Ah, the cool, crisp days of fall! It conjures up images of brisk nights spent curled in front of a blazing fire. But that cheery fire is not so cheery for the environment. It may look pretty, but if you’re burning plain old wood in that fireplace, you’re belching lots of smoke, soot and other unpleasant stuff into the air. Add in the fact that the typical fireplace isn’t even really efficient at heating the house and suddenly a crackling fire starts to lose its appeal.