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Modern Wood Pellet Combustion Systems are Clean

Burning wood generates smoke and particulate emissions, doesn’t it?

A common misconception is that all wood burning is bad, and for clarity, WoodPellets.com, the Alliance for Green Heat, the Biomass Thermal Energy Council and the Pellet Fuels Institute all support stringent controls on emissions from biomass heating systems.

Uncontrolled burning of wood in non-EPA certified wood stoves and fireplaces creates smoke, creosote and significant emissions issues. However, wood is an uncontrolled fuel source, with anywhere from 20-40% moisture present when burned for heat in homes. Flakes of wood break off in combustion and can float up a chimney, never completing combustion, resulting in smoke and issues with particulates.

However, wood pellets are a highly refined heating fuel, which are dried to a uniform 4-6% moisture content. They are burned in well controlled systems that run extremely hot and with sufficient airflow to ensure complete combustion. As a result, with roughly 2 million tons of pellets being burned annually in the United States, particulate emissions from wood pellets only amount to <1% of the particulate emissions from forest fires and <2% of the emissions from less well controlled wood combustion.

Wow, it looks like our biggest PM emissions problem is forest fires!

Actually it is. Many years of aggressive fire suppression in some areas of the country, coupled to a lack of active logging have led to dangerously high fuel loads in forests. Then, when lightning strikes, dangerous fires can start rapidly and be difficult and dangerous to extinguish, as has often been the case in the West in recent years. Because these uncontrolled fires result in much, much higher emissions of particulate matter and other pollutants than modern pellet stoves, sustainable harvesting of forests can actually reduce emissions and is supported by the US Department of Agriculture and the Fire Service.