We Are Developing Local Ventilation Units with Peltier Modules
Experts from the University Centre for Energy-Efficient Buildings of the CTU are working on the development of a local ventilation unit allowing for regulation of the temperature of supply air. Its use is one of the ways to satisfying the demands on the quality of indoor environment, healthy building and satisfaction of inhabitants that have been getting more attention recently.
The device has the form of a larger radiator and it is designated for air flows of the volume of 50 to 150 m3/h. On one hand, it does not achieve such high efficiency as compressor-cooling units; on the other hand, it is much simpler from the construction point of view and there is an assumption of longer lifespan and lower investment costs.
It allows for post-heating of the supply air in the winter season and for its post-cooling in the summer season. It uses the so-called Peltier effect which helps pass the heat from the waste air going out of the room to fresh supply air (heating mode). In the opposite mode, it allows for post-cooling of the supply fresh air.
Just as with other similar devices, it contains a counterflow plate heat exchanger, fans, filters, regulation system and power supply. Compared to ordinary ventilation units, it also contains the so-called active exchanger with Peltier modules which allows for regulating the temperature of the supply air. It is capable of heating the exterior air by as much as 30 °C or of cooling it by about 12 °C in real operation.
Peltier module is a semi-conductor component, usually shaped as a small plate (edges 20 to 80 mm long, thickness of about 4 mm). It consists of a matrix of inter-connected semi-conductors of the P and N type, covered with a non-conductive ceramic plate on both sides. After connecting to the direct-current (DC) circuit, one side of the module warms up and the other cools down. As a result, the module works as a small heat pump, i.e. it takes heat in on the cool side and emits it back on the warm side.