His conclusion is that we could run out of natural gas in a decade, especially if we make a mass transition to it as a source of electricity and transportation fuel. (Our proven reserves, as opposed to our potential or likely ones, are only good for a decade’s worth of energy.) Or we could run out in 100 years, which is the supply all the industry-fluffing hacks at the Wall Street Journal insist we have. We simply don't know.
Nelder’s article provides some eye-opening insight into just how much the industry hypes the size of potential gas reserves. But his larger point is that with this much uncertainty, we are taking a huge risk in thinking that natural gas is anything other than a temporary solution to our energy woes.
I suppose I don't need to remind you that sources of renewable energy aren't projected to peter out for billions of years.