So there's a risk we run out of gas in five years? This was not a report to bury on budget day

Chris O'Shea, the chief executive of British Gas-owning Centrica, tells an eye-popping tale from his early career in the North Sea offshore industry. During a routine underwater inspection in the 1990s, an unexploded bomb from the second world war was discovered close to the pipeline carrying oil ashore from the large Nelson field.

- Nils Pratley

Happily, the danger was dealt with. The point of the story is only that risks to critical pieces of infrastructure can come from unexpected sources.

It is something to bear in mind when reading about the "emerging risk to gas supply security", as detailed in an assessment last week by the National Energy System Operator (Neso). This 50-page report was released on the afternoon of budget day. It was almost as if the government, or its in-house system operator, didn't want the central finding to make the front pages.

In short, Neso found there was an "emerging" risk of Britain running out of gas if an important piece of kit were to be out of action at a bad moment. It modelled five "pathways" for gas demand out to 2030 and 2035 and tested against a prolonged spell of very cold weather. Here is the key sentence: "In the unlikely event of the loss of the single largest piece of gas infrastructure, gas supply falls short of demand for all pathways in 2030-31."