booting into linux USB: will it increase battery life?

After googling 'cool things to do with a USB jump drive' i stumbled upon the notion of booting from a USB jump drive. At first I thought this would be useless for me as I have a laptop (no need to run linux on a school computer) however, i realised that if I could boot from the USB jump drive my laptop hard drive would not spin up. Knowing that this is an energy intensive process, perhaps booting from USB would save energy by circumventing the energy use of the physical HD for a semi 'solid state' jumpdrive.

I was thinking of booting into linux mint (the potential USB boot OS) during lecture to type a few notes in a rich text format and then boot into windows to copy them out at the library or at home.

To prevent confounding variables from arising i need to know a few things:
1.) Is linux in general good at maximizing battery life? from what i've heard, it does not.
2.) Does booting from a jumpdrive really draw less power than accessing a hard drive?

thanks

edit:
after creating this thread i realized that this might go better in the Linux section!

 

Many claim that Linux is good on laptop battery. I haven't experienced it on any of my comps. Booting from a jump drive would not affect much to the power, the system still check the rest of the devices.

cheers ...

 

1) depends on the machine. Linux doesn't have much manufacturer support for a lot of hardware, so there are a number of things that can waste power that are more efficient under Windows. Notably, it's harder to undervolt on Linux than on Windows.

2) It can. It'll keep the hard drive from being spun up (if you don't mount it). But you will actually find better battery improvements from undervolting your CPU, turning down the brightness, and turning off any wireless devices you don't use (like bluetooth, or the wireless card when you're not actively using them).

 

In my experience,any Linux distro isn't as energy efficient as windows.. I haven't tried booting from a USB drive to conserve power.. but at any rate.. a hard disk hardly takes 2W under max load..

Personally, i stick to Gentoo on the desktop, and Vista,(and now 7), on the laptop.. If I need a linux environment, I just run it in a VM..

 

Just an update:
I have found that linux mint was a resource hog. Instead, i have managed to switch to linux puppy which actually creates a RAM drive. Any modifications are copied to my jumpdrive upon exiting the OS.

I stripped it down to its bones, and i can manage 3:40 hours with wireless off and screen dimmed. This is quite impressive seeing as the processors are not undervolted. In comparison, my vista gets about 3:40 (no wireless, screen dimmed, and undervolted).

These results seem promising IMO.

I might not end up using the USB as a bootloader afterall. However, booting into and out of linux puppy takes about 30 seconds and content access is instantaneous, considering the data is temporarily stored in the RAM.

*As an aside, the battery life is actually estimated by tracking the time it would take for the laptop to use 5% of the battery. I merely extrapolated to get a rough estimate.