Squeezing the juice

Quick question: How long does your laptop battery last?

Let's assume a couple of things:
1. It's a Li-ion (lithium-ion battery)
2. It's been charged fully.
3. all you're doing is web browsing on Firefox
4. the battery is a regular 6-cell battery
5. the battery is brand-new


If all of the above conditions are met, the battery should be giving you about 4 hours of juice. But let's face it, some of you are probably getting only around 2 hours of usage. And that really sucks when you are on the go, or when the power cut lasts abominably longer than usual.

So how do you push your battery to that 4 hour mark?

1. Keep it cool. Operate the laptop in air-conditioned environment if possible.
The Lithium-ion battery degrades with higher temperature. The best conditions to keep it would be around 10 degrees Celcius. Anything lower than 0 will render it useless, anything above 40 and you're asking for trouble. A handy thing to remember is if you are running the laptop plugged in to AC all the times and the room isn't air-conditioned, it may be wise to remove the battery and keep it somewhere cool. (This may not be such a good thing to do in India where the power supply is shit though.)

Also, lithium-ion batteries degrade with time,as in from the moment it was manufactured. This is something you can't do anything about. It is helpful to know this when purchasing extra batteries.

2. Purchase an extra battery if you really really need it. You'll be happier.
Get a 9-cell battery.

Now comes the more techy parts

3. BEST TIP: Turn down your screen brightness. All the way down to minimum. Also, the smaller your screen, the longer your battery can go.

4. SECOND BEST TIP: Turn off/Disable your wireless and bluetooth. It's better if your laptop has an external switch to actually power off the network card. Otherwise, use Fn+apropriatekey.

5. Stop using your CD/DVD drive. It sucks. Power, I mean. And please do not try to burn a CD or DVD while on battery power. It just isn't going to work out well.

6. Disconnect all external peripherals if possible. Including USB mouse and any drives.

7. If your laptop comes with software to throttle down your power usage, PLEASE fucking USE IT. These programs slow down the processor, down to about 800MHz. Believe it or not, it saves power.

If your manufacturer did not provide such a program, it's actually a good thing. In windows, right-click on the desktop and click Properties. Go to the 2nd tab, and go down to the bottom there to tune your laptop's behaviour. I'd suggest turning off the monitor after 1 minute of idleness, especially if you are just waiting for a file transfer to complete. The rest are up to you.

8. Turn off ALL programs you are not using. Including antivirus/antispyware/firewall if you are not connected to the Internet and not introducing any external drives to the laptop.

9. Having more RAM helps by reducing the amount of read/writes to the hard disk. More the hard disk has to be accessed, more power is used. I'd say 1Gb is the sweet spot these days.

10. Having an Nvidia/ATI GPU means you're screwed. Extra power usage.

11. Having a UPS for a laptop is as good as having a secondary battery, especially when combined with the above changes. If you can drop the power drain low enough, the UPS can be squeezed for 1 hour's worth of juice.



LINUX BONUS

1. The above instructions apply.

2. Linux inherently saves more power on laptops, simply because of the lower drain on the system, in addition to superb processor throttling.

3. Log out of Gnome/KDE and use one of the 6 terminals. Command-line programs ftw.

4. Use Intel's Powertop, if you are using an Intel processor, to detect which program(s) is causing the most number of processor interrupts. These interrupts increase power usage. Powertop also makes some very useful suggestions to further decrease power usage.