As Summer ends it is time to think about what you are going to do to keep warm this Winter. Our neighbour who is renovating, gave us a pile of waste hardwood, to burn in our slow combustion wood fire. This would otherwise have been destined for landfill. Fuel pellets take this concept a step further. Fuel pellets created from waste sawdust and other organic materials, burn with greater efficiency and lower emissions than wood, so we were keen to find out more.
The fuel pellets can be created from various biomass sources, including compacted sawdust, agricultural waste, in particular sugar cane, but also wood chips, waste paper and other organic materials. The pelletising process involves breaking up the source material, drying it so the final product has a moisture content below 10%, then applying pressure to force it through a screen. This produces uniform pellets with a much higher density than the original materials. The final pellets have a density four times greater than traditional wood products and due to their small uniform size, can be more efficiently transported in bulk.
According to the Water, Materials, Energy, Strategy magazine (February 2010) there is a rapidly growing customer base. The president of Global NRG, a private company specialising in waste to energy projects, has even considered the use of the Northern Territory’s woody weeds as a fuel source. The government spends millions trying to eradicate and control these, and harvesting them for commercial purposes would reduce the environmental damage and fire risks they pose, and the pellets could be exported or used to fire power plants for remote mine sites.
You can buy pellet heaters for the home. Although these look the same as wood stoves, pellet stoves have a hopper full of extra fuel that sits above the flames. The pellets are gravity fed into the stove at a constant rate. Most have a feeding mechanism that ensures the right amount of fuels is added to the fire. Pellets burn more efficiently than wood and pellet stoves are credited with providing even heat that spreads from the stove. You can apparently burn pellets in a traditional wood stove by getting a wood stove insert.
So this is another thing to think about when planning the eco renovation.