A:Answer Hi there, this is Kelly with Dyson. You can use this on a porch, as long as the Dyson is not exposed to any water or other weather elements. If the porch is open, or screened-in, you wouldn't get the benefit of the air purification. The unit won't cool like an AC unit, as it's just a fan that does not have any Freon.
Best wishes,
Kelly
Dyson Customer Support