# Vapor to Drinking Water

How a humidifier's mist turns into invisible vapor, and how a cooled fin and filter system can gather that moisture from room air into a glass of drinking water\.

By quiet\-moon\-fa93a64e

Topic: Engineering

[Open the interactive Jig](https://ask.jig.com/j/6ETdPKHAFxCa)

## Transcript

### 1. From mist to a glass

A humidifier puffs cool mist into a room\. Beside it, a compact water maker pulls that moisture back out of the air\. Follow the water from mist to a glass you could drink\.

### 2. Shaking water into mist

Under the water sits a small ceramic disc that vibrates one to two million times a second\. It shakes the surface so hard that tiny droplets fly off\. Nothing boils: this cool mist is not steam\.

Each droplet is about one micron across, a thousandth of a millimetre\.

### 3. Mist becomes invisible vapor

The droplets soon evaporate into water vapor: single water molecules mixed into the air\. Vapor is invisible, so the mist seems to vanish\. Minerals from tap water stay behind as fine white dust\.

### 4. Pulling in the damp air

In the water maker, a fan draws humid room air in through the grille\. The air carries its invisible vapor toward a block of thin metal fins\.

### 5. Cold fins turn vapor into drops

A Peltier tile is a thin ceramic square that moves heat when electricity flows through it\. One side gets cold, close to freezing, while the other side gets hot\. On the cold fins, vapor condenses into beads, like dew on a cold can\.

A small Peltier unit collects only a few hundred millilitres a day\.

### 6. Catching every drip

Gravity pulls the beads down into a tray and on into a collection tank\. This water came from vapor, but it is not clean yet\. Dust, germs and traces of metal from the fins can ride along\.

### 7. Two filters

A pump pushes the water through a carbon filter, which traps dust and odd tastes\. Next comes a very fine filter with holes about 0\.3 microns wide, small enough to stop bacteria\.

Viruses are smaller still, so the next step matters\.

### 8. Germs switched off, then a glass

Last, the water passes a germ\-killing ultraviolet lamp before it reaches the tap\. At home, a rolling boil for one minute also kills germs\. Press the tap paddle to pour a glass\.

### 9. Why a humidifier is not enough

A humidifier only spreads tap water into the air; it never cleans it\. Drinking water from air needs a machine with food\-safe parts, filters and a germ\-killing step\. Boiling kills germs, but it cannot remove metals or chemicals\.