If you weld together two rods of different metals, and start heating the junction, then a slight voltage will appear at their ends. At the beginning of the last century, according to this principle, heat generators were made to power walkie-talkies, which removed energy from the heat of the fire. You can repeat such a device at home, building it on the basis of Peltier elements.
- 4 Peltier elements – http://alii.pub/5p40l2
- 5V boost converter – http://alii.pub/5p40ra
- thermal paste – http://alii.pub/5p40vy
- aluminum profile pipe 20×20 mm;
- steel plate;
- steel scraper for washing dishes;
- candle pill;
- sheet aluminum or strip 40 mm.
Thermal power generator manufacturing process
To make a generator heat exchanger, you need to cut 4 blanks from a profile pipe 60 mm long.
They are drilled. 3 side walls made of an aluminum strip 40 mm wide are screwed to the obtained segments. At the bottom, they bend for the stability of the structure. The window formed by them under the heat exchanger is necessary to insert the candle.
For a Peltier element to produce electricity, one side must be cold and the other hot. Therefore, for each of them you need to assemble a radiator. It is made from the same aluminum strip or sheet as the side walls of the heat exchanger. The radiator consists of 3 blanks of different sizes, folded from two edges. Their fins must have such a bending angle so as not to interfere with neighboring radiators on the heat exchanger. It is convenient to bend by pressing the plates in the center, first with a 40 mm profile pipe, then 25 mm and 10 mm.
The parts of the radiator are drilled, in the places of contact they are lubricated with thermal grease. They must be tightened with countersunk screws. Next, you need to clamp the Peltier elements between the heat exchanger and radiators. With this configuration, this cannot be done with screws, so you can use clamps made of thin wire.
The thermoelectric generator is ready for use. A loose scraper for washing dishes is pressed into the tubes of its heat exchanger. It will allow you to more efficiently remove heat from the candle.
A candle is installed under the generator. In this form, it already gives out almost 1.5 V. This is not enough, so you need to connect a 5 V converter. For stability, it is better to screw the generator to the bottom of a metal bowl.
In order for the device to generate more electricity, additional wicks can be inserted into the candle 2.
After such a refinement, 4 Peltier elements give out almost 5 V. However, this is not enough for recharging a smartphone. The phone sees charging, but its current spending on screen backlighting is higher than the inflow, so it will be discharged. You can only charge an old push-button mobile phone when it is off. In reality, the charge is only enough to power a simple Arduino or LED lights.
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