The pellets or wood pellets
Called Pellets or pellets depending on the region, they are made of "granulators" from sawdust (sawmill waste generally), it is the most "fashionable" mode of wood heating currently.
For the anecdote, their origin is (despite what we think) already "old" because their birth goes back to the end of the Second World War in America. Indeed; Millions of tons of sawdust and millions of pallets made or accumulated during the US war effort had to be disposed of.
Their height is 6 or 8 mm in diameter and their length to 1 3 times their diameter (see standards Pellets).
Contrary to what one might think their cohesion is achieved only by sintering (mechanical compression): no glue type binder or other additives!
Their humidity is less than 10%, manufacture therefore requires a rigorous drying but this is not the only step obviously. To learn more about the production of pellets, this is the diagram of a pellet manufacturing plant or wood pellets.
Pellets are usually sold "standardized" but remember to ask your supplier because it is not systematic. Indeed; in 2009, there was no mandatory standardization in France or Belgium to manufacture and sell pellets, but this will evolve with Europe in the coming years to ensure consistent quality for consumers. The pellets are delivered either in bulk for pellet boilers via a blower truck (requires a specific storage silo with pellets) Or bag (usually of 15 kg) more convenient for pellet stoves.
There are (at least) 2 big advantages over wood logs: the ash production is very low and their use is "automatable", so we find the comfort of using oil! The interested reader will read this very complete file on the Heating with pellets by realization and presentation of the pellet boiler or visit our forum on wood heating.
The main disadvantage of pellets is that you need to equip a special device Pellets can generally burn THAT pellets. The pellets can still burn in a log burning stove provided to burn logs or sticks together.
Price and energy equivalent wafers
One tonne of pellets equivalent to about 500 liters of fuel oil and the storage volume is of the order of 3 4 times to the oil volume.
Here also the prices are very variable, they can be equivalent to the oil as being 50% cheaper, it depends on the time! The attentive reader will look carefully theComparative price developments Pellets in "real time" from 2006.
Learn more about wood pellets
- Read a complete dossier on the Heating with pellets by realization and presentation of the pellet boiler
- the properties and standards for wood pellets.
- Evolution of the price of pellets and comparison relative to oil, gas and electricity