Traeger Alder Pellets20 lb. bagQ: “HOW LONG WILL A TWENTY (20) POUND BAG OF BARBECUE PELLETS LAST?” A: On HIGH, the grill uses 2 pounds of pellets per hour, ($2.00 per hour). On MEDIUM the grill uses 1 pound per hour, ($1.00 per hour).On SMOKE the grill uses one-half pound per hour, (.50 cents per hour). Consumption will vary with weather conditions. Cost based on 20 lb. bag of pellets at $19.99.Do not use pellets for pellet heaters, these pellets are not “Food” grade and may impart undesirable flavours and may not burn properly.