Strategies for maximizing a Laptop’s battery life

Have you ever run out of battery power on your mobile PC during a meeting or a class? Have you worried about running out of power while waiting to meet with a client? Have you asked yourself how much longer your battery will last? Sufficient battery life is a persistent challenge for mobile PC users.

Hardware aspects of power saving

From Ask-leo’s article on maximizing Battery life, Leo brings out some interesting points along with Jerry Foutz of SMPS Technology. His article states that the single most important aspect to maximizing battery life is matching the battery to its charger. About the only way you can maximize the probability of this happening is to buy both from the computer manufacturer for the exact computer model. Apparently even small differences in output voltage of the charger can have dramatic impact on the lifespan of your battery, by either under, or over-charging.

Again, from Leo’s article, another factor in battery life? Temperature. If you look at the bottom of your laptop you’ll see it probably has feet (or more likely, bumps or rubber pads) that lift it off of any flat surface you might put it on. That creates very important space for ventilation. If you block that space, with say your lap, it’s likely that you’ll be causing the laptop to run hotter than it should. If you do this regularly, you’ll likely shorten the lifespan of the laptop’s batteries.

Myth or Fact: Running a Laptop 24/7 would reduce my battery’s life. Again, to quote from Leo’s article, “If your computer is always on and in use, the battery temperature may sit in an environment of 30C (86F) and drop to 65% capacity in a year. If it reaches 40C (140F) you can drop to 60% capacity in only three months! You get the idea why keeping your battery cool is so important. From the battery perspective, removing the battery while on AC power would reduce its temperature and help battery life, but from a power supply designer’s perspective, this is not recommended. The presence of the battery provides substantial design margin to your laptop as well as protecting it from power surges and sags.”

In this article, I’ll discuss how to take advantage of Windows settings to manage power more efficiently. I’ll also introduce some non-software related tips that you can use to extend battery life.

Optimize Your Power Settings

The display and the hard disk on your Laptop are the two biggest consumers of battery power. By making use of your Laptop’s power-management software, you can squeeze out a lot of extra minutes out of your batery. If your laptop did not come with a customizable power console program, Windows provides a number of power schemes, which are predefined collections of settings designed for different environments and circumstances.

Windows includes two power schemes that were created specifically for Laptops.

The Portable/Laptop power scheme minimizes the use of power to conserve your battery, but adjusts to your processing needs so that the system speed is not sacrificed.
The Max Battery power scheme minimizes power use but does not adjust as your processing demands change. You should use Max Battery only in situations that require minimal processing, such as reading documents and taking notes in a meeting.

To use a power scheme designed to maximize battery life:

1. Click Start, and then click Control Panel.

You can also create a custom power scheme to suit your specific needs. You can create as many custom power schemes as you want.

Dimmer is better

As mentioned earlier, a big drain on a Laptop’s battery is its LCD screen. Reducing the screen’s brightness conserves battery life. Most Laptops come with an easy-to-access keystroke sequence, function(Fn)key, or software utility for adjusting the brightness. If you think a dim screen is good for battery life, a blank one is even better. Use the above mentioned power management schemes to tell your laptop how long to wait before blanking the screen. However, don’t push it too far too like set the interval to the shortest option of ‘After 1 min’. It will most likely drive you nuts. Find the setting that works the best for you

Take Advantage of Low-Power States

Windows provides two battery-saving sleep states: standby (which is like snoozing) and hibernation (which is like deep sleep).

Standby

In standby, your display and hard disk turn off, and all open programs and files are saved in random access memory (RAM)—your computer’s temporary memory—rather than to the hard disk. Information stored in RAM is cleared when the computer turns off, so it’s a good idea to save your work before placing your system in standby mode. Otherwise, you may lose data if you lose power, you swap batteries, or your system crashes.

Standby is particularly useful when you’re using your mobile PC intermittently during the day. For example, when driving between clients’ offices during the day, put your computer on Standby to maximize the life of your battery and maintain quick access to open programs, files, and documents.

In standby, your battery consumes only a small amount of power. When you want to use your computer again, it wakes up quickly, and your desktop is restored exactly as you left it.

To put your computer on standby:

1. Click Start, and then click Control Panel.

Hibernation

In hibernation, your computer saves everything to your hard disk and then shuts down. When you restart the computer, your desktop is restored exactly as you left it. Hibernation uses less power than standby, but it takes a bit longer to resume.

To manually put your computer in hibernation:

1. Click Start, and then click Control Panel.

Turn Off Wireless

Another significant drain on your battery power is your wireless card. You should turn off your wireless device when you’re using your mobile PC but are not connected to a wireless network. You can either remove your Wi-Fi card or press the manual hardware button on your computer if you’re using a Centrino-based mobile PC. Refer to the instructions from your mobile PC manufacturer to learn where the manual hardware button is.

Additional Power Saving Tips

In addition to adjusting power settings to maximize battery life, consider the following tips to minimize power consumption when you’re away from electrical outlets.

Turn off scheduled tasks. If you use scheduled tasks to run programs or scripts, or if you schedule other tasks to occur automatically at a preset time, specify that these tasks won’t be performed when the computer is running on battery power.
Keep the use of tools in the notification bar to a minimum. Try to minimize your CPU’s usage. Look at the notification area of the taskbar and close any tools (or utilities) that are not necessary. Often, these tools are installed on the computer when you first receive it. The notification bar, shown below, is on the bottom right of your computer desktop.
Disable devices you don’t need. For instance, if you’re on a long flight, you probably won’t use your modem, your network card, your parallel and serial ports, and possibly your DVD or CD-ROM drive. You can easily disable all of these in Device Manager. To open Device Manager in Windows 98 and Me, right-click My Computer and choose Properties, Device Manager. In Windows 2000 and XP, right-click My Computer and select Properties, Hardware, Device Manager. To disable a device, right-click its listing under the appropriate category and choose Disable
Limit power-intensive activities. Avoid watching a DVD or playing online games on your mobile PC when you need to conserve battery power.
Add memory. You can minimize the reliance of Windows on virtual memory and reduce power consumption by adding memory to your mobile PC.
Carry at least one spare battery. Buying an extra battery is a good investment for your peace of mind. Battery prices vary widely. You can significantly increase the power available to you if you’re willing to splurge a little. Contact the manufacturer of your mobile PC to find a replacement battery.
Charge your battery often. When you’re on the road, be sure to carry a power cord and plug your computer in whenever you have the chance.
Completely drain nickel-based batteries. If you’re using an older laptop (at least 3 years old) with a nickel hydride battery, be sure to completely drain it and recharge it monthly to ensure that it will hold its charge. Most newer mobile PCs use lithium ion batteries, which don’t need to be drained to maximize their capacity.

By adjusting your mobile PC settings to conserve battery power and by implementing these tips, you can relieve the stress and inconvenience of running out of battery power.