Is a wood stove or fireplace for you? Do you already have one in your home but don't know whether it would be cost-effective to use it? Some simple math can help you decide.
Look at your energy bill. How much do you pay for heat? Let's say last December you paid $310 for heat. Divide the number by the days in the month, in this case, 31, to get how much you pay for heat each day. In this case, it would be $10 per day.
How much would wood or pellets cost? Let's say you could get a chord of wood for $200. You could use the chord to heat your house for 50 days (depending on the type of wood and the type of fireplace, wood stove, etc). $200 divided by 50 equals $4. So you could heat the house for $4 a day for 50 days using a chord of wood.
This means you could save $6 per day on your heating costs by switching to wood for 50 days. $6 per day multiplied by 50 days equals $300. Nice.
Don't forget to account for the other costs associated with using a wood stove or fireplace: having it cleaned once a year or every other year (depending on how often you use it), buying tools to help stir the fire and clean the ash, and maybe some fire starters. Let's say this stuff costs you $100 per year. This means, using the wood stove, even just on weekends, can save $200 per year. If you're home on the weekends, and you already have a wood stove or fireplace, why not save a little money?