Pellet Stoves Inserts - Convert Your Drafty Fireplace Into an Efficient Heating Source Pellet stoves are either free-standing heat sources or fireplace inserts that fit into your existing fireplace. They can be highly efficient and can burn compressed pellets made from wood byproducts like sawdust. They are also considered "green" https://www.fireplacesandstove.com/products/us-stove-5040-compact-pellet-stove