Vacuum Tube Solar Energy Working Principle: How is Heat Produced?

Vacuum tube solar energy systems efficiently convert solar radiation into heat using the principles of physics. As Wholesale Solar Energy, we explain the science behind the systems we offer at wholesale prices from the manufacturer.

Solar Radiation and Energy Conversion

The sun emits 3.8 x 10²⁶ Joules of energy per second. A small part of this energy reaches the Earth, and solar energy systems capture this energy. The selective absorber coating on the surface of the vacuum tubes absorbs visible light and infrared radiation in the 0.3-2.5 micron wavelength range.

Physical Basis of Vacuum Insulation

Heat transfer occurs in three ways: conduction, convection and radiation. The vacuum environment almost completely eliminates conduction and convection. The 10⁻³ Pa pressure between the inner and outer glass prevents air molecules from carrying heat.

Heat Pipe Technology

The copper heat pipe inside the vacuum tubes contains a special fluid with a low boiling point. This fluid starts to evaporate at about 25-30°C. The vapor rises to the top of the tube, condenses in the manifold and transfers its heat to the water. The condensed fluid flows down again and the cycle continues.

Thermosiphon Principle

Hot water is lighter than cold water. This density difference provides natural water circulation without the need for a pump. Since our systems work with this principle, electricity consumption is zero.