Save Electricty With Your Computer




An average person who uses a computer would usually just walk away from it when your done, or if your gone for an extended time (and they know about it in advance) they'll probably put it in sleep . I (myself) use to keep my computer on about 8 hours a day, just saying I'll comeback to it later. Well there are many ways to save electricity.

Step 1: CRT Versus LCD

Many people and businesses use CRT monitors because they might have it from an old computer and say "Hey, why buy a new monitor works just fine, I'll save money."

Facts about an average 17" monitors (using the average kwh price of 9.86 cents, you can look at the map):

1) Electricity used: 80 watts
2) Money spent keeping the monitor on for 8 hours cost about 6.4 cents per day, which adds up to 23.36 dollars a year.
3) Cheapest new I could find off of Newegg was 125 dollars.
4) They're fat and ugly and take up half of your desk (well that was an opinion)

1) Electricity used: 35 watts
2) Money spent keeping the monitor on for 8 hours cost about 2.8 cents per day, which adds up to 10.08 dollars a year.
3) cheapest new I could find off of Newegg was 150 dollars

So if you have a CRT and switch to a LCD an average would save 13.28 dollars. If you had a choice of buying the CRT and a LCD you would only lose 11.72 dollars. A cheap price to help the Earth and have more room on your desk.

Step 2: Type of Computer

This part is usually ignored, because everyone has a personal preference, but this is just here so you know:

In order of electricity use from top to bottom (top uses the most)

PC Desktop
Mac Desktop

Desktops use between 60 and 250 watts of power, laptops use 15-45 watts

I'm not sure about linux systems, they're probably either the most or second most efficient.

I use a PC desktop, I like PC's cause I think they're faster and have more compatibility. Sorry Earth!

Step 3: Standby

Standy by on an average computer takes about 1-6 watts, huge improvement on a computer idling. If your going to be away from your computer, put it on standby.

(Someone please verify the following paragraph, because I'm not 100% sure)
An alternative to standby is Hibernate. Hibernate basically writes all the things on your RAM to your hardisk. Then the computer "shuts down". Whenever you "turn on" your computer it'll bott faster than when it's really off and you'll have all of your settings back, just as if it was on standby. I think Hibernate is even more efficient than Standby.

To put your computer in Hibernate on a PC
1) Click Start
2) Click Control Panel
3) Click Appearance and Themes
4) Click Display
5) Click Screen saver
6) Click Power
7) Click on the Hibernate Tab and hit OK
8) Click the check box next to enable Hibernate if it isn't checked.
9) Close all of those windows
10) Go to the shutdown menu
11) Hold shift and Hibernate will replace Standby.

Step 4: Screensaver

Screensavers act as if the Screen is still fully on, don't use screensavers!!!

Step 5: Pust a Button

See that button with a circle and a line on your monitor? If you push that button when your computers off you save at least 5 watts of power!

Step 6: See How Much Power We're Saving

This summerization will not include changing your computer

Switching to a LCD monitor: 45 watts
Puting your computer on standby/hibernate: 59 - 244 watts
Turning off your monitor: 5 watts
Screensaver: No savings

If you have a CRT you should switch to a LCD, lot of power there.

Over all if you do all of these changes you could save up to almost 300 watts! If you have 2 or 3 computer in your house it could add up to 900 watts, if you run a business that has 100 computers that leaves your computer on overnight you could save 3000 watts! By taking a couple of second of your life and putting your computer on standby or off you could save up to 300 watts.

Step 7: Why Do It?

If everyone doesn't be lazy and spend litterally seconds putting there computer on standby, or gets an lcd screen you will be saving a lot of electricity! Come on! Do it for the Earth!!!



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    74 Discussions


    3 years ago

    A good way to save electricity with your computer is to sleep or hibernate it when not in use. There are programs that do this automatically, such as WinSleep by MollieSoft - it lets you set up usage limits and a time schedule controlling when the computer should sleep. You also get an historical graph of when the computer was awake or asleep. See molliesoft dot com slash winsleep.


    7 years ago on Step 2

    This is really misleading information.

    Firstoff, a Mac Desktop is made of laptop components, so apart from a huge screen, has equal or near equal power consumption to a laptop.

    Operating system does have an impact on power consumption in the loosest sense. That sense being that increased workload from any application (OS, Office, browsers, games) will result in more power drained. We know this is true because when playing a high-end game, the graphics card heats up, and the heat energy comes from electricity. Same idea on a phone (i.e. Iphone), games will make it heat up, and also drain the battery faster.

    Therefore, because there are so many varieties of Linux, technically Linux will be the most power efficient because many Linux versions are built specifically to use low power. Also, Macs and Windows PCs are generally loaded with a greater amount of bloat ware which typical users do not remove, which causes increased power drain.

    Finally, my computer uses a 1 kW power supply. Desktops may typically use between 60-250, but there are a significant number up to 500W and many high-end up to 1kW or more. Past comments are correct, comptuer power demand is almost entirely dependent


    8 years ago on Step 6

    I hate math, but maybe you wanted to say 10 PCs, 300W*10= 3 Kw, not 100 PCs (30Kw) it's a huge company :P


    9 years ago on Step 2

    For all the people who say OS doesn't matter:
    Windows is slow after the first 6 months. It takes longer to do the same functions, therefore more power draw. Also, CPU load is increased, which uses more power.


    9 years ago on Introduction

    Almost anything with a x86 compatible processor is considered a PC, laptops are all PCs and how comes the idea that a PC could only run windows, a linux machine some other thing? linux machines are all PCs as well (of course because linux is open source it has been ported to several other platforms).
    And OS-es doesn't have to do much with power saving, except if they are able to control the CPU voltage or something, which is not really used out.


