While most in the process sector have welcomed the UK government's belated backing for shale gas, some engineers now see a need to manage expectations of some of the more enthusiastic converts.

For example, in a recent letter to The Times, London mayor Boris Johnson promised to ‘leave no stone unturned or unfracked’ if shale gas is found in London.

In a statement on his company's website, though, David Symons, director at consultancy WSP – a firm with significant international shale experience – responded by suggesting that Johnson was getting a bit carried away:

"Although oil has been found in many areas across southern England – from the Weald basin to even some small finds in north London - the reality is that shale gas is a new science and there’s still considerably uncertainty on where the resources are and whether they are economically viable to extract, " said Symons.

“Rather than big sweeping statements the Mayor could do much better to focus on the elements in the 2020 Vision that are in his control, such as making London a leader in energy efficiency." 

Fair comment, I suppose, but the Mayor's robust stand does make a welcome departure from the unfounded scare stories about shale, which are still being peddled by many politicians, scientists and journalists.