Thieves tried to steal copper cable from a generator being used to provide emergency power.
Police said the thieves attempted to steal the cable from a generator at Tesco Metro on Heysham Road on Thursday night.
A spokesman for Morecambe area police said: “The last week has seen some great people going out of their way to help others.
“Then we find out someone had a go at stealing copper cable from the generator at Tescos on Heysham Road.
“Not only is this sad but you run the risk of being fried. If you see anyone lurking round any of the generators, call police on 101.”
Up to 80 generators are being used in the region since Storm Desmond flooded the main electricity substation on Caton Road in Lancaster, cutting power to 55,000 homes in the area.
Electricity North West are working to get 23,000 people back to the power grid between 5pm and midnight on Friday.