Lowest Power Usage for Internet Connection (BT/Wifi/USB Tether) ?!!

[musicpenguy]

I am wondering if anyone knows out of these three ways of connecting to the internet which uses the least power on the Macbook Air. - I am going to be traveling some and it would be handy to know.

1. Airport Access (Wireless)
2. Bluetooth - iPhone Tether
3. USB Tether - from iPhone

Power for the iPhone is not an issue since I have an external battery.

What do you guys think!!?

[allmIne]

I am wondering if anyone knows out of these three ways of connecting to the internet which uses the least power on the Macbook Air. - I am going to be traveling some and it would be handy to know.

1. Airport Access (Wireless)
2. Bluetooth - iPhone Tether
3. USB Tether - from iPhone

Power for the iPhone is not an issue since I have an external battery.

What do you guys think!!?

I'd imagine bluetooth would be the lowest. Airport drains the battery like nobody's business, and if you've got an external battery, there's no point using USB, since that'll drain the battery to charge the phone while you're using the internet.

Course, if you need to charge the phone anyway at some point then you could kill two birds with one stone and use the internet while you're doing it, until it's fully charged, then use bluetooth.

Your best bet would be to bring a wall adaptor for your iphone, probably.

[Mactagonist]

I'd imagine bluetooth would be the lowest. Airport drains the battery like nobody's business, and if you've got an external battery, there's no point using USB, since that'll drain the battery to charge the phone while you're using the internet.

Course, if you need to charge the phone anyway at some point then you could kill two birds with one stone and use the internet while you're doing it, until it's fully charged, then use bluetooth.

Your best bet would be to bring a wall adaptor for your iphone, probably.

Modern wifi chipsets use very very little power. I wouldn't be surprised if wifi was actually the most power efficient.

[musicpenguy]

What are your thoughts on BT vs USB tether as far as power?

[musicpenguy]

Instead of just guessing and whatnot I ran some tests.

I unplugged the MBA running just Safari with BT turned off during the WIFI test and Airport turned off during the BT test and BT and Airport turned off during the USB test. (In order of testing)

4:04 - WIFI
4:07 - BT
2:17 - USB
2:53 - USB (Fully Charged iPhone)

So the clear winner is BT/WIFI and USB really sucks the battery dry :) - USB test was done when the iPhone needed charging so I will run another test latter when it is not charging :)