Heating with wood pellets


 
Ever thought about heating systems that use wood pellets?  This fuel type is known as solid fuel / biomass, a renewable fuel source that is currently manufactured in most regions of North America, making wood pellets a locally supplied product.  Wood pellets are typically made from the waste byproducts of wood product manufacturing, including compacted sawdust and sawmill wastes, as well as from leftover material of the logging industry.   Although wood pellets resemble a recycled wood pet litter available in American supermarkets and pet stores, the type used for wood fuel in the US market is manufactured to achieve less than 10% moisture content.  The criteria of this standard was originally developed by the Pellet Fuels Institute, which has now engaged the American Lumber Standard Committee to serve as the accreditation body for the PFI Standards Program.


Commonly available products that convert wood pellets into heat are fireplace inserts and wood pellet stoves, both of which are classified in the CSI system under Division 10 Specialties.   Modern designs of pellet burning stoves are available from Wittus, Enviro and Rika (which was previously marketed in the US as Austroflamm).  A design from Breckwell that saves space is a window-mounted pellet heater.   While pellet stoves require electricity to function, some models use battery packs for backup in an electrical outage.  See the US EPA's Burn Wise section for  provides a list of certified wood

Another product that uses this solid fuel is the wood pellet boiler, which can replace fossil fuel boilers for hydronic heating (hot water) and forced-air systems (by incorporating a hydronic coil).  Vermont-based Pellergy manufactures and distributes a retrofit system for standard fossil-fuel boilers that converts them into a wood pellet central heating system.  On new construction, Pellergy offers a boiler unit with wood pellet supply system.

How efficient is wood pellet fuel?  Of course, efficiency will also depend on household habits, heating appliance, building envelope design and regional cost differences.  According to Connecticut-based Preferred Pellet Services, a 40-lb bag can provide up to 24 hours of heat and a typical winter's supply is roughly 100-150 bags of wood pellets.  So, let's say 110 bags at 40-lbs a bag (about 2 tons) will cost about $540 (based on pricing found at Primo Pellets which delivers to CT, RI and MA).

Do you currently use wood pellets or would you ever consider using them?


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