Updated on 09.17.14

8 Energy Savings Tips For Your Computer

Trent Hamm

It only takes a few small adjustments in your routine to build up some significant energy savings, and one of the best places to start is with your computer. With just a few little tweaks, you can save hundreds of dollars in computer energy use over its lifetime – and these tweaks can go almost entirely unnoticed by the user.

Here are eight great energy savings tips you can try on your own machine. Some of these tips work best for different setups and different types of machines – not all of them will apply to every system. Choose the ones that work for you and give them a whirl – you might just find yourself not noticing a different at all except for the lower energy bill.

strip1. Plug all equipment into a SmartStrip.
In most home situations, computers are used for a bit of web surfing, gaming, and other miscellaneous work in the evenings for a bit. This often requires the use of a lot of peripherals – everyone flips on their monitor, and most people turn on their printer, their speakers, and so forth. Then, at the end of the evening, they shut things down, but leave all of that other equipment on, sitting idle, just draining electricity. A printer and speakers left idle can easily drain 40 watts.

Thus, most home computer users are well-advised to install a SmartStrip for their home computer setup. A SmartStrip allows you to plug your computer into the “master” outlet and several other devices into the other slots on the strip. Then, whenever the computer is on, the other outlets receive energy – but when the computer is shut off, the power to the other devices is automatically shut off. Thus, when you turn off your computer in the evening, the power is cut to the monitor, the printers, the speakers, the internet router, and anything else that might be a piece of peripheral equipment.

Let’s say your internet router, your printer, and your speakers eat 50 watts just sitting there idle, and having a SmartStrip eliminates that usage an average of 10 hours a day (they’re not sitting on all day when you’re doing other stuff). Over the course of a year, that’s 182.5 kilowatt hours of energy not being used, and with electricity hovering around a dime per kilowatt hour, the strip can save you $18.25 a year, year in and year out.

2. Set up Windows so that it automatically shuts down every night.
Every other night or so, I used to leave my computer on after I went to bed and I wouldn’t notice it until the next evening after I got home from work. That is, until I told it to shut down automatically at two in the morning each night. Here’s how to do it on a Windows PC (it’s really easy):

1. Click Start, and then click Control Panel.
2. Click Performance and Maintenance, and then click Scheduled Tasks.
3. Double-click Add Scheduled Task. The Scheduled Task Wizard starts.
4. Click Next.
5. Under Click the program you want Windows to run, click Browse.
6. In the Select Program to Schedule dialog box, locate the C:\WINDOWS\System32 folder, locate and click the Shutdown.exe file, and then click Open.
7. Under Perform this task, specify a name for the task and how frequently you want this task to run, and then click Next.
8. Under Select the time and day you want this task to start, specify a start time and date for the task, and then click Next.
9. Type the user name and password to run this task under, and then click Next, and then click Finish.
10. In the Scheduled Tasks window, right click on your new task and choose Properties. Select the Settings tab, then check the box that says “Wake the computer to run this task,” then click OK.

That’s it. It’s done. So what do you get out of that? Let’s say your computer uses 80 watts per hour, and your monitor when receiving no signal eats 5 watts an hour (these are rough average estimates). So, every hour your computer is off when it would have just been sitting idle saves 75 watts or so. Now, let’s say that every other night, you forget to turn off your computer and you don’t notice it until you come home from work the next day. That’s about 20 hours of unused energy, or an average of 10 hours a day. Over a year, that’s 3650 hours unused – a lot of time.

Multiplying 3650 hours by 75 watts gets you a big number, about 273.75 kilowatt-hours. An average eletric bill charges about $0.10 per kilowatt-hour, so multiplying $0.10 by 273.75 gets you the amount of money you put right in your pocket just for doing this simple task once and forgetting about it. Thus, over a given year, this tactic can save you about $27.

Even better, this tactic combines very well with a SmartStrip as described in the first tip. If your computer automatically shuts down at 2 AM, so will everything else plugged into the SmartStrip.

3. Tinker with your computer’s energy settings.
Almost all modern computers (Windows XP and Vista and Mac OS X) have a control panel that allows you to set various energy saving options, such as how long before the computer and the display go to sleep during inactivity. Play with these settings and try to find the lowest numbers that are still convenient for your use.

