I've been reading a lot of posts regarding heat output for each type/brand of pellet out there and wanted to add my experience to the discussion.
I've been burning pellets for over 10 years and have noticed that the heat output of my stoves varies depending on what pellet is used (duh). I used to think this is just the difference in pellet brands, however recently I had some extra time on my hands and decided to test and see what difference there is in the brands that I have stored for this winter.
This year I had 4 tons of pellets delivered and stored for my 2 Bosca Spirit 500 stoves. 1 ton is Atlas Ultra Premium Red Fir, 1 ton is North Idaho Energy Premium and the other 2 are Westwood Premium (which are re-branded Okanagan Pellets from B.C.). All of these brands are softwood pellets and are considered the best available in our area.
Using a thermometer (procedure similar to one I saw on this forum) I tested each pellet in a clean stove one bag at a time. I tested heat, ash and time it took to burn the entire bag. I used the 3rd highest of the 4 settings on my stove for the test. Here's what I got:
Westwood Premium: 265° and 12hr 18 min burn time (second lowest ash no clinkers)
North Idaho Pellets: 252° and 13hr 53 min burn time (lowest ash by far no clinkers)
Atlas Ultra Premium: 248° and 13hr 22 min burn time (highest ash no clinkers)
The burn time of the Westwoods jumped out at me and made me burn a second bag to make sure I didn't make a mistake. The time for the second bag was within a few minutes of the first bag (the time above is the average of the two).
After looking at the pellets themselves I found out why the Westwoods were both the hottest and had the shortest burn time. The pellet length is very short compared to the other two brands. Also they are very consistent in length. The short and uniform length allows more consolidation both in the hopper and in the auger allowing a higher volume of pellets to fall into the burn pot per revolution of the auger. I further confirmed this when measured the "high water mark" in the hopper when loading a single bag of each brand. The hopper was almost 2" "more full" with the North Idaho and Atlas pellets than with the Westwoods.
So while there is definitely a heat output difference that is dependent on quality of material used, there seems to be a direct correlation to size of pellet as well........at least in my less than scientific test.
I've been burning pellets for over 10 years and have noticed that the heat output of my stoves varies depending on what pellet is used (duh). I used to think this is just the difference in pellet brands, however recently I had some extra time on my hands and decided to test and see what difference there is in the brands that I have stored for this winter.
This year I had 4 tons of pellets delivered and stored for my 2 Bosca Spirit 500 stoves. 1 ton is Atlas Ultra Premium Red Fir, 1 ton is North Idaho Energy Premium and the other 2 are Westwood Premium (which are re-branded Okanagan Pellets from B.C.). All of these brands are softwood pellets and are considered the best available in our area.
Using a thermometer (procedure similar to one I saw on this forum) I tested each pellet in a clean stove one bag at a time. I tested heat, ash and time it took to burn the entire bag. I used the 3rd highest of the 4 settings on my stove for the test. Here's what I got:
Westwood Premium: 265° and 12hr 18 min burn time (second lowest ash no clinkers)
North Idaho Pellets: 252° and 13hr 53 min burn time (lowest ash by far no clinkers)
Atlas Ultra Premium: 248° and 13hr 22 min burn time (highest ash no clinkers)
The burn time of the Westwoods jumped out at me and made me burn a second bag to make sure I didn't make a mistake. The time for the second bag was within a few minutes of the first bag (the time above is the average of the two).
After looking at the pellets themselves I found out why the Westwoods were both the hottest and had the shortest burn time. The pellet length is very short compared to the other two brands. Also they are very consistent in length. The short and uniform length allows more consolidation both in the hopper and in the auger allowing a higher volume of pellets to fall into the burn pot per revolution of the auger. I further confirmed this when measured the "high water mark" in the hopper when loading a single bag of each brand. The hopper was almost 2" "more full" with the North Idaho and Atlas pellets than with the Westwoods.
So while there is definitely a heat output difference that is dependent on quality of material used, there seems to be a direct correlation to size of pellet as well........at least in my less than scientific test.