Yes, but they aren't mentioning that, and I suppose this is quite an important ommission. And btw, valves would create additional drag and reduce efficiency of the device.
- What are the details of the system inside?
Sorry, we do not comment on the details of the inside of our INVELOX system because they are part of our trade secret.
So it is not unreasonable to assume that they have something in there. And they could be needing the valve anyway to close the tube if the wind is too strong to protect the turbine.
There's a paper published by sheerwind, detailing the principles of operation - http://sheerwind.com/wp-content/uploads/sheerwind/2012/10/Al....
There's no mention of any valves, too. But there's a more interesting claim they make: "(...) INVELOX captures the wind kinetic energy
and uses the pressure differentials to increase the kinetic energy
available to a turbine". I wonder how they manage to increase the kinetic energy of air flow without any external energy source.
The more I read about it the more I get the feeling that their goal is to get as much funding as possible without letting anyone test it, kind of like Andrea Rossi and his cold fusion reactor.
