If the Polar Vortex happened today, Vermont and surrounding areas would not weather it, the way they did in 2014.   The Vermont Yankee nuclear plant has since shut down (for no non-political reason, still safe, up-to-date, excellent operational record) and that is 600 MW of reliable, dispatchable generation that is no longer available.   There is also inadequate natural gas pipeline-age in that region, and during events such as the Polar Vortex, gas will go preferentially to home heating, meaning there won't be enough for electricity generation.  It is not practical to store a supply of gas on site.   It must come in as needed by pipeline.

So Vermont's back-up plan, brought on by environmentalists who hounded Vermont Yankee to death, is for gas plants in the region to burn dirty petroleum, which can be stored in tanks on site (also risking toxic spills).  Most gas plants have dual burners which can burn gas or oil, but oil has not been used since the 70s, until now.