Washington- Energy prices continue to go up, as does concern over how much electricity computers use. Given that computers continue to become more powerful - and demand more power - it's no wonder that folks are interested in learning how they can conserve energy while still getting the most from their PCs. Read on for some answers.

Q: I'm going to buy a new computer. What should I look out for if I want the most energy-efficient model?

A: The most energy-efficient PC will be a notebook computer. The parts in a notebook are designed with energy savings in mind, and generally a notebook will consume just half the energy that a desktop will, sometimes significantly less, depending upon the configuration of each machine.

Notebooks often come configured for maximum power savings by default, too, usually because they're designed with an eye toward usage on the road, while on battery power.

You can also configure a desktop to use less energy, though. Use your operating system's power saving control panel to decrease the time before a dormant system goes into low-power or sleep mode. Turn your monitor off when it's not in use.

Also, attach your computer and all peripherals to a switched power strip so that you can cut power to everything at once by simply pressing one button. Even in sleep mode, your computer and peripherals continue to draw energy, so cutting off all energy via a power strip makes sense.

Q: I'm still using an old 21-inch CRT monitor. How much energy can I save if I switch to an LCD?

A: Figures from the Renewable Energy Network (EREN), part of the US Department of Energy, show that a cathode ray tube monitor of that size generally consumes around 150 watts of electricity, while a similarly-sized LCD typically uses about 50. What's more, the "sleep" mode of each type of monitor can differ dramatically. A CRT might use as much as 30 watts of electricity even in sleep mode, but an LCD can cut that usage down to under 4 watts.

The amount of time you use your monitor - and leave it turned on - can, of course, greatly effect how much energy you can save. But the EREN points out that under the general energy usage figures listed above, if you use your monitor 6.5 hours per day, you could cut the amount you spend powering your monitor by more than two-thirds.

Keep in mind that these are general statistics and do not apply to all CRTs or LCDs. These days, LCD monitors continue to get bigger, and the bigger they are, the more electricity they consume. So check the wattage ratings on an LCD before you buy if you're concerned about how energy-efficient it is. And remember to turn your monitor off during extended periods of nonuse.

Q: When plugged in, does a notebook computer draw more energy if the battery is left in it?

A: Yes, although the rate at which power is used will depend upon how much of a charge your battery has. Even when turned off, if your notebook is charging a dead battery, it will generally consume about 60 watts of power. If you take the battery out, power consumption of a notebook computer that's in sleep mode will fall to about 1 watt.

The lesson is clear: if you want to wring the most energy efficiency out of your notebook computer, take the battery out when it's plugged in. Doing so has a side benefit, as well. Certain types of batteries will wear out faster if they undergo the constant recharging that occurs each time you plug your notebook into an electrical outlet. So by removing the battery, you'll both save electricity and extend the life of the batter itself.

--- Have a computer question? Send it to the Computer Helper at jayd@csi.com. (dpa)