Pellet Stoves Inserts - Convert Your Drafty Fireplace Into an Efficient Heating Source Pellet stoves can be free-standing heat sources, or fireplace inserts that fit in your existing fireplace. They burn compressed pellets made from wood byproducts such as sawdust and can be highly efficient. They are also "green" since https://www.fireplacesandstove.com/categories/pellet-stoves/2