Problem You want to extend the battery life of your laptop so that you can use it longer between recharges, for example on a cross-country plane flight. Solution Using a graphical user interface If you have a wireless network adapter and you're not using it, turn it off by right-clicking on its icon in the Notification Area and choosing Disable. Wireless and wired adapters can use a substantial amount of power disabling yours could save you up to 20 minutes of battery life. If the wireless network adapter isn't built into your laptop but instead is a PC card, take the PC card out of the laptop. Lower the backlighting on your screen. Your screen takes up a substantial amount of electricity, and it most likely doesn't need to be lit up to its brightest level. Check your system documentation for how to change the lighting level. Use the right power scheme. XP includes a number of preset power schemes that you can use for various purposes. The schemes differ according to how long it takes for XP to shut off power to the monitor and hard disk when there is no system activity, or when the laptop should go into system standby. In system standby, power is cut to the hardware components you're not using, such as your monitor and your hard drive, but power is still supplied to your computer's memory so you don't lose your work. Get to the power schemes by choosing Control Panel Performance and Maintenance Power Options. For maximum battery life, choose Max Battery from the Power schemes drop-down list. Low Power Mode and Portable/Laptop are also good choices, although they don't preserve as much power as Max Battery. After you have selected your power scheme, click OK. Remove unused PCMCIA cards from your laptop, because they can use substantial amounts of power. Disconnect external drives, especially those that are USB-powered. External drives get power from your laptop and can be electricity hogs. Increase your RAM and decrease your swap file space to limit disk accesses. The fewer times you access your hard disk, the less power you'll use. Disable sounds. Each time a .wav file plays, you're using up juice unnecessarily.
Discussion Take care when using laptop batteries that you fully discharge them before recharging them. Batteries have a "memory," so if you frequently use only half their power before recharging them, for example, you'll cut the amount of power that the battery retains. There is at least one instance where trying to save power can interfere with the functioning of your PC. If you're using WiFi, don't use its power management feature, if it has one. You can lose your connection going into standby, and if you use EAP or other authentication methods, especially with separate secureID/cryptography devices, reconnecting can be very difficult. See Also For information about how to extend battery life by using standby and hibernate, see http://www.microsoft.com/windows2000/techenthusiast/features/standby1127.asp. Many airplanes that make transcontinental flights have an Empower port, which can be used to power a laptop. You'll have to use a special adapter to connect your laptop to an Empower port. You can buy separate special adapters, or can instead buy a universal adapter that connects to Empower ports, AC power, and other power sources. Targus, among other hardware manufacturers, makes such a device. |