For example, I set all of my settings to an hour (lower than what the defaults were) and found they didn’t bother me at all. So I kept lowering them. Now, my screen saver pops on after three minutes and everything else goes to sleep after five – I’ve found that if I’m away longer than that, I’m usually away for quite a while. A wiggle of the mouse wakes it up, so it’s no big deal.

This can save a ton of energy over the long haul. Let’s say the energy use of my system drops 60 watts when it goes into sleep mode. If these settings cause it to spend two more hours a day in sleep mode, that’s 43.8 kilowatt hours, an automatic savings of $4.38 in a year.

4. Use an efficient uninterruptible power supply, especially for computers you don’t turn off.
I almost never turn off my work computer. To protect it, I use a “green” uninterruptible power supply for it and most of the peripherals.

This has three benefits. First of all, a good universal power supply regulates the energy use of all of the devices plugged into it, minimizing the energy wasted from “switching” from device to device. Using a Kill-A-Watt energy tester, I found that the unit I use uses about five fewer watts than an ordinary power strip with the same devices plugged into it. That’s a non-stop around the clock savings of about 43.8 kilowatts per year, or $4.38.

Second, it also functions like a SmartStrip, with a master outlet and several slaves. I turn my workstation off only for long trips, and the power supply automatically cuts power to my monitor, my printer, my speakers, my external hard drive, and my internet router. All told, these devices use about 100 watts of energy on average, and the strip eliminates about seven days of use for these devices a year. This adds up to 16.8 kilowatt hours per year, or $1.68.

Third, since there’s a battery back-up inside the unit and also surge protection, I’m protected against power surges and short-term power losses. While this is difficult to calculate directly into dollars, if we experience two power losses per year and two significant surges and this device protects my equipment and keeps me from losing data, it’s well worth the investment.

5. Remove all unnecessary peripherals from home servers.
Our home has a shared file server that we all use. It was an older PC that got “recycled” into a new use, but later, when I checked it out with my Kill-A-Watt energy usage meter, I realized it was sucking down a lot of juice. When I investigated further, I realized that there were a lot of things inside the unit that weren’t really necessary.

Thus, I simply removed an old graphics accelerator card, an old DVD-R drive, and an old CD-RW drive from it and observed that the energy use of the unit went down about seven watts. Over the course of a year, since this machine would be in use nonstop, that choice eliminated 62 kilowatt hours of usage, saving me $6.20 per year. Since the server is on a monitor and keyboard switch and is only used for, well, file serving, I also don’t need that equipment for it, either.

laptop6. Put your laptop charger (and other chargers) on a timer.
Around our house, you can find a handful of outlet timers that serve one purpose and one purpose alone – to make sure devices come on for only a portion of the day when they’re needed.

For me, I tend to use my laptop about once a week. The rest of the time, I usually leave it on the charger and forget about it, but that presents two separate problems. First, leaving it on the charger degrades the battery over time. Second, leaving the charger plugged into the wall – with that big old converter box on it – eats energy at a pretty rapid rate. It eats about 50 watts per hour, according to my measurements.

Thus, I just leave the laptop plugged into the charger all the time when not in use, but the charger is plugged into an outlet timer. That outlet timer comes on from midnight until two in the morning, just long enough to make sure the laptop refuels. If I need it on during the day for some reason, I just reach over to the outlet and touch a button – it then stays on until two in the morning and returns to that cycle.

That outlet timer is saving me a lot of money. I estimate that on an average day, it eliminates 15 hours of energy use by that charger, as I just tend to leave my chargers on the outlet for my convenience. At 50 watts, that adds up to a savings of 273.75 kilowatt hours per year, an annual cash savings of $27.38.

7. “Green” your equipment when you replace it – go for EnergyStar 4.0 compliant.
When it comes time to replace your equipment, spend a few bucks extra and make sure you get one that uses minimal energy. Do the research and look for equipment that’s EnergyStar 4.0 compliant, as those specifications are very tight on energy use. An EnergyStar 4.0 compliant computer uses about 25% of the energy that a non-EnergyStar machine could potentially use – that’s a huge savings if you’re using the computer over time, one that pays for the few extra dollars you might have to pay right off the bat.

