Over the years I’ve been asked on several occasions about homemade pellet mills. As you may know from reading my post on how to make wood pellets, the process is not as straightforward as many people make out. Those people include resellers of cheap Chinese pellet mills. The quality of many small pellet mills is not very good in most cases. Therefore it appears some people are interested in trying to make their own pellet mill from home. There are various videos on YouTube of such projects, and I’ve included an example of a homemade pellet mill below.
Example of a Homemade Pellet Mill
The video above is of a small homemade pellet mill made in the EU. They have based the design on a small flat die machine and they appear to be producing wood pellets to a reasonable quality. The design is very simple, the material is fed from the top and they have a fixed die and a rotating roller carriage which is forcing the material through the die. They have a fairly low gearing which will provide them with good torque to produce better quality pellets. However, the productivity of this small homemade pellet mill is going to be very low, probably about 10kg/h.
Homemade Pellet Mill Rollers and Dies
Something to note about most homemade pellet mills you will see on YouTube is that they are not totally ‘homemade’. Often as the case appears with the video above the rollers and die are actually sourced from China. I recognise the rollers and die from a range of flat die Chinese pellet mills I’ve seen in the past.
Therefore, the homemade element of these builds is actually to do with the pellet mill housing, gearbox, motor and electronics. Realistically, this is the most practical means to produce a homemade pellet mill. As pellet mill dies and rollers are made from a specific grade of carbon steel which is then hardened to ensure a reasonable operating life. No one has the ability to hardened steel rollers and dies at home. Therefore sourcing these parts from existing pellet mill manufacturers is really the only viable option.
You could make the die and rollers from machined steel and skip the hardening process. However, the rollers and die of your homemade pellet mill would probably last under a hundred hours of operation before they were worn out. Also, a die is drilled to a specific compression ratio with an inlet taper to suit the material being processed. Trying to make your own dies would take a lot of trial and error to produce a suitable grade of wood pellets for stoves and boilers.
Does it make sense to produce a Homemade Pellet Mill?
While you may be able to produce a homemade pellet mill such as that in the video above, is it really worth the effort? A homemade pellet mill as seen in the video requires constant supervision. Also, you have first have to source and prepare a suitable raw material to the right particle size and moisture content before you can even think about using it in a homemade pellet mill.
Homemade Pellet Mill Economics
So let’s say for instance you are producing between 10-20kg/h an hour of wood pellets with a homemade pellet mill. It will take you around 66 hours to produce 1,000 kg/h which has say a value of £230/$290. You are effectively paying your self under £3.50/$4.40 an hour to operate the homemade pellet mill. Within that time you also have to cover raw material costs/preparation and the payback on the equipment you purchased.
When you add up the cost of equipment and time to produce wood pellets for fuel at home it’s not really viable. To be honest, a much better idea would be to invest the money into a larger wood pellet storage silo so you could get a lower price per tonne. With a wood pellet silo, you could have loose bulk deliveries of wood pellets via tanker instead of bags.
When might a Homemade Pellet Mill project work?
Small flat die pellet mills from China are often not made to the best quality. Therefore by building a homemade pellet mill you would probably be using better quality parts. As stated above, the economics of a homemade pellet mill means you will not be doing it for cheaper fuel for your pellet stove or boiler. Really, it would only be a hobby project with one exception, BBQ wood pellets.
If you’re not sure what BBQ wood pellets are, I’ve got a post about Traeger and their BBQ wood pellet plant. Basically, BBQ wood pellets are easier to use than charcoal and produce a better flavour than cooking on gas.
BBQ wood pellets are the most profitable wood pellet fuel you could produce. To the point where even on a small scale with a homemade pellet mill producing 10-20kg/h, you could actually make a profit. The thing with BBQ wood pellets is there are so many different blends and flavours. If you could produce your own unique flavour and establish a brand you could make a profit producing BBQ wood pellet from home. So that’s something to think about, first though you really need to learn as much as you can about how to make wood pellets before even consider making a homemade pellet mill.