Many professional hosters have certifications, but the problem with that is usually that in a mostly fossil electricity grid, buying up some renewable capacity doesn't really change much even if technically you can claim to run on 100% renewable energy.

For my private system I'll probably put up a public Grafana dashboard at some point that will show the amount of electricity produced and the battery charge status. But I will have a few other things connected to it, not only the servers running slrpnk.net