TLDR: is it possible to get a motorised exhaust vent cowling for a rangehood - i.e. actuated to force open and closed when the rangehood is on and off.

I need to replace our rangehood. The stovetop is on a south facing wall, and while it's not the prevailing wind, in a southerly storm the house (and that wall in particular) takes a bit of a beating. I can only assume this is why the existing rangehood (predating our ownership) has a good 20 meters of ducting snaking through the ceiling cavity to a rooftop mushroom-style exhaust. I've had a poke around, and the ducting is thoroughly coated in fat and other unpleasantness. I'm not surprised that a rangehood fan does't put out enough pressure to actually vent out that length of ducting. To make this system work, I think I would need to replace it with more robust ducting and an inline booster fan in the ceiling space.

I'm thinking it would likely be much better just to vent the rangehood straight through the outside wall, but really want to avoid either louvres banging in the wind or other basic solutions that let a howling southerly into the kitchen. I'm fine not to use the rangehood while a southerly is raging.

My google-fu has failed me. "Motorised louvres" seems to produce results for patio louvres. Does a mechanical type of exhaust vent cowling/louvre exist? I'm happy to pay for professional advice if anyone can recommend someone in Wellington