The advice was not issued in response to a threat to the electricity supply.
Instead, it covered a wide range of eventualities, such as extreme weather, cyber-attacks and terrorism.
Grid operator Neso said it was confident electricity supplies would be secure this winter.
But Prof Helm questioned whether the network could cope with a prolonged spell of cold, dark and windless weather, known as a Dunkelflaute.
He said: “Right now there really are questions about whether the lights will stay on. Whether, in fact, the energy system we built, and particularly the electricity system we built, is capable of dealing with the kinds of shocks which result from the reliance on intermittent generation.”
He told his podcast, Helm Talks, that Neso had said: “Don’t worry, the lights will stay on this winter.”
Prof Helm, a former government energy adviser and the author of Climate Realism: Facing the Facts about Energy, said: “The clue is that the grid operator needs to tell us, don’t panic.
“And the Prime Minister needs to tell us, well, don’t panic but do prepare yourself for a serious interruption in supply. When I think about this, I ask myself, what’s new?”
