A 0.000000000000000000000000000000000000000000000000000000000000000000000000000001 watt LED will drain the vehicle's electrical system, given enough time. Please specify more //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif
I assume this question is more along the lines of "How much power can I run without needing to upgrade my electrical"
For that we'd still have to know what your electrical consists of now, but without ANY upgrades, I wouldn't go much above 600-800, if you upgrade your batt, do the big 3, add another batt, or even upgrade your alt that would change.