What you are seeing in the picture is the start of a project that I’m currently working on. The purpose of the project is to make a miniature air conditioner, at least that’s what the final product is supposed to be. In the picture, you can see the main components of the project, a power source, a fan, a thermoelectric converter (TEC) and a light emitting diode (LED) for show. Most of the parts are pretty basic except for the TEC plate. The TEC plate is a ceramic plate that will generate the cold air needed to make this A/C. How is it going to produce coldness you ask? Well, I’m glad you asked. I’ll try to explain it as easy as I can so try and keep up.
The TEC plate works on the principle of the Peltier-Seebeck effect. This thermoelectric effect 1“is the direct conversion of heat differentials to electric voltage and vice versa.” What this means is that, as you apply power to the TEC plate, current, or the flow of electricy, is passing through two different semiconductors connected at two junctions and because these two semiconductors have different property, one side of the plate gets hot while the other side starts to get cold. The current takes the heat from one junction and disbursts it out the other junction. It does this because it is trying to return to the equillibrium that existed before power was applied by absorbing energy at one connector and releasing it at the other.
In order to make the cold side as cold as possible, I’ve attached a heat sink to the hot side. This will help draw the heat away from the hot side so that the cold side can get colder. Soemtimes the sides of this TEC has a temperature difference of 50 degrees Celsius. So if the hot side remains at 20 degrees Celsius, the cold side has the potential to be -30 degrees Celsius.
As you can see from the picture about, water droplets has formed on top of the TEC plate. The water droplets are made because of condenstation. I’m sure you remember that from middle school. Water vapour condenses onto another surface because the surface is cooler than the temperature of the water vopour in the air.
Now, if I pumped in enough power, eventually those water droplets would freeze into ice! If it does turn into ice, then I’ve got myself an A/C and all it costed me was 10 bucks.
Of course, using batteries won’t cut it. I have to build a transformer to regulate the power being used. This plate can handle 15V of electricy and all I’ve got to power it are a bunch of D size batteries. So it’s not going to freeze the water droplets that easily. I need better heatsinks, one to draw out the hot air and one to distribute the cold air.
If I make any progess I’ll let you know. Maybe I can sell the final product on eBay. Those people will buy anything!