Laptop Battery life

[Sashin]

Has anyone noticed that Ubuntu's battery life is nothing compared to Vista's. I've bought a laptop, called the Acer timeline which advertises more than 8 hours of battery life, but all I can get is 3 and a half.

All of the articles I've read about extending battery life involve sacrificing something important such as usb automount, cd rom polling or enabling usb auto suspend. Does anyone know of a better way to significantly increase battery life as powertop only gives me one thing and less watts is confusing.

[winjeel]

I don't think it's that simple. If you use peripherals like a mouse, an external hard drive, wifi, and such, and also if you work continuously, and considering the monitor takes a lot of juice, then 3.5 hours sounds good to me. The other question is, how do they measure "8 hours". To me that sounds totally amazing, and unbelievable. I guess, if you turned on a computer with a brand new 6 cell battery, and left it running with the screen turned off, then it will maintain power for 8 hours, I'm sure. Oh, and one more thing matters, assuming it's not too cold, too.

[Sashin]

It was over four hours before I got wireless internet. And I use a mouse. But I'm not sure how to get it any higher.

According to reviews, claim of 8 hours is no exaggeration, I'm just hoping I can get it to at least 5+ under ubuntu but don't know how.

[Sashin]

The default battery thing says 3 hours 50 minutes, powertop gives me five hours and the gnome panel applet gives me 5 hours 3 minutes which is more accurate?

[winjeel]

My feeling is, a computer with Vista, that's been used for about one year, loaded with a lot of programs that are doing nothing, but are running anyway (eg: PhotoShop Elements, iTunes, Apple Sync, Veoh, AVG, etc) , then even with a new battery, you're not going to get the manufacturer's claim of running time. My Windows XP is extraordinarily slow now (despite defrag'ing), and the cooling fan runs overtime, whilst Ubuntu on mine runs quickly, and the fan doesn't seem to need to run constantly (I hope that isn't an indication of a problem).

Companies tend to exaggerate. Go now, and double check the connection speed of the internet you're paying for now, then check what your real connection speed is here. And then repeat that test in quiet and busy periods for a few days. I bet you'll never achieve what your provider claims.

[ddrichardson]

Is frequency scaling enabled?

[DeadSuperHero]

Try installing the package "cpufrequtils", I found it definitely extended my battery life by an hour.

[twright]

Well if you want the longest possible battery life then it is well worth sacrificing stuff like automount, CD autopolling and brightness. You could also try running less whilst on battery. You could also try setting the CPU scaling to powersave whilst on battery.

There are however no miracle solutions otherwise they would have been done by default - Ubuntu's power efficiency is getting better each version and there are some useful features coming up in Karmic which should improve things.

edit: I can usual get 4-5 hours on my eeepc which also promised about 8 hours; I have never ran Windows on it so I do not know how they compare but it is usually long enough for me.

[Sashin]

I get about the claims, of "just under a meg a second". With internet, but most reviews say something like "for once acer isn't exaggerating" etc.

I've probably enabled CPU scaling, I applied some of the things from Lesswatts using a thread on the dell MPS. But it doesn't seem to have made a difference.

I think the estimate could be wrong. I read somewhere that I have to let my battery fully discharge and charge before it reads properly. The battery applet and powertop give different numbers. About 5 hours when idle but only 3 hours when running a few apps. I don't know which one of them or if any of them is accurate.

[twright]

I get about the claims, of "just under a meg a second". With internet, but most reviews say something like "for once acer isn't exaggerating" etc.

I've probably enabled CPU scaling, I applied some of the things from Lesswatts using a thread on the dell MPS. But it doesn't seem to have made a difference.

I think the estimate could be wrong. I read somewhere that I have to let my battery fully discharge and charge before it reads properly. The battery applet and powertop give different numbers. About 5 hours when idle but only 3 hours when running a few apps. I don't know which one of them or if any of them is accurate.

How many watts does Powertop say your computer is using? (usually I would expect it to be the most accurate but both are based on estimation). Mine hovers at around 11-12 when on battery.