Send electronic ticket together with general flight information when sending e-mails to customers. This will cut the sent e-mail number and reduse server energy usage.

Taxiing from and to gates from runways should be more smooth and with less fuel - using for example AI

Incentivize sustainable behavior, e.g. a small reward for bringing your own coffee cup. This can also be sold by SAS in the Eurobonus store or in flight.

At check-in and at kiosk ask if they really need paper boarding card or can use SAS app instead.

Long-haul flights to start descent 3-4 hours before touchdown.

Almost all passengers have their own phones/pads these days. Keep them connected with *good* wifi and IFE wont be needed, massive weight savings.