There you are driving along with all the family and the presents when you realise you are low on fuel. Then you remember that by taking the scenic route you have avoided all the petrol stations. A nice day out has just gone badly wrong.
There is a problem with our hopes that fracking will fill up the tanks, not only in vehicles but in the economy when the other supplies of oil are reduced and increased in price.
Moreover, it is a UK problem that is tectonic, meaning allegedly the wrong kind of rocks in the wrong place for us to take advantage of what may be down there. It seems that other places are not the same and we may have been taking our geology for granted.
The upshot is that a lot of drilling will have to be done to determine whether or not fracking drilling can work. Our politicians may find it challenging when explaining this to their constituents.
So how long have we got?