Making pellets out of sawdust... why don't more lumber mill companies do this?

[SwampDonkey]

Standard chimney where I live is 3 feet above the peek of the roof. Too short and you loose draft and you get back draft and a smoky room. Pellet stove chimneys are smaller than firewood chimneys around here and none are above the peek of the roof that I've ever seen. One fellow had a down draft problem and his hopper of pellets in the stove burnt up, not in the burn chamber. Almost had a house fire. I suspect an improper install. I don't know of anyone else who has had the issue.

[Evgenii.B]

Pellet stove chimneys are smaller than firewood chimneys around here and none are above the peek of the roof that I've ever seen.

That's absolutely true for pellet stoves equipped with control panels and blowers. They're as convenient as gas boilers, programmable based on weather conditions or set schedules. They automatically increase pellet feed and blowing, so they don't require strong chimney draft. Typically, these stoves come with batteries that allow them to operate during power outages. If the battery malfunctions, the fans stop, the temperature drops, and the draft disappears, which can lead to a fire.
I mentioned the increased chimney draft in cases where a passive pellet burner is installed on wood or coal boilers. It doesn't have fans or a controller. Its hopper seals tightly, so there's no smoldering of pellets when it goes out. Here's an example of such a retrofit in the photo.