Iwas cheered up by an unusual sight recently. Scanning the carnage of the last few weeks on global equity markets, I noticed two US stocks doing a very strange thing – rising in value. I had to laugh, as both were what I’ve always regarded as “green” basket cases – a fuel-cell outfit and a “next generation battery” technology company.

But their peculiar behaviour hints at a bigger story. In theory, the wheels were supposed to come off the great green bandwagon as oil prices fell and investors ran away from “high risk” stocks. Instead, however, the green sector has proved a little more resilient.