One big point of savings is the move from a CRT to a flat panel. Many homes are slowly making this move, but with the low cost of flat panels and the huge energy savings, the move will save you money over the long run. The average 17″ CRT monitor uses 150 watts while awake and 30 watts while idle, while an IBM T series 17″ flat panel uses 50 watts while awake and 3.5 watts while asleep on average.

Let’s say, then, that on an average day, your monitor is awake five hours and asleep two hours. The flat panel will save you 553 watt-hours during that day. Over the course of a year, that’s 201.84 kilowatt hours, or a savings of $20.18. I calculated my own usage, and on an average day, my monitor is awake for nine hours and asleep for three. That adds up to 357.52 kilowatt hours over the year, or $35.75. Given the low price of smaller flat panel monitors, it doesn’t take long – just a few years – for the energy savings to pay for the switch.

8. Adjust your monitor’s brightness.
One subtle move you can make is adjusting your monitor’s brightness by playing with the levels until you find the minimal acceptable brightness for your work. The Saving Energy blog found that reducing a flat panel monitor’s brightness from 100 to 0 shaved 12 watts off of the energy use, with an almost identical reduction with CRT monitors.

My monitor, by default, had brightness set at 80, so I started playing around with it until I found a brightness level that worked for me – 25 (this took a lot of experimentation over a number of days). Assuming this relationship is correct, this saves me 7 watts per active hour of use. If I use my monitor nine hours a day with this new setting, I’m saving 23 kilowatt hours each year, or $2.30 per year, for an adjustment I’m completely comfortable with. Even a reduction in brightness of 8, which would save 1 watt, would save 3.285 kilowatt hours per year, or $0.33.

These really add up.
Using these adjustments (at least, the ones that applied best to my situation), I spent about $100 on equipment but shaved about $70 per year of electrical use off of my computer. Over five years, that’s a net gain of $250 – and it’s for changes I basically don’t notice.

How green is it? That $350 in energy savings represents 3,500 kilowatt-hours. Each kilowatt-hour, on average, produces about 2 pounds of CO2 (averaging the numbers I found from a pile of different sources). Thus, these moves not only saved me a net of $350, it also prevented three and a half tons of CO2 emissions. That’s change I can definitely appreciate.

Bonus Tip: Read a book.
For those of you who get most of your information online, why not take a night or two a week, leave the computer off, and instead read a book? You can check one out for free at your local library and there’s absolutely no energy use involved other than a light bulb over your head (which you’d likely have on anyway). There are so many amazing fiction and nonfiction works out there that there’s guaranteed to be something out there that will engross your mind. Take advantage of it. If you can’t think of anything else to read, try The Wind-Up Bird Chronicle by Haruki Murakami – it’s sublime, fun, and will make you think.

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  1. L says:

    Just remember to save your work periodically if you do #2 and like to do late night computer sessions!

  2. Those are some great suggestions for saving energy and money. I would have never realized until I read this post on how much you could actually save. I think alot people take these smaller steps for granted as they don’t realize the impact it can create.

  3. Trent,

    I love your idea in #6. I already have a few timers from Christmas lights. I need to play around with my Kill-a-Watt some more and see what kind of wattage is being pulled from my cell charger (never used during the daylight hours on weekdays), etc.

  4. Kevin says:

    Trent, look into wake on lan for the server. If all it does is occasionally serve up files. This may save you even more electricity by keeping the computer asleep except when you need it to serve up files.

  5. Daniel says:

    I’ve worked in I.T. for years, and I’ve recently been working on my own project (http://theartofzenliving.com) so I spend a LOT of time in front of a computer. One of the tricks I’ve learned is that if I can use several power strips to section out my peripherals. I don’t often use my printer or external HDD, so they are on one strip that only gets turned on when I need to print. My mouse (wireless), LCD and speakers are on another power strip that can be easily turned off if I’m stepping away from the computer but it’s still working on something – that way the computer may still be on and doing it’s thing, but it’s ONLY the computer that’s on, not all the rest of the stuff :)

  6. Becky says:

    I loved The Wind-Up-Bird Chronicle; it’s a fabulous and vividly written book. But there was one chapter that gave me nightmares for a week. If you are impressionable and/or can’t take gore, either read a different book, or skip that chapter when things start getting gross. You will know which one it is when you get there, and you won’t miss much plotwise.

