WOW, talk about price gouging! I don't know how they are able to get away with that!! So you are absolutely right about going with Propane...Buy it in the off season and be prepared. I always say, if you have a spare part on the shelf, you'll never need it!
I really don't trust the grid at all! I actually heat my house with Anthracite Rice Coal. All digital controlled and keeps inside the house temp within 1°, no matter how cold out. I buy the bagged coal in the summer and store it until I start heating in the fall. A single pound of this stuff puts out 14,000btu. And its cheaper than anything else you can heat with. I have a battery backup that will run the furnace for up to 8 hrs if I'm away from the house. And a small 1700w sine wave gen that will run the furnace at idle on less than 2 gallons of gas a day. I keep about 50 gallons gas on hand and put it in my mower in the summer if I don't use it in the winter. So I'm not out anything really. This 'ol boy is not going to freeze!
It never hurts to be prepared in more than one way....Just when you think you've got everything under control, Mother Nature smacks you right upside the head!