This evening I ran some tests on how much current my 2012 15 inch MacBook Pro and my 2012 11.6 inch MacBook Air draw. Both have i7 processors. The Air is dual core and the MBP is a quad core. I tested each unit with the display set to medium, one dot and full brightness. I tested using both a 12 volt to 110 inverter and a third party 12 volt car adaptor. The results are similar but the 12 volt car adapter was more efficient in all cases. Here is a summary of the results:

I was very surprised to see that the MacBook Pro was very close to the same amperage as the MacBook Air when performing light duty tasks. I don’t have a good way to measure the systems under load but I get the impression that the Pro could really crank up the current draw if it was doing something processor intensive. Another note I made is that the Air will occasionally drop down to less than an amp draw, the Pro never dropped below 1.5 amps.

Maybe I will measure the current draw while streaming video when I have time.