PJM has online training courses. Taking "PJM 101" is worth it to get a sense of how the market system and the actual operation interact. A few hours and you know more about the power grid than 99% of the population, but less than any PJM employee or energy trader.
One of my interests is how market-based systems fail. They're feedback systems with delays. Some of the delays are short; others are measured in years. A point I make regularly is that such systems have no guarantee of stability. In short-term energy markets, the consequences of this are immediate, because there is not much inventory in electricity.