  7. David Moore says:

    Nice article, however, I don’t agree with point 6 regarding battery degradation. 1 full discharge and charge per calendar month is enough to keep the battery spot on and leaving it permanently on charge at all other times is fine.

  8. Jamie says:

    You can get a device similar to the SmartStrip at Menards. I think they are cheaper, too.

  9. Movingonup says:

    These are some great ideas. I am a computer amateur so things like this help.


  10. Joel says:


    For the sake of clarity for anyone trying to do these calculations themselves, you may want to clarify the phrases “watts per hour” (or “watts an hour”) to better reflect the measurements/estimates you are trying to convey (perhaps you mean an hourly average of X-watts?). In most cases, I think you could just say watts…

  11. Addis says:

    I recently bought a SmartStrip (after having read about it in Domino magazine and at TerraPass). I use it for my laptop and peripherals. I plan on buying another one for my TV + home entertainment system, too; I hardly watch TV, yet it’s plugged in and the little red ‘standby’ light is always on!

  12. Andre K says:

    #6 is golden, not just for laptops but cell phones , iPods and other rechargable devices with smaller batteries. I’ve made the mistake of purchasing used laptops in the past from owners to clearly overcharged their batteries.

    For writers who spend the bulk of their time just writing, and don’t need constant internet access, I’d recommend getting an Alphasmart Neo word processor. It’s powered by three AA batteries for 700 hours of rated battery life (most owner go for a year without changing the batteries). It’s basically a text file buffer that connects to your PC — you can even use it as a replacement for your desktop’s keyboard. Sometimes I spend less than half an hour at the PC the whole day. I just need to review my formatted posts in WordPress to make sure my tags were accurate.

  13. Travis says:

    Idea #2 won’t work on XP unless you add a “-s” switch to the shutdown command. Executing shutdown.exe without arguments will not shut down the computer.

  14. stngy1 says:

    Great post. We’ve implemented many of your ideas over the last year and I’m sure saved significant $. Additionally, we’ve reversed our usage of desktops and laptops: I use a small laptop for everyday work, backup online and to a thumbdrive, and only once a week or so boot up the desktop. For what we do, this makes a lot more sense. I’m ’bout ready to GIVE our desktop the boot :-)
    I had been shutting down our modem at night , but it became problematic and wasn’t connecting properly. Our service provider said to leave it on. Annoying to see those blinking lights all night, though!

  15. Frugal Dad says:

    I remember there used to be an urban legend of sorts floating around that indicated shutting down your computer was bad; you should leave it on all the time, or shut it down once at night. I have heard that myth debunked from folks much more technical than I am, but I’m curious if you have any thoughts on the subject?

  16. Trent Hamm Trent says:

    “I have heard that myth debunked from folks much more technical than I am, but I’m curious if you have any thoughts on the subject?”

    That was true for very old computers because they used to draw a very large charge during startup. Modern computers (since, say, the early eighties) draw about the same power during startup as during normal use. In other words, it’s a once-true statement that’s now false but still sticks around.

  17. Grant says:

    Don’t forget to recycle or donate your old equipment when you upgrade. Don’t just throw it in the trash!

    I have plenty of resources listed for recycling and donating equipment on a new website I just launched called Leaferral – The Green Site Directory (http://www.leaferral.com).

  18. Good points Trent!

    I recently bought a timer for my furnances thermostat and it has been fantastic.

    Perhaps I’ll by some carbon credits and make my blog “carbon neutral”!

    It would be a good marketing point!


  19. Megan says:

    Excellent reading choice! I discovered Murakami last year and quickly tore through all of his work, and Wind-Up Bird Chronicles was one of my favorites.

  20. Roger says:

    A good website to go to for energy efficiency tips is http://builditsolar.com/ They have a lot of good and really cheap ways to save money, and energy.

