Ten corporations, including BP, Shell and Microsoft, are setting up a climate tech accelerator to channel more funding to sustainability startups, which often struggle to raise investment. According to Jon Creyts from the Rocky Mountain Institute, the US-based environmentalist think-tank that will lead the accelerator, investors are so put off funding climate change tech that there's only been one hard tech company in the last decade to secure enough funding to be successful.

I believe that solar energy will enhance the returns of existing Real Estate Investment Trusts (REITs) and also create a whole new class of REITs. The limited number of deals that we have seen so far is just the trickle before the floodgates open.

Cryptocurrency is not an obvious candidate to cut greenhouse gas emissions. Just mining bitcoin, the primary blockchain-based cryptocurrency, emits about 22 megatons of carbon per year (the precise number is hard to pin down). But Apple's co-founder Steve Wozniak is backing a new cryptocurrency promising to do just that.