I’m curious what they will use as a data source for this. I regularly consult the Electricity Maps App (mostly for personal curiosity but also for timing EV charging) but I’m curious if there are other data sources available. Timing will be vastly different depending on where you live. Where I am in PJM Interconnect territory, overnight is usually best as demand is lower and nuclear makes up a greater share of grid generation. But in California the cleanest times are mid-day (lots of solar) and overnight is far worse from a climate perspective.