The Hourly Electric Grid Monitor is EIA’s live dashboard for the U.S. electric system. It publishes hourly demand, demand forecast, net generation broken out by energy source, and interchange between regions, for the lower 48 as a whole and for each individual balancing authority. Data is downloadable.
How it gets used on a real project
For anyone learning energy markets, this is the fastest way to replace abstraction with observation. You can watch the duck curve form in CAISO on a spring afternoon, see what a heat wave does to ERCOT demand, or look at how much solar a region is actually producing at 6pm versus noon. Those shapes are the whole reason storage attach rates, PPA structures, and curtailment risk look the way they do.
Practically, it is also a quick reality check on a merchant revenue assumption. If a model implies a generation profile that does not resemble what the balancing authority actually sees, that is worth investigating before the assumption reaches an investment committee.