retrofit pellet stove into fireplace?

[steve...]

I have a thousand square foot home and was averaging 6-7 days per bag last winter ($5.50/bag). It's a fairly mild climate here and I would typically run it for a few hours in the morning, then a few hours in the evening. The house seems to hold the heat pretty well. The guy who serviced my stove said the newer ones are more efficient than older ones like mine. I also use an electric heater in my bedroom - the thermostat is set low, so it only comes on when the house cools down at night.