from same article:Q: Is 'the business of green' a bubble?
A: "No. For political reasons the United States has been behind others on green issues, but once it catches up it will be a domino effect. In 20 years they won't talk about regular roofing because it just won't exist ... there is so much rooftop real estate that is completely under-utilized.
A: "No. It's become quite obvious we do something now or it will be an irreversible trend with catastrophic consequences.
"The only chance of it being a bubble is if we lack the political commitment to drive emission reductions worldwide -- and if we do that we might as well forget about any environmental effort whatsoever because climate change is hitting us hard and the trend is likely to accelerate. I think it's very unlikely political support will go away.""