The ultimate solution (that is rarely mentioned) is less people on the earth.
We all want more, so our economies have to grow and produce more. We have to fight poverty in the 3rd world. So they will also start to consume more.
Nobody wants to step back, as long as others aren't either ("Why should I live in a cold house, when those big shops downtown leave their warm store open?"). And don't forget the extreme pollution caused by the production of our meat. But does that make me a vegetarian? No.
And how about those cars? Everybody wants to drive a comfortable, big car. It's only because high taxes on cars and fuel that we (Europeans) drive smaller cars, but deep down, that's involuntary. And how about all those highways, filled with cars with only one person in it? Isn't that a weird sight?
And all those big office buildings, keeping the lights on 'till late at night, even though nobody's present? Because it looks 'nice'.
I am no saint and don't want to judge other people, but I just want to point out that WE are the problems (as consumers) and cannot put all blame on governments and big corporate companies. It's the egoistic, selfish part in every human being that wants more and more. Governments now have to come up with rules that force us (consumers and companies) to consume less and produce environment-friendlier.