I heated my old house with a pellet stove. Takes the electricity of a 60w light bulb, to run the feed augers and the 2 blowers (one for combustion air, one for heat into the room). To heat my HOUSE, I would go through about 2T of pellets a season (50-40# bags). I'd get them by the ton (on a pallet, it would squat my Ram 2500 about 1.5") at the local Southern States for a good price. Make sure to get LOW ASH pellets.
Trust me.
Loved it.
Outside air intake for combustion (2.5" PVC pipe through a hole in the wall, wrapped with insulation); 4" double-wall, 0"-clearance-to-drywall chimney. Mine had the ability to hook to a normal thermostat, which I had upstairs (split foyer house, stove was in the finished basement), and it worked like a champ. Keep the hopper full and you have heat. Twice a month I'd let it burn out so I could de-ash the burn pit (shop vac if COLD, or just a garden trowel if still warm and I needed to fire it back up fast). They have them now that are dual-fuel and will also burn corn. Not sure about efficiency on those...but it could be an option depending on your region and market availability.
Over the years (I used it for nearly 20 years) I started keeping a spare blower motor on a shelf, just in case, and if I used it I'd order another immediately. Ditto the auger motor (which I'm not sure if I ever replaced, just kept one on hand "in case"). Other than occasional motor replacements (like, maybe once every 3 years or so - remember, this was my sole heat source in the HOUSE), it was a great system. Had a cleanout on the chimney outside, and a brush-on-a-stick, to de-ash every month or so....and that was it.
On "low" heat...it would burn for 3 days on a single 40# bag, and keep the house above 50 degrees.
Great system if you have a dry place to keep a ton of pellets. If they get wet, you now have a solid 40# brick of sawdust and glue - just like a wet bag of sakrete. Keep them dry! I had a covered patio just ouside the basement entrance - 15' from a parking (unload) space, and 20' from the stove inside.