Here's how to burn your fire cleaner and more economically
Follow these five simple and practical steps to improve your woodstove’s fuel efficiency and reduce hazardous air pollution emissions.
Step 1. Burn the right fuel
Use fuel that burns efficiently and cleanly. Pellets burn far more cleanly than wood logs. If using firewood however, use properly seasoned wood that is harvested in the spring and allowed to dry over the summer for at least six months. Store wood outdoors, off the ground (to stay dry), and with the top covered but the sides left open (to allow air to circulate). Use logs that are evenly colored, and have a moisture content of 15-20% at most (firewood moisture meters are available for under $20 and can be a great “burn right” investment). Many materials release noxious emissions when burned, are highly inefficient and can coat your chimney quickly, leading to smoking and more frequent cleaning (and in the worst case, chimney fires). To avoid this, don’t burn paper and paperboard, paint, glue, waste, rubber, diapers, magazines, leather, garden waste, or other materials not recommended by the stove manufacturer.
Step 2. Flip your fire upside down
Yes, you read right – upside down! The conventional method of lighting kindling below a pile of big logs releases excessive smoke. While pervasive, this approach is neither necessary, nor efficient. Lighting the fire from the top and letting it slowly catch on to larger logs on the bottom is more efficient and releases less pollution.
Start by spreading dry logs throughout the combustion chamber. Use larger logs on the bottom, layer on thinner logs, and finally add sticks, bark or wood chips to the top. Make sure not to over-pack the logs or stack them higher than the manufacturer’s instructions recommend (usually filling about half the combustion chamber with logs is a good rule of thumb). Then light the top of the pile, using commercially purchased fire starters if you lack good dry chips or sticks for kindling.
Voila! An upside down fire, and a sure-fire way to impress your friends! Read more about Top-Down fires.
Click here for the latest research on why lighting from the top cuts emissions even for new, modern stoves.
Step 3. Keep the fire burning hot
Keep the fire burning hot to ensure that the combustion chamber never cools down. A hot fire is a clean fire; most harmful emissions come from the start-up and cool-down phases of the burning cycle. So when the fire really gets going, you can start adding bigger logs and packing them closely together. Keep adding more logs periodically to make sure your fire is continuously burning and hot. One of the most common mistakes is to simply load the firebox and let it burn down before adding more fuel — this both decreases heating efficiency, and increases the amount of wood you use as well as dramatically increasing harmful pollution.
Step 4. Check out the color of the smoke
If everything is in order, you should not see any smoke in the firebox or from your chimney. Black and yellow smoke means that the fire is releasing a lot of emissions.
Step 5. Use a clean and efficient stove or boiler (or replace your old one)
Low-emission stoves are designed to promote efficient burning and reduce air pollution emissions, including climate-damaging black carbon. If you have an older stove, consider upgrading to a newer model certified as low emitting by the U.S. Environmental Protection Agency or the Nordic Eco-Label. See list of EPA-certified stoves.
Of all solid fuel burning appliances used for residential heating, those that burn pellets are the cleanest. Pellets are usually made of wood but can be made from other organic materials too. If you’re committed to burning wood logs, use a fan to boost combustion efficiency or a catalytic converter to reduce harmful emissions.
Getting a modern, clean stove means you will spend less on fuel for the lifetime of the appliance.
That’s it! These five simple steps will burn less fuel, reduce your wood stove or wood furnace emissions, improve air quality, slow climate change, AND save you money.