What I would add is that if you look at the history of the energy sector, or of any manufacturing sector, really, what was often driving what today we would call green behaviour was simply bottom-line considerations.
What is pollution? Well, pollution is waste that is made from inputs that you've paid for, and the stuff is there, and it's in large quantities. It's all the same thing. Whether you look at the history of Standard Oil, or at any manufacturing sector, or at what we've heard today about natural gas, waste is not lucrative. If you have the stuff and you can turn a problem into an opportunity and improve your bottom line, that is still, I believe, the main driver of greater efficiency and greener behaviour in business. In one of my papers, I document that this has been going on for a century and a half in the oil business.