Originally Posted by
tentseller
The problem is standardization. People cannot agree on a standard current to supply. Equipment cannot agree on a stand input current or power plug.
How come it is possible in the automobile: 12V DC socket.
Uh, the two standard airline-use plugs USE the same 12-15VDC that cars do. One uses the same PHYSICAL plug that cars do (used on American Airlines, possibly others) the other uses an "Empower Plug" with the same current/voltage requirements but two non-coaxial pins in a round plastic shell.
The other "standard" is the international 115VAC - Cathay Pacific, among other airlines, has outlets at every seat even in coach on their new long-haul product.
They're capped at a fairly low wattage (75?), roughly the same as the car-outlet and empower ones.