Testing high electrical use vs. Mpg

[phh]

My vacuum gauge drops 2-3 in/Hg when headlights are turned on. I'm in the process of converting to LED marker and driving lights.

Regarding the electric PS pump, does it pump more when you slow down (in other words, is it speed sensitive?)

[aardvarcus]

I got 0.05 g/h idle difference in my Celica between having my Low Beams on and off. Converting ethanolized gasoline to electricity that is the equivalent of 1,639 Watts per hour. All that power is just to run 70W worth of lights, so the whole system is 4.3% efficient, ignoring the efficiency of the bulbs to create photons. Makes me wonder about permanent magnet alternators.