A little bit of theory.
Single element thermoelectric module (TEM) is a thermocouple consisting of two dissimilar elements with p- and n-type conductivity. The elements are connected to each other using a copper connection plate. Semiconductors based on bismuth, tellurium, antimony and selenium are traditionally used as element materials.
Thermoelectric module (Peltier element) is a set of thermocouples electrically connected, usually in series. In a standard thermoelectric module, thermocouples are placed between two flat aluminum oxide or nitride ceramic plates. The number of thermocouples can vary widely - from a few to hundreds of pairs, which makes it possible to create TEMs of almost any refrigeration power - from tenths to hundreds of watts.
When a direct electric current passes through a thermoelectric module, a temperature difference is formed between its sides - one side (cold) is cooled, and the other (hot) is heated.If effective heat removal is provided on the hot side of the TEM, for example, using a radiator, then on the cold side you can obtain a temperature that will be tens of degrees lower than the ambient temperature. The degree of cooling will be proportional to the current. When the polarity of the current changes, the hot and cold sides change places.
Practice.
Pelte elements are widely used in cooling systems. But not many people know about their other property - generating energy. This laboratory work is devoted to the study of these capabilities.
50*50 mm element, installed between two aluminum bars. Their surfaces are previously ground in and lubricated with KPT paste. One of the bars has through holes drilled through which a copper tube is passed for water cooling. Here's what happened:
Connect the water to the cooler to one side Peltier element, and put the other one on the burner. We connect a 10W 6 volt light bulb to the output of the element. The result is that our generator is working!
Experience proves that the Peltier element produces electricity well. The light burns quite brightly, the voltage is about 4.5 volts.
Heating up to 160 degrees was not optimal; at 120 degrees the result was only 10% worse.
The coolant temperature at the outlet is ten degrees, at the inlet it is one degree less. Judging by these results, water is not so necessary for cooling...
With help Peltier elements You can generate electricity on an expedition, on a camping trip, at a hunting winter hut, in a word, in any place where it may be needed. Naturally, if you have firewood or bright sunshine, and definitely some ingenuity.
Using a thermoelectric module.
Such a thermoelectric generator is well remembered by those who remember Soviet state and collective farms. They say that during the war the Germans could not understand how the partisans could conduct radio broadcasts for a long time from a besieged forest.
Yes, as they say - if our scientists were paid money, they would have invented the iPhone back in `85! :-)
Thermoelectric refrigerator
Thermoelectric refrigerator (option 2)
Thermoelectric refrigerator (option 3)
Car cooler for canned drinks
Drinking water cooler
Thermoelectric air conditioner for KAMAZ cab
Water is poured into such a “ladle”, placed on fire and, please, recharge your mobile phone. The whole secret is in the bottom, Peltier is “buried” there
Let's take a closer look at this design.
Currently, there is growing interest in the use of thermoelectric generator modules in household devices. First of all, this concerns the possibility of powering low-power consumers of electricity - radios, cell and satellite phones, laptop computers, automation devices, etc. from existing heat sources. A thermoelectric generator, which has no rotating, rubbing or any other wearing parts, allows you to directly obtain electricity from any heat source: exhaust gases of internal combustion engines, hot water from geothermal sources, “waste” heat from thermal power plants, etc. Guided by the experience gained in the creation of industrial thermoelectric generators (TEGs) of various powers - from several Watts to several kiloWatts, IPF CRYOTHERM began mass production of household TEGs with a nominal power of 8 W.Structurally, the generator is made in the form of an aluminum bucket with an internal volume of about 1 liter, in the bottom of which generator modules produced by IPF Kryotherm are installed.
The temperature difference necessary for the generator to operate is achieved when the ladle is heated, for example, by the flame of a fire. The water heated inside the ladle can be used for cooking or other purposes. This generator is primarily intended for use in remote, hard-to-reach places to recharge batteries for individual communications and navigation equipment, lighting, etc. It is indispensable for hunters, tourists, sailors, rescue and special services employees who are forced to stay away from central power supplies for a long time.
The advantage of the generator is its low weight and volume, high specific generated power, functionality and high reliability. The design of the generator eliminates the possibility of overheating when used correctly. As an additional option for the generator, a step voltage stabilizer with ranges of 3 V - 6 V - 9 V - 12 V and adapters for chargers are offered.
HOUSEHOLD THERMOELECTRIC GENERATOR 1TG-8
Data sheet
Weight without liquid, kg, no more than 0.55
Overall dimensions, mm
with a handle
without handle250x130x110? 123, h=100
Internal volume, dm31.0
Rated generated power, W, not less than 8.0
Output voltage, V3.0? 12.0
Current, mA660 ? 2660
And here is another example of use.
The generator consists of such small thermoelectric capacitors.
Thanks to the use of the latest materials, thermoelectric generators (TEGs) are already capable of generating electricity with a power of up to 1000 W.
The thermal generator will especially please fans of dynamic driving: after all, the higher the engine speed, the more electricity is generated, which in the future can be used in hybrid power plants, for example, for even better acceleration dynamics.
Almost two-thirds of the fuel energy in modern internal combustion engines “flies” into the atmosphere along with heat. Therefore, BMW engineers, together with specialists from the American aerospace agency NASA, are actively working on technologies for converting the thermal energy of exhaust gases into electrical energy. Such installations have another positive effect: additional heating of a cold engine. For now, TEG “envelops” a section of the exhaust pipe, but in the future it is planned to integrate this system into the catalyst, thereby using its thermal regime. For a larger scale implementation of this technology in the car, the underbody will have to be modernized, expanding the central tunnel in some places. It is expected that such a system will very soon be able to provide 5 percent fuel savings, increasing the efficiency of the internal combustion engine.
This is what a Peltier element or thermoelectric module is!
