AVP's Aura Roof Vents do not move but provide active suction through the inner and outer louver design. They do so by using the Venturi effect. Check out this engineer’s testimonial after purchasing two Aura Vents for his house in southeast Tennessee. After installing them to the roof he immediately noticed the difference.
"I have a ranch style 1800 sq foot house in southeast Tennessee. I wanted to increase the ventilation in my attic. I searched the internet for active roof vents with no moving parts.
I am an engineer and had done quite a bit of research on passive roof vents.
I found the Aura Vents on your website and read about the capabilities to remove hot air from the attic with no electricity or moving parts. The technical reports were quite convincing. I bought two AV-14 vents and had them installed when I re-roofed the house. Right away I could feel the hot air being sucked out of the attic.
I am impressed with the results I have gotten with my Aura-Vents and highly recommend them."
The Aura Ventilator™ uses minimal wind power and no moving parts. The wind enters through a set of exterior vertical louvers. Thus producing the necessary vacuum to extract excess moisture through the second set of louvers. As demonstrated from this view from above, air enters the vent from the front (left side of diagram). Then passing through exterior louvers into the inner chamber, where it circulates and picks up speed. As a result, a vacuum draws up the warm vapors from beneath the vent into the middle section. These vapors enter the inner chamber through the interior louvers. Then circulate together with the air which had entered from outside, until they both forcefully exit through the back of the vent (the right side of the diagram).