws with the grid itself in that area.
Sphinx again gives a great rundown of the local power-generation things; I'd suggest that Gaeatronics is trying to tap tidal power in and out of the Sound, maybe in the Straight of Juan de Fuca. But last I knew, most nuclear power plants are not servicing just one arcology; AFAIK, the Seattle Aztechnology pyramid buys power from Gaeatronics. Four nuclear power plants operating, plus various extras, create a HUGE amount of power, so should feed not only Seattle but people for tens, even hundreds of miles around - all of the SSC, I'd say, as well as possibly some of the other nearby nations. So _availability_ of power really isn't an issue.
The grid, however, whether that's locally (blow a couple of lines, whether overhead or underground, kill a sub-station) or Seattle-wide (get into the servers with a virus - see 'Brainscan' for the execution of just that), can be mucked with. It might be a very difficult target, just because, but it's certainly run-worthy - especially since it's likely to be a setup / trigger for some OTHER shadow-action.