... so-called "green/cleantech" I can say unreservedly it was about 99% hype and 1% reality. They dropped at least $2B in their attempt to diversify their portfolio into greentech and acquired a number of companies - including the one I worked for - to buy their credibility in the solar panel marketplace.
As it turned out, said marketplace - and greentech in general - was and is a bust. Rich yuppies are basically the only ones that can afford to purchase, install, and maintain solar panels even with massive State and Federal government subsidies both in the U.S., Europe, and elsewhere. Given the very poor efficiency of solar panels and their very long term ROI, those yuppies are the only ones with more money than good sense.
For all Al Gore's, the UN, and pro-globalists' hand-wringing over AGW (and I'm not here to get into THAT debate), the reality is that most people and therefore most businesses aren't particularly concerned about climate change. When the economy tanked in the 2008-ish time frame, the corporation I worked for - the world's largest semiconductor equipment company - said they had, in their 30+ years in business, NEVER see demand drop off a cliff the way it did. Consumer demand for electronic gadgets quite literally disappeared and did so almost overnight. It was a stunning hit to the solar plexus of that industry. Needless to say, a year on I was laid off.
Greentech far from saved them - and, thankfully, at least it was mostly THEIR OWN dollars they spent on greentech investments -- and it turns out the vast majority of the dollars they dumped into those investments turned out to be giant loss. It was nearly all hype and very little reality.
On a mundane level I don't have a huge problem with the Federal government taking big bets on cutting-edge technology that private industry typically can't afford. Note: NASA, the Military in general (from whom we have GPS among many other military-to-private sector innovations to thank for), and of course DARPA from whom we may not have this little thing called the Internet.
Even if there was no real skepticism around climate change I don't believe it would matter. The money the UN wants from the major nations to "fix" climate change would end up being a giant slush fund for lavish UN diplomat expenses. I'd bet big money not a dime would go to any good or positive net effect to supposedly fix or even seriously address climate change issues beyond expensive committees filing expensive 500-page reports and jet-setting between Dubai and New York and London and Tokyo to confab with like-minded global elitists. Climate change isn't something that will be fixed on a macro scale. That, among many other reasons (i.e., the general massive corruption and ultimate pointlessness of the UN), is why so many nations are resisting funding this cluster. Many people are struggling to merely survive in this world - in fact, the vast majority of the global population is in that bind - and concern over how many hydrocarbons they're pumping into the environment is of zero to less-than-zero concern.