It could be useful for low-grade thermal applications -- heating (or pre-heating) hot-water supplies, or space heat.
Even simply ducting warm air to street level for outdoor dining (in winter), presuming (against other information, I'm aware) that the ducting could be provided. If you're wasting the heat anyway, put it to some use prior to final venting.
Even simply ducting warm air to street level for outdoor dining (in winter), presuming (against other information, I'm aware) that the ducting could be provided. If you're wasting the heat anyway, put it to some use prior to final venting.