Stoves, fireplaces, and furnaces in American homes burned 42 million cords of wood in 1981, according to a Forest Service survey. If stacked 8 feet wide, all that wood would produce a wall 44 feet high stretching from Washington, D.C., to San Francisco's Golden Gate.
The heat potential in that cordwood amounted to 9 percent of the heat available in all the other heating fuels used in the United States that same year.
Unfortunately, only about one-third of that energy ended up as useful heat in American homes. That's because most of the wood was burned in inefficient open fireplaces and poorly constructed stoves, as well as in a partially green state.