Remember that you don’t need to have Bluetooth or AirPort on if you’re not using them--they use electricity, and it’s a snap to turn either one off by clicking its icon in the menubar and selecting Turn Bluetooth (or AirPort) Off.

Don’t power it if you’re not using it--that goes for AirPort too.

Putting the display to sleep will save more energy than using a screensaver. Remember that you can add a layer of security--and keep your Mac from “waking all the way” just because you bumped the desk and jiggled the mouse a little--by requiring a password to return from sleep or the screensaver in System Preferences>Security.

If you don’t enter your password at the prompt, the Mac just goes back to sleep.

Click the Schedule button in the Energy Saver panel to set a startup/wake-up time and sleep/shutdown time so your Mac isn’t on all night long. If you do find yourself burning the midnight oil, just click Cancel when the shutdown dialog pops up at your prescheduled zero hour.


The scheduler could use a little more flexibility, like different settings for different days.

Advanced Greenery: Hacking Your Footprint

“Preferences?” you say. “Please.” Well, that was just the beginning. Once your Mac is on a power diet, you can start considering everything else you’ve got plugged in, and take a more holistic approach to powering down your power usage. Here’s how:

Thousands of sites can give you greening advice, but we dig WattzOn.com. You answer some questions about your life and your stuff (from cars and TVs down to your books and iPod case), and it estimates your total consumption and offers tips to reduce it. A free account lets you save that data, see it in new ways (for instance, it would take a solar panel of more 2,200 square feet to support a typical Mac|Life editor’s personal energy usage of 6,190 Watts), compare it to others’, and more.

Informative, easy-to-use WattzOn is quite illuminating.

Fancy systems can monitor the power usage of your entire house in real time, although they often require professional installation by an electrician. The Energy Detective, or TED ($144.95, www.theenergydetective
.com), displays your current usage on an LCD, so you can see the effects of plugging in or unplugging devices right away. And it can estimate your monthly power bill, so you’re not shocked. The Centameter ($179.99 Canadian, about $144 at press time, www.eco-response.ca) displays your electricity usage and its cost, plus the equivalent greenhouse gas emissions, and you can take the wireless display from room to room.

TED’s real-time energy monitoring lets you experiment with plugging and unplugging electronics for the most savings.

Power strips with timers (popular with people who own fish tanks) are pretty inexpensive--the GE 57698 24-Hour Power Strip Timer is just $19.99 on Amazon. One side has 4 plugs that are always on (for example, we always want power for our TiVo and the router it’s connected to). The other side has 4 plugs on a timer, so we don’t need to remember to turn off the power strip before work each morning, but our TV and stereo won’t suck up standby power all day.

Sleep Deeper

The default sleep function in Mac OS X is known as “hardware suspend mode,” meaning the RAM is still powered on to save the details of your session and allow you to wake the computer quickly.

Apple included Safe Sleep mode in Mac OS 10.4.3 (the feature works on PowerBook G4 and Intel laptops), which still keeps the RAM powered on to remember your session, but also writes the session details to a file on your hard drive. That way, if your laptop’s battery runs out while it’s asleep--which would kill power to the RAM, naturally--the contents of that saved file are transferred back to the RAM when you reconnect the Mac to an outlet and wake it up. It just takes a bit longer to wake up the Mac and restore your session.

Windows machines have a hibernation function too, known as “software suspend mode.” This saves the details of your session to the hard drive, so the computer can shut down totally and consume no power. If your Mac supports Safe Sleep mode (again, any Intel machine and the PowerBook G4, running Mac OS 10.4.3 or later), you can force the Mac to hibernate with the Deep Sleep widget (free, deepsleep.free.fr). It basically puts your Mac into software suspend mode right away, regardless of your remaining battery life, and your Mac won’t use any power at all while it’s hibernating.


The Greenest Mac:

A Reused One

Host your own website. OS X has its own built-in Web server. Instead of paying someone to host your Rick Astley Appreciation Society webpage, plug in your old Mac, enable Web Sharing in the Sharing pref pane, and you’re good to go. Add in some DNS hosting, and you can use your own domain name to point to websites hosted on your Mac.

Ditch CDs for good. Thanks to library sharing built into iTunes, you can easily turn an old Mac into the world’s greatest jukebox. A stereo mini-to-RCA cable is all you’ll need to output sound to your existing home stereo, and you’ll be able to control playback locally on another Mac or remotely with the Remote app for iPhone or iPod touch (free in the App Store). Extra points for setting the old Mac to automatically rip CDs as you insert them, making your new music server fully automated.

An Apple TV that also plays discs. The folks at Apple may not be fans of the optical disc anymore (and ultimately the earth will thank them), but plenty of people still prefer DVDs to digital downloads. An older Mac running Front Row and/or the VLC Media Player (free, www
.videolan.org/vlc) brings you all the features of the Apple TV, with none of the limitations of that box. Play DVDs, drag and drop video and music files across your network, and play tons of formats--not to mention Hulu--that Apple doesn’t support on the Apple TV.

Roll your own file server. Family snapshots, your extensive collection of ’90s grunge albums, tax documents, and every paper you ever wrote in college. You may not need all of that on your Mac all the time, but it’s nice to have it available somewhere. Stash an old Mac and a bunch of unused external drives in your basement, and you’ve basically got a set-it-and-forget-it file server, courtesy of OS X’s File Sharing features.

Share the love. There’s nothing like a free computer to make someone’s day. And we all know at least one person who needs a tech makeover. And since Macs tend to age particularly well—especially for the routine browsing and emailing that most people do—kicking down an older Mac to your sibling or parents is a great way to turn Windows users into Mac-heads.

Dedicated BitTorrent client. BitTorrent is rad. And despite what the RIAA would have you believe, there’s plenty of great free, legal content available via torrents. But it can be a pain to leave your main Mac up and running for the days on end it takes to download giant torrents like the South By Southwest 2009 music sampler. All you need is a BitTorrent client like Transmission (free, www.transmissionbt
.com) or Vuze (free, www.vuze.com) to turn an old Mac into a full-time BitTorrent box. And with some clients, you can easily control your torrents remotely over the Web. Just remember to use our energy-saving tips from earlier in the article to set your System Preferences to use less wattage from the wall.