It's not "just like the A/C". Electrical drain, does not put a strain on your engine, only your electrical system. An A/C compressor works with a clutch on the compressor housing that engages and disengages as necessary to keep the accumulator charged and blowing cold. Each time it engages, it puts a strain on your engine, thus robbing it power, and in turn...fuel economy. Your electrical is regulated by...you guessed it, a voltage regulator. This has no moving parts, like most electrical devices on a vehicle...and does not inhibit gas mileage. Your alternator spins and creates the same amount of drag regardless of if your voltage regulator is requiring power or not to the system. Unlike an A/C compressor as mentioned above...your alternator does not cycle on and off. You will not lose gas mileage because of adding electrical devices, especially not a power inverter...
· 1 decade ago