You are here:
Black Carbon Emissions from Residential Wood Combustion Appliances Feb 2020
Citation:
Holder, A., T. Yelverton, A. Brashear, AND P. Kariher. Black Carbon Emissions from Residential Wood Combustion Appliances Feb 2020. U.S. Environmental Protection Agency, Washington, DC, EPA/600/R-20/039, 2020.
Impact/Purpose:
Particulate matter is one of the primary pollutants emitted from residential heating appliances, such as wood stoves. Black carbon, the light absorbing component of particulate matter, can darken light surfaces in snow covered areas and lead to increased heating of the Earth’s surface. Residential wood combustion in heating appliances used in these areas may be a major source of black carbon emissions. However, little is known about black carbon emissions from wood stoves in part due to a lack of appropriate measurement methods. The objective of this study was to measure black carbon emissions from residential heating appliances by several different measurement methods. Pollutant emissions were measured from three woodstoves spanning a range of manufacturing years and stove design. Black carbon emissions were assessed using a filter-based measurement method developed by the International Cryosphere Climate Initiative. Additionally, black carbon emissions were measured using continuous measuring instruments. The filter-based measurement method had increased uncertainty compared to the online measurements due to the high particulate matter concentrations emitted from these stoves. Accurate filter-based black carbon measurements from large stoves with high particulate matter emissions require more dilution to avoid overloading filters.
Description:
This report covers wood stove testing carried out by ORD during May 2018 to June 2018. Testing and analysis was completed as of October 2018. Three stoves of varying design and certification level were tested using the Black Carbon Protocol developed by the International Cryosphere Climate Initiative. Each stove was tested with spruce crib wood in a low and high burn rate conditions. Gas phase pollutants carbon dioxide, carbon monoxide, total hydrocarbons, and nitrogen oxides were measured continuously. Particle phase emissions were sampled on filters and analyzed for particulate matter (PM) mass, elemental and organic carbon. Continuous measurements of black carbon concentration were also made. Emission factors were quantified from each stove for each burn rate. Emissions of pollutants associated with incomplete combustion (carbon monoxide, total hydrocarbons, and PM) were generally highest from the low fire condition. The overall efficiency of each stove varied by stove type/vintage, with the newest stove showing the highest efficiency and the oldest stove showing the lowest. Filter -based black carbon emission factors calculated following the protocol were generally higher than those calculated using a carbon balance emission factor calculation method. The differences in emission factors are likely due to the adjustment to account for particle losses in the duct and sampling systems, inaccuracies in the duct flow measurement or inaccuracies in the fuel moisture.