This isn't exactly what you're talking about, but I keep waiting for Google's Chrome team to add an energy rating icon to the browser that gives you a rough fee

This isn't exactly what you're talking about, but I keep waiting for Google's Chrome team to add an energy rating icon to the browser that gives you a rough feel for how energy intensive a given page is. At some point the shaming would begin, web devs would respond, and then I'd generally get what I'm really after -- much faster page load times!