The UK's grid controller is understood to be concerned that Scotland could struggle to keep the lights on during a transition period of about 18 months starting next March, when SSE will cut capacity at Peterhead from 1180MW to 400MW.
As previously reported in these pages, Peterhead will not be able to run at its new capacity until SSE has completed a £15 million upgrade scheduled to finish in autumn 2015.
If it wants to run the station in the meantime it would have to buy permits to operate at higher capacity from National Grid (NG), which is only likely to be economical for the company during periods of peak UK electricity demand, when power prices reach their highest point.
Outside these times, it is understood that NG is concerned there could be periods when having Peterhead offline could still mean that there is not enough power for Scotland. This follows the closure of Cockenzie power station in East Lothian earlier this year.
Some of NG's concerns are said to relate to the fact that a series of network upgrades currently taking place have made the system less flexible than usual.
But the operator also foresees a situation where demand could sometimes exceed supply because there is either not enough wind to power Scotland's wind turbines or too little rainfall for hydroelectricity.
If Peterhead is offline, Scotland would have around 4.8GW of capacity from thermal and nuclear power, plus around 1.3GW from hydro and 4.5GW of wind power. Peak demand is around 6GW.
The move is part of a package of wider efforts that NG is undertaking in the face of capacity concerns around the UK.
Earlier this month the grid controller announced that it may ask businesses to cut power consumption next winter between 4pm and 8pm at an expected cost to consumers of over £20m.
It has also made clear that it will pay generation companies to bring mothballed plants online to cope with peak demand.
A spokeswoman for NG said: "Discussions we have with all of our customers are confidential."
SSE declined to comment.