TFZ researchers recommend optimizations for pellet stoves and wood pellets

Scientists from the Technology and Promotion Center (TFZ) have identified key methods to reduce carbon monoxide and dust emissions in pellet stoves. Through the FuturePelletSpec 2 project, researchers tested commercial devices alongside a specially developed prototype designed to operate well below current emission limits.

The study found that emissions are significantly lower when stoves utilize automatic fuel regulation and optimized burner pot designs. Automatic regulation stabilizes combustion by controlling the amount of pellets entering the combustion chamber, whereas optimized burner pots better distribute air supply and recirculate exhaust gases.

Regarding fuel quality, researchers identified potassium content, the silicon-to-potassium ratio, and pellet length as critical factors. To ensure low-emission operation, the project recommends wood pellets with an ash content of up to 0.5 percent mass, a water content of 5 to 10 percent, and limiting the proportion of very short pellets (under 10 millimeters) to prevent incomplete combustion.