Help understanding LED efficiency and other characteristics

[bluemantra]

Okay, just trying to understand the basics here as I've been venturing into custom light engines. My basic understanding of efficiency is that the a nichia 219b will drain a battery faster than a nichia 219a assuming equivalent settings. Correct? Now my question is does a 3500k drain a battery faster than a 4500k nichia 219b? And does efficiency also correlate to heat production? i.e. 3500k will get hotter than 4500k run at the same settings?

Thanks and sorry if so basic in this forum.