  21. Jim says:

    Nice post.

    I’m using #1 myself, recently got one after reading about it at Terapass. I figured I’m saving about $18, but how much you save will depend a lot on your peripherals.

    For your power management settings I’ve been using a little utility from Localcooling.com at work. It lets you setup your power settings and estimates your Kwh savings. Its just an estimate but better than nothing if you don’t have a kill-a-watt meter


  22. ericabiz says:

    Hi Trent,

    You are mostly accurate, but there is one point where you are way off. A laptop charger running a fully charged laptop does NOT draw 50w. That 50w figure is for a laptop that’s running. (Run your Kill-A-Watt on it yourself and see.) A fully charged laptop should only draw a few watts in “charging” mode…likely costing you less per year than you paid for that timer.


  23. Charlie Park says:

    For anyone into this sort of thing, I highly recommend Gina Trapani’s book, Lifehacker: 88 Tech Tips to Turbocharge Your Day. It’s filled with hacks and tricks like the ones Trent mentioned.

    She has a new book out, too, but I haven’t seen it.

  24. Maine Vacation Tips says:

    Good point Grant! I have a couple of old computer monitors that i’ve been trying to unload back home. No takers yet but I haven’t tried to hard. Perhaps I’ll try craigslist.

    good article, i never realized how much it cost to run a computer.

  25. Emily says:

    My question is, does anyone know how to program exceptions for scheduled tasks. I would love to have my Media Center shutdown at 2am (it has a wonderful feature built into the motherboard that turns it on again at 9am) except when it is recording something. Periodically, we record movies or late run shows early in the morning so as not to disturb our regular schedule. But using shutdown.exe, it goes off regardless of whether or not Media Center is recording.

  26. tracy ho says:

    Those are brilliant ideals ,

    Thanks for sharing with us ,

    Tracy Ho

  27. You know these are some really great tips. It really reminds us of the concept that its the small things that matter.

    In fact that is something that i have noticed over this blog. You are always talking about the small things that you can change in your life today that will dramatically change your life in the future.

    But i think that its so important! I mean that is really what success is about.

    So thanks for sharing.

    Young Investor


  28. gr8whyte says:

    An IT person told me it’s better not to turn PCs off at night because the daily spin down and spin up is harder on the HD than if they were left spinning all the time. Any truth to this?

  29. Greener Pastures: Responsible Personal Finance says:

    Great ideas! Another little one: I leave my computer on all the time (it powers down), but always shut off my monitor whenever I’m not using it.


  30. bakednudel says:

    This is all confusing to me too. I have a 4-year-old eMac and our Mac User Group has always said to leave it on all the time. It goes into sleep mode of course. I also have (my first ever) an external hd plugged into the computer which I guess is drawing power.

    The first Mac I had at home (about 12 years ago) — I unplugged it a lot (thunderstorms, leaving for trips, etc.) and the computer’s little internal battery died. Again the guy who fixed it said not to turn it off.

    I like the idea of having a separate strip for the peripherals–but can you really include the cable modem on that? my computer is in my bedroom, and as someone else said it would be great to lose the blinking lights all night.

  31. Ryan says:

    I would say that increased hard drive usage from starting the computer up every day is minimal at best. Recent hard drives are built to last so I don’t think you have anything to worry about.


    That battery will die eventually on every computer. All it does is keep the clock going and remember some BIOS settings. You can include the cable modem on that…but if you have another computer networked, then it won’t have internet access when it’s turned off (obviously)

  32. 1WineDude says:

    Great suggestions.

    Not sure I’d call it big money though – unless of course many, many people implement them (might as well dream big after all! :-).

  33. Mary says:

    Joel, the kilowatt hour is the individual unit that your electric company bills you for (I assume most of these co’s bill this way). It could be akin to a cell phone where they give you X kilowat hrs per month for a flat rate; mine is 100 KWHs for $7~$8/month.

    So if you get 100 minutes on your cell phone and you go over by X minutes, they bill you for each additional minute. Mine bills about 15 cents per KWH.

