One component of having a green home is the energy type one uses. Generally speaking, if one is using a renewable energy source, the home becomes greener. It would seem to follow, then, that using wood, a renewable energy source, to provide heat or to supplemental heat to their homes is in the best interests of the environment. However, heating with wood tends to be both inefficient and is actually a cause of pollution.
Traditional fireplaces are generally straight up environmentally unfriendly. In a traditional fireplace, approximately 70 percent of the heat goes up the chimney, which translates to 15 percent efficiency at most (compared to near 100 percent for the most efficient gas furnace).
In fact, a fireplace sucks up to 9,000 cubic feet of a home’s previously heated air up and out of the chimney, which actually causes negative efficiency.
As bad or worse are the particulates and greenhouse gases which spew into the atmosphere. According to the Environmental Protection Agency (EPA), a fireplace ejects 28 pounds of particulates; an uncertified wood stove, 4.8; and a pellet stove, .49. This compares with only .013 for oil and .0083 for gas furnaces. Hydronic heaters, otherwise known as outdoor wood boilers, are not legal in Washington State, even if EPA qualified.
In fact, the air quality in the Tacoma-Pierce County Smoke Reduction area is so bad (and does not meet Clean Air Act standards), that the Puget Sound Clean Air Agency (PSCAA) has a program to buy back certain uncertified wood burning appliances because all must eliminated or replaced by Sept. 30, 2015.
Placing an insert into the firebox does provide marked energy efficiency. While a fireplace insert is good and a woodstove is better, a pellet stove insert is best. Nonetheless, efficiency and particulate emission are still never near that achieved with even an oil furnace.
Besides, an additional consideration is whether a burn ban is in effect. According to the PSCAA, when a Stage 2 burn ban is in effect in your area within Washington State, unless the wood burning appliance is one's only source of heat and one has applied for an exemption in advance, then one are not allowed to use your fireplace or wood stove.
All in all, however, using wood is still not as environmentally friendly as using natural gas, despite it being a fossil fuel.