extending battery-life on a macbook or in general

[Hagen Kaiser]

Hello everyone,

My Systems is a Macbook and Ubuntu Edgy.
I experience in MacOS with a fully charged battery a lifetime of about 4
to 5 hours, but with Ubuntu there is a maximum of three hours.
Does somone have a clue what MacOS does that it is able to safe so much
power?
What can be done in general to extend battery-life?
Ubuntu uses powernowd as far as I know. 
setting the mode to passive didnt give anything.

I heard about the possibilitiy to set "a gouvernor" (?) in the kernel
with somthing like 
echoing  to /dev/cpu0/...
but also with sudo there is no way to get permission to echo into there.
(Maybe do I have to boot from LiveCD to that?)

I already turned down screen light to 50%

But isnt there something that could be done beside of speedstepping and
screendarkening? maybe switching off the harddrive (howto do that?) 

Again: Does someone at least have a theory about how MacOS does achive
its battery lifetime? Could we implement something similiar?

And secoundly there is the stand-by mode in MacOS.
I can close my macbook for several days and make it return immediately
experiencing nearly no power loss.
I couldnt make my macbook return from standby till now so i couldnt test
it. Just wanted to ask if standby in linux is able to do the same.

greetings
	Hagen