    9 years ago on Step 6

    If you are running three or four computers in one house, consider getting a KVM switch...then, no matter what the type -  CRT or LCD -  you're only using 1 monitor.

    I've personally cut back from 3 CRTs to 1 LCD. I have more space on my desk ( I HAVE desk space) and the electric meter has stopped whizzing around...


    11 years ago on Step 3

    Hibernate is pretty much as you described it. All RAM is dumped to disk. Then restarting is the time it takes for the motherboard to get ready plus the time to copy the RAM back from disk. It's much faster than a full boot up, but slower than recovering from standby. There's also a deeper sleep state that can reduce the power used at standby. I believe it's called S3 standby. Most of the parts actually turn off, but just enough power is used to keep the RAM alive and I'd imagine a few other important tasks. Support isn't necessarily great for this. I've been able to get it working on 1 of 2 computers I've tried.

    1 reply

    Reply 9 years ago on Step 3

    That's the 1-6 watt standby the author mentions.  In S3, the power supply actually goes into off mode and the motherboard stays alive using the +5Vsb supply.


    9 years ago on Introduction

    alot of people forget that software now days does change the running of hardware for example a GPU will run at higher clocks then on the desktop thus more watts are used why do you think Nvidia ATI say to make sure your PSU is this many watts ect. but also yes Running different software will use more or less power depending on how complex it is and i am very surprised at alot of people that think other wise and then sit there and argue the point with out doing any study on it after been told i RUN CRT 24inch screens A: LCD does not offer what my CRT offers especialy for when my computer is needed for REAL TIME aplications one would be SCOPES i dont care what any Co. tells you about LCD but there is a DELAY still today especialy when you are competeing with monitors like the Hitachi ACCUVUE 240Hz Refesh Rates that uses even more power TO DEV45 he has a idea what he is talking about and MR C64 on some things and for MR64 MAC is not classed as a Computer its Classed as a E.T Device for people who have little or no idea what to use a Computer for. MAC OS yes is very close to Linux and even has some core programing from it but its NOT EVEN Close to Linux in terms of Functions. as for Windows and DOS they would use more power then anything else DOS been more so because it does not have ACPI ( power Management it just runs hardware at full speeds hence some people video cards Fan Runs at full speed in boot and dos mode as for Hybernation mode for computers i hate to tell you if you really understand how that works you would not sit here and say it saves power because it does not 1 it creats a page file ON YOUR HARD DRIVE OF YOUR RAM thus meaning when your computer in in hybernation it needs the CPU in sleep mode or what ever you want to call it the ram is still ACTIVE the HARD DRIVE IS still active but the Spindle is PARKED meaning all these devices are just waiting for you to move the mouse oh yes your mouse and all your usb devices are drawing a max of 500ma per port thus meaning your south bridge is active and waiting for your commands. Standby mode your computer is mostly off e.g monitor , hard drive is in spindown ( parked ) CPU is in sleep mode, some computer fans will be off ( not the PSU FAN.) ram is still running as all your programs are there so i would have to say for Computers it does not save power. what this function was made for so people who did have laptops and run out of power would not loose there work so that when the laptop has power the it will boot and load this page file into mem so all your stuff is there so that is different again to the normal H-Mode because you have Run out of BATT power thus you would use nothing but on a Computer you dont run out over power hence everything is still on yes far less then when your using it but not less the standby. so before been a child and commenting that people know nothing because of english grammer ect. i think you should take a step back and look at a Logical view. Find out how it works for your self. thank you for the instructable not what i was expecting but some of the things you said where right but not all but that is why we have such a site to gain input from other people that may or may not know more so to all the people reading this please remember why this site is here remember why we can write comments to help each other gain more NEED FOR INPUT. thank you.


    10 years ago on Step 7

    Hibernation isn't really an option in my opinion simply because when enabled it can soak up quite a bit of ram and degrade processor performance. Which could make your computer slow. This would cause you to be on longer and then in effect use up more energy. Standby is fine and when your going to be gone for long periods of time then simply shut it down.


    11 years ago on Step 2

    This is incorrect. The operating system on the computer has absolutely nothing to do with its power consumption. It all depends on what hardware you have loaded in the computer. Both Linux and windows can both be run on an extremely wide variety of hardware. Hell you can even run Windows/Linux ON a mac. For example if you have windows on some Bigass gaming rig with 4 graphics cards, double quad core processors, a 12000 rpm 1000 GB hard drive, and a liquid cooling system, it's going to use a hell of a lot more power than a little $400.00 Dell word processing machine. I mean, both would have XP on them, and both could have Linux on them just as easily, but that wouldn't make them use any less or any more power.

    8 replies

    Reply 11 years ago on Introduction

    This information is correct. All depends on what specifications you loads inside.


    Reply 10 years ago on Step 2

    ASL / ESL actually. ( American Sign Language / English Sign Language ) Should have said " It depends on what requirements the hardwares actually need." Thanks for pointing it out.


    Reply 10 years ago on Step 2

    No, the plural of 'hardware' may not be 'hardwares', but multiple types of hardware, such as ram chips and hard drives would be hardwares, just like multiple types of cactus would be cactuses. Most people don't realize this, which is why it is red when you type in cactuses (also, instructables doesn't want us to be vague and use multiple types of hardware as a description in our instructables).


    Reply 10 years ago on Introduction

    Yeah, such as: "I cut many types of CHEESES." I don't think you can say "Geeses" however. Hmm, 'Geese'? why isn't the plural of mice Meece? oh well.