Most pellet stoves are incapable of burning ordinary wood for fuel. They are only able to burn pellets designed and approved for their use. Generally, pellets are 3/8 inch to 1 inch in size and made of compacted bark, wood chips, paper, agricultural crop waste, sawdust and other organic matter.
A few types of pellet stoves are capable of burning biomass fuels, including small wood chips, corn kernels, sunflowers, nutshells and dried cherry and peach pits. However, it is best to check an owners manual before introducing anything other than approved pellets into a pellet stove.
People who prefer pellet stoves say they like them because they operate more efficiently than most wood stoves. The stoves work by channeling pellets from a storage hopper into a burn pot by means of an electrical auger. The heat generated by burning the pellets travels through heat-exchanger tubes and a convection fan into the room in which the stove is located. A drawer located beneath the burn pot collects ash. However, very little ash accumulates compared to what is produced by a wood stove.
The average pellet stove is about twice as energy efficient as a wood stove, despite operating on electricity. Battery back-ups are available for most models, making them useful during power outages.