Alternative Heating With Pellet Fuel Appliances

Green Architect

Coal, wood and gas have long been the standard fuel sources for heating our homes and powering our appliances. One alternative fuel source is gaining momentum and is super efficient — pellets. They're made from industry byproducts such as sawdust and wood chips, burn clean and can be used any a variety of heat sources such as fireplaces, furnaces and boilers. We recently attended a presentation on pellet appliances, find out what we learned about this super fuel source, after the jump.

During the 1970s energy crisis, Europe quickly latched on alternative heating options such as pellet stoves. It wasn't until the mid-2000s that pellet heating caught on in the US, but it is fast gaining momentum, and has nearly doubled in use since 2004. Pellet appliances have a high combustion, can burn up to +99% efficiency and can pack up to 113,00BTU.

Types of Pellets
The great thing about pellet fuel is it is typically derived from post-industrial recycled content such as sawdust or wood chips from the wood and furniture industry. Pretty much all pellets are bio-based and are from rapidly renewable sources, so in addition to wood-based pellets, there are also waste paper pellets, corn, sunflower seeds, nut shells and more.

Unlike wood burning fireplaces, which can sometimes burn dirty and ineffiecient, and have even been banned in some cities, pellet stoves are very efficient. Pellet heat provides a very convenient, economic and clean solid fuel source of heat. Compared to wood, pellets produce very little ash, and the ash it does leave behind is much cleaner and free of pollutants.

Appliance Options

  • Fireplace & Stoves: These appliances are the most common and least expensive option. When installed in a small and/or efficiently built home, fireplaces and stoves can be used as a primary or secondary heating source. Because of their construction and installation, they function much cleaner and efficiently than standard open front fireplaces. When more than one stove or fireplace is installed, they can be used as a primary heat source in a zoned system. A number of the appliances would be installed throughout the house in conjunction with thermostats to raise or lower the heat as needed.
  • Furnace & Boilers: Pellets can be used to fuel pellet furnaces and boilers much like their gas or electricity powered counterparts. Using ducts and heat exchangers heat can be transmitted through ducts or radiant heat, and can even power domestic hot water heaters.

Cost and Maintenance

According to the estimates we were given, bags can be bought for $4 per 40-pound bag, and depending on the grade of pellets used a single load will provide about 5 days worth of fuel. All pellets use hopers to store and feed pellets into the appliances — these hoppers can hold between 40-1400lbs of pellets. The frequency that pellets can be loaded depend on the type and size of appliance, but it could range from every couple of days to more than a week. The appliances typically come with an ash tray that might need to be emptied every few weeks, or about 4 times a year. The heat exchangers also need to be cleaned about as often.

The ease and cost of sourcing the pellets might depend on where you live and the season during which you buy. Pellet factories are very common in the midwest, whereas there is currently a shortage on the east coast. Additionally, pellets are typically on sale during the off-season, Spring.

Pellet stoves can cost between $1500-3000, and pellet boilers can cost around $6500. Additional accessories such as hoppers (bins to hold pellets) and battery backups can add an additional $600-1200.

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(Images: MCZ and Biomass System & Resources)