I require a component, similar in size & shape to a PC cooling fan. 3" x 3" Approx.
That allows current to pass through only when the fan blades are rotating.
The fan blades ideally to be made is plastic, low resistance for low air flow situations.
As light weight as possible, and low cost per unit.
I am building a prototype at this stage but will require future volume.
The best description would be a Airflow switch.
I would also consider a similar sized item that generates a small current when airflow is detected.
Ideally around 5v.