    You could call your electric co. and ask if they have a publication, such as an “energy guide”. Mine sent it to me for free. It’s really handy for calculating the estimated use of an appliance. It also gives you a list of things stove, lightbulbs, etc. and the estimated cost for the normal use.

    Here’s the equation:

    1. Write down the wattage of the appliance in question.

    2. Divide that number by 1000 (1,000 watts = 1 KWH)

    3. Multiply the kilowatts by the number of hours you use the appliance. This could be for the day or month.

    4. Multiply the total number of KWH used by the price per KWH.

    So if a 100 watt light bulb is left on 120 hours a month, that would be 12 KWH per month and cost about $1.75

    Hope that helps clarify what Trent’s talking about!

  34. Otis says:

    For those of you using iMacs (or looking for an excuse to upgrade to one). There is no significant reason to turn off an iMac. The power consumption in the sleep state is a measly 2.7W.

    If you’re using a Mac, there’s really not much reason to ever turn them off. Unless you want to save the 2.7W. Unless of course those 0.0065 cents/day really bug you, then by all means turn it off.

  35. michael says:

    ‘Put your laptop charger on a timer’ — fantastic suggestion! Can you recommend a timer, tho? I got one from Home Depot way back (a cheap one, for lamps when I’m out of town) and it sucks — hard to set and not reliable.

    Does anyone make a decent digital, easy-to-set charger that you could recommend?

  36. How interesting to think about the CO2 emissions that computers put out. I am always looking for small ways to benefit the environment … this was full of wonderful ideas! Thanks you!

  37. I always find CO2 numbers interesting. It blows my mind to think that I am polluting just by leaving my computer on when I’m not around.

    Thanks for all the wonderful energy saving ideas. I think I’ll be getting one of those smart strips for my home computer set up.

  38. Jamie says:

    Where can I get a smartstrip? Ever since your first mention of them, my husband and I have been looking for one and we haven’t been able to find one. Thanks!

  39. Jillian says:

    “That was true for very old computers because they used to draw a very large charge during startup. Modern computers (since, say, the early eighties) draw about the same power during startup as during normal use.”

    An almost but not entirely unrelated question for you:
    Do you turn your car off at the traffic lights or in traffic jams if you know it’s going to be several minutes before you’re moving again?

  40. Kati says:

    Trent you should try out the program CO2 Saver. Its a very simple program to DL and install.
    “CO2 Saver is a lightweight program that manages your computer’s power usage when it’s idle, saving energy and decreasing the demand on your power utility.”
    You control the settings for how long your computer is idle before CO2 Saver kicks in.


  41. garry says:

    With the recent hikes in Electricity prices in the UK, I’m going to fight back by implementing some of these ideas, which I don’t already use. good, sound advice.

  42. Mary says:

    The car quesion raises a good point. I have found that I use less gas when I leave it running to run into the store, post office, etc. It seems like the act of starting it up wastes gas. I have also noticed this on road trips. If I stop at a rest area to stretch/walk around and leave the car running I have to fill up less than I would if I had turned it off even once. And I’d like to get a clear answer once and for all on the computer issue. I have heard from a reliable source (computer nerd) that shutting down/starting up the computer sends an electric shock to the hard drive and can fry it over time. I have been told that it is really more economical to leave it running or put it on hybernate mode, even with the new/er computers. Interestingly enough, I have noticed that when I am out on the road, I get less time on my batery when I select hybernate instead of shutting it down several times. I guess you have to weigh the constant use of power against the extra boost of power that occurs at startup but I really like Jillian’s comparison to turning off the car when sitting in traffic.

  43. k12linux says:

    For a home server, consider something like a LinkSYS NSLU2. They can be had for around $50. Add one or two USB drives and you have a file server that runs on 2-10 watts. It has two USB ports and a network port.

    If it doesn’t have the features you want and you are reasonably computer savvy you can install Linux on it.

    The disks can be set to spin down when not in use making this a really low-power option for a home server on the network.

  44. Mike says:

    There are many ways people can live off the grid by using solar energy. Finally as energy costs are going up the government is handing out more subsidies for solar energy. You can find a lot of info on solar energy and living off grid http://www.hardysolar.com

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