Does focusing on getting people to switch to newer stoves work? Did it work after one town spent $2.5 million on a massive changeout program?
A large wood stove changeout took place in Libby, Montana from 2005 – 2008. Over $2.5 million was spent to replace most of the wood stoves in the Libby area with EPA-certified ones. They also invested in education programs and proper installation. Most participants in the changeout received a new wood stove, but a small number switched to a cleaner method of heating such as electric or propane.
In the immediate years after the exchange, wood smoke-related particulate matter mass was reduced by just 28%.
In the immediate years after the exchange, wood smoke-related particulate matter mass was reduced by just 28%. If the subsidies had instead gone to install propane or electric heat for everyone, particulate pollution levels would have dropped almost 80 percent, while also reducing toxins and carcinogens.
However, levels of toxic, carcinogenic Polycyclic Aromatic Hydrocarbons (PAHs) stayed the same. And potentially harmful resin acids increased significantly.
There were “highly variable” levels of emissions across homes that had received new certified wood stoves. Some houses did not ultimately experience any reduction in PM2.5 at all.
And four years after the end of the exchange, there were “highly variable” levels of emissions across homes that had received new certified wood stoves. Some houses did not ultimately experience any reduction in PM2.5 at all. So some neighbours of the replaced wood stoves suffered more than others.
Australia town sees a 40% reduction in fine particulates
Meanwhile, Launceston, Australia had a program that resulted in the number of households heating with wood dropping from 60% to 33%. PM10 (includes PM2.5 and particles up to 10 microns) levels dropped by about 40% and wintertime respiratory deaths were reduced by 28% for men and women combined.
Read more on the website much of the above information comes from: https://woodsmokepollution.org/wood-stove-changeouts.html
100% switch to clean heat would make a huge difference
This table from an Environment Canada report “Impact of Residential Wood Stove Replacement on Air Emissions in Canada” shows the amount of PM2.5 and other toxins from all non-wood residential heat sources in Canada. These non-wood energy sources represented 88% of all energy used for residential heat across the country at that time; yet they represented only 3.8% of all PM2.5 emissions.
Wood heat (which represented only 12% of all heat for homes) put out 96.2% of PM2.5 emissions in the home heating sector.
Click to enlarge
The table shows how the numbers might change if those stoves and fireplaces were all upgraded to new certified stoves.
Even when 100% of the stoves are replaced (first highlighted line), the numbers still are HUGE when compared to all of those other heat sources that represent 88% of all heat. We would still have annual PM2.5 emissions in this sector of 50 kt. And these numbers are based on the assumption that everyone used their stoves really well, burning hot and burning only dry wood…. The proven reality (such as in Libby, Montana) is that real world emissions would likely be much higher.
However, if all stoves were replaced with cleaner sources of heat the numbers drop by leaps and bounds. In other words, things would be far cleaner and healthier!
Total PM2.5 emissions for all home heating would drop to 7.7 kt!
How to guarantee success?
The best way to guarantee a home (and therefore a town) does not have a wood smoke problem? Move it to a cleaner heat source!
This would also save public dollars as there would be no need to invest public funds in ongoing education about burning, or in enforcement if the education fails.