An exhaust fan pulls the smoke in one place without a duct. This allows the smoke to interact with other kitchen elements.

In case of the Kitchen chimney the smoke is sucked into a duct directly above the hob/stove and does not interact with any other kitchen components.

Average Power Consumption

Exhaust Fan -80 Watt

Kitchen chimney - 200 Watt

Average noise

Exhaust Fan -40dB

Kitchen chimney - 58dB