How many homes in the US use wood pellets for heat?

“According to the Pellet Fuels Institute, approximately 1 million pellet stoves and fireplace inserts are used in homes throughout the U.S. and Canada.”

Biomass magazine

Wood pellets are expensive. only a guess here that maybe people that live out in the country would use pellets for their main source of heat. marinelife has stats that may interest you.

Just for the record many people that “live out in the country” use wood that we get for free or at very low cost. An ice storm is our friend.
I know one guy with a pellet stove and he complains of the noise from the fire box blower, air circulator, and auger. When the power goes out the stove turns off immediately . Not useful in an emercgency