Good for short stint to gain industry-experience, bad for long-term career
Pros
As an engineer, if you land in the right department, you can earn a lot of responsibility very early in your career (largely dependent on direct manager/supervisor). If you're the type to sit back, relax, and set your career on cruise control, you can do so here. Annual bonus is pretty generous, but mostly contingent on organizational performance. Most staff-level employees do not have to work more than 40 hours/week, so work/life balance is great. Meaningful work can be found, but only within a few small groups (most work is rudimentary and uninspiring).
Cons
Internal politics are substantial part of promotional opportunities (FAR from a meritocracy, but utilities can afford not to be one). Innovation is pushed heavily, but it's primarily superficial because true creativity and entrepreneurship is inhibited within a monopoly, both by culture and regulation. Pay is relatively low for engineers. Year-to-year raises barely beat inflation, and promotional raises are typically 5% or less; payscales are same for engineers in Washington, DC and Newark, DE, which means former are struggling and latter are living like kings. Meaningful feedback on performance is very few and far between; annual performance reviews are a joke and utilize a forced-quota rating system. Middle managers often hog the interesting work for themselves, effectively shielding their staff-level, direct-reports from meaningful work. Career development is very weak (this is common across the utility industry).