 gets distilled right along with the water because there are some, for instance, alcohol and other things that come along. Now, the reason they leave a gap is a lot of those vapors will flash off at that point, and only the water will drop into your reservoir. But it's really an effective, and it only costs about, even at 13.5 cents is what I pay for electricity, it only costs about 10 to 15 cents to distill a gallon of water.