Montunoman,
One option is a Yamaha PSR-EW410 which can take aC aadapter or D size batteries and also rechargeabel batteries too.
It is about 18lb plus . It is also a 76 key keyboard for the players out there who want a little more room.
758 (237 Panel Voices + 24 Drum/SFX kits + 40 Arpeggio + 457 XGlite voices)
Featured Voices 1 Live! Voice, 8 Sweet! Voices, 3 Cool! Voices, 3 Dynamic Voices
Also it has a USB connector for storage too.


Allan