OUT OF THIN AIR

PULLING MOISTURE FROM THE AIR MIGHT HELP YOU FIGHT A DROUGHT.

Dana Benner

As I write this piece, the western part of the United States faces record-breaking heat and massive drought. Here, in the Northeast, we're also dealing with high temperatures, a three-year drought and no Train insight. In some areas, water restrictions have gone into effect.

The lack of normal winter snows has left wells and reservoirs extremely low... or, in some cases, dry. My cistern, which allows me to capture rainwater I use to irrigate my garden, is bone dry.

So, as I sat and watched my garden struggle, I knew I needed to come up with a plan. That's when it dawned on me to get water from ... the air.

OLD CONCEPT

The idea of getting water from the atmosphere is nothing new. The very rain we're all praying for uses this process. Just watch the weather, and you'll often see rainstorms occurring when a warm front merges with a cold front. When moisture-rich, warm air clashes with dry, cold air, the moisture turns to either a liquid (rain) or a solid (snow and ice).

Because both are heavier than air, they fall to the ground. This process can also be seen when you put a cold bottle of water into the hot, humid air. Water droplets form through condensation on the outside of the bottle.

The water is in the air, so the question is, “How can we harness that water?"

AIR CONDITIONERS AND DEHUMIDIFIERS

We've already developed a way to harness this natural process-at least on a small scale.

It comes in the form of air conditioners and dehumidifiers. Both inventions take warm air and pass it over coils of cold air.

In the case of air conditioners, warm air is pulled from the outside and is run over coils of cold gases. The cooled air is blown back into the room, office or vehicle, and warm air is exhausted to the outside. The resulting water droplets formed when the warm air meets the cooling coil are expelled to the outside or into a receptacle, to be emptied later.

With dehumidifiers, the process is exactly the same, except the warm, humid air comes from inside the building, and the water droplets are dropped into a container, which needs to be emptied when full. Why can't this collected water be used to water my garden; and, if it can be used for this purpose, why not for drinking water? To test my theory, I started to bottle the water collected in recycled, 1-gallon, food-grade plastic jugs. In a single 24-hour period, my dehumidifier produced 3 gallons of water. This isn't even counting the water produced by my air conditioners. Three gallons don't seem like much, but we're only talking about one home dehumidifier-and a small one, at that.

COLLECTING THE WATER

Generating the water is one thing, but collecting it is another. Dehumidifiers usually have a collection container that holds the water until you empty it. Some even have hose adapters that'll drain the water as it's generated.

When it comes to air conditioners, water collection can be a little more difficult. The new, stand-alone style of air conditioners, for which the unit sits in a room with only a hose going out the window to exhaust the hot air, is constructed quite similarly to dehumidifiers. These air conditioners have a water-holding system, and the water is discharged from a port (or, in some cases, two) that's located on the back of the unit.