Let's say it did consider how the houses are cooled or heated... It would, maybe, make a difference of about "half a planet".

This is not just about individual choices, it's about collective choices. Regarding public transportation and urban sprawl, for example. Of course some people live in places where there is no public transportation: over the past century all we've done in North America is encourage urban sprawl, individual housing construction, more roads and more cars. That's what our economy eats for fuel.

Reversing those trends will feel like a significant sacrifice to many, and I think most won't make it, at least not in this generation, not until forced by, say, penury of fuel for their cars. It would also need a revolution in urban planning, not one city at a time, but with all cities working together. Some cities are making progress by at least noticing the problem. But to tell you the truth, I'm not holding my breath...