Pros
Good benefits, jobs security, flexible work schedule if you have commitments outside of normal work hours. Some people at the Company are really smart and good at what they do. Lots of teams in the Company are doing really interesting work.
Cons
Depending on what team you are on you can either have a great work life balance or a very poor work life balance. I've rarely worked a 40 hour work week for the past two years (supposedly a benefit of working at a utility) and have worked numerous weekends. It takes months and months to hire someone even after your team gets approval. While there are some people at the Company who do great work there are many people who have been here years or decades that just do the bare minimum to get by. The bonus structure also does not really motivate high performers (In a "typical" year low performs would still get a total of a 7.5% bonus in my position, and high performers typically get up to 12.5%) not exactly a big range between those doing the least an those doing the most. Many people often rarely make deadlines as well with no consequences. This comes back to the Company's inability to hire people in a timely manner. There are seemingly never any severe consequences for not performing and meeting deadlines (besides perhaps being held back from a promotion or having a slightly lower pay increase than coworkers). Management also seems to feel the need to a restructuring at least every two years.