Ok... I don't want to be playing silly games with resistors so that out.

I can get a 48V LED in with a 2.7 Ohm 3W resistor but with a maximum current of 1A it will be producing 48W of light! Cooling it isn't an issue as I can use the chassis as a heatsink but 48W of light is insane. However because its so simple its very tempting, I just worry it will put even more strain on the batteries.

If its 1A at 48V the is it drawing 1A/h? If so I can live with that.