Treehugger.com has been publishing articles on Ethanol Fireplaces and indoor air quality since 2007. And to be fair they have done a good job of presenting a well rounded presentation of the facts. But when they chose to present a study by the Fraunhofer Institute for Wood Reasearch, they may have crossed the line on objectivity. While they did note that it was not surprising the Fraunhofer Institute found burning wood to be a cleaner and safer interior solution:
It should be noted that the study was done by the Fraunhofer Institute for Wood Research, which not surprisingly found that properly sealed and vented wood burning stoves resulted in significantly cleaner interior air.
They did appear to present this research as definitive:
On the basis of this study it appears that these pretty ethanol fireplaces that are popping up everywhere are not so innocuous after all.
There are always two sides to any story, and then there are facts:
During ethanol fermentation, glucose and other sugars in the corn (or sugarcane or other crops) are converted into ethanol and carbon dioxide.
C6H12O6 → 2 C2H5OH+ 2 CO2 + heat
During combustion ethanol reacts with oxygen to produce carbon dioxide, water, and heat:
C2H5OH + 3 O2 → 2 CO2 + 3 H2O + heat
- excerpt from Wikipedia
Lumina Products, Inc. is the producer of SMARTFUEL™ Ethanol Fireplace Fuel. Aside from denaturants required by the TBA (our proprietary formulation), a small amount of a bitterant and water is all that’s added – its as pure as ethanol gets. We have had our fuel tested in several 3rd party independent laboratories, and when burned they have confirmed the only detectable exhaust was CO2 and Water Vapor.
Now that fact alone might make you think that the subject is closed. But in fact it is still not the complete story. When ethanol is burned and a complete combustion occurs – that is the case – only byproduct is CO2 and Water Vapor. However, if the combustion is incomplete we can expect to see CO (carbon monoxide) produced at low levels. So it is important that the fireplace or burner being used ensures that complete combustion is taking place.
The most common problem is a poorly executed damper added to the design of an open tank burner in an attempt to control the burn rate of the ethanol. When the damper is closed down, it starves the fire of oxygen required for complete combustion and can result in production of CO, possibly generating soot as well.
Another cause of incomplete combustion could be attributed to poor design of the firebox and fuel reservoir of an open tank burner. With open tank burners you are basically burning ethanol fumes being emitted from the top layer of ethanol inside the reservoir. As the ethanol is consumed and the fuel level drops, the flame actually is burning down inside the fuel reservoir. If the burner is not designed to accommodate this, as the flame recedes further down in the reservoir adequate oxygen may no longer be present to ensure complete combustion. Not all burners exhibit this problem, so this is not ‘de facto’ across the board. But it is a possibility that should be considered.
There is newer technology emerging in the realm of ethanol fireplaces and burners that address this specific issue. These are electronically controlled and monitored fireplaces such as those produced by aFire (distributed in North America by Lumina Products, Inc.). These burners have a sealed fuel reservoir. The fuel is pumped by a medical grade mechanical pump into a shallow combustion tray at the top of the burner. The fuel is regulated to ensure complete and clean combustion. At the same time the onboard electronics monitor several safety factors including CO2 production, Temperature, Seismic motion and Tilt. Should any abnormality be detected, the unit will automatically shut down at once. These are premium units and carry a higher price tag. But they are much more sophisticated, allow for more flexibility in installation, and in the case of aFire the fireplaces and burners can be controlled via a remote, your smartphone, or can be integrated into your home automation system.
We maintain that many of the open tank fireplaces on the market operate in a manner that ensures complete combustion and therefore burn clean. And certainly these newer electronic units raise the standard and provide greater piece of mind.
Results suggested by studies like the one presented by Fraunhofer, need to be taken with a ‘grain of salt’ understanding their particular bias. Tree Hugger should have made this even more clear in their summation. And both Tree Hugger and Fraunhofer failed to mention that in a large part of California it is now illegal to operate a wood burning fireplace due to air quality issues.