From the article: "Every 2 hours, GreenForecast.au servers grab data from AEMO, a weather forecast and two other minor sources"
I'm no expert in US energy... Presumably each of your (many) markets will have different available data, but more-or-less equivalent. Probably do-able, but will need to be re-done several times over!
[0] https://nemweb.com.au/Reports/Current/ [1] https://aemo.com.au/energy-systems/electricity/national-elec...