Why Your Laptop “Sucks”

by Betty on January 11, 2013

Hey there all you green kids! I hope everyone had a wonderful holiday season and that your 2013 is off to a great start! Are you looking for ways to be greener this year? Well, I’ve got some tips for you about your laptop.

That’s right – your laptop. It turns out your laptop could be using much more energy than you think. In fact, it’s what is called an “energy vampire” because it sucks up energy even when you’re not using it. Apparently “vampire” power accounts for 10% of residential energy use in the United States and 1% of CO2 emissions worldwide. I know it may be annoying to worry about this stuff. If you’re anything like me, you have your laptop plugged in and in sleep mode whenever you’re not using it so that it’s always ready to go. But, it turns out that’s not too Earth friendly (or wallet friendly – obviously, the more electricity you use, the higher your monthly power bill).


Here are a few stats I found about laptop power usage that are pretty interesting:


  • While your laptop is charging, it consumes (on average) 44.28 watts of electricity (remember watts are a measure of rate of energy transfer in terms of joules per second).
  • A fully charged laptop that is still plugged in, on average, 29.48 watts of electricity. That’s 66% of the energy it uses while charging, so a fully charged laptop still consumes pretty heavily.
  • In sleep mode, your laptop (while plugged in) will still consume an average of 15.77 watts of electricity.
  • When turned off, your laptop (while plugged in) will draw on about 8.9 watts of electricity – that is still 20% of what an actively charging laptop uses!
  • Your power cord even uses electricity when your computer is not connected to it – 4.42 watts on average, or 10% of what an actively charging computer uses.


There’s no question – laptops can definitely use up a lot of energy. Let’s say you plug in your laptop for 10 hours a day. If we assume that your laptop is in sleep mode and fully charged that whole time and that you unplug your charger when it’s not in use (obviously very conservative), then you are using .1577 kilowatt hours (kWh) of electricity per day ((15.77 watts x 10) / 1,000). That’s 57.5605 kWh per year. According to EPA converters, that will result in .04 tons of CO2 emissions, or 80.5847 pounds. Doesn’t seem too outrageous, right? But, that’s just for one laptop. If every UVA student did the same thing (all 20,895 of them), it would result in 841.9 TONS of CO2 emissions each year. That’s using our conservative figures.  That’s a lot! Especially considering that’s only for laptops, not TVs or cellphones (or iPads or gaming consoles or hair dryers or coffeemakers – the list goes on and on).


Yes, that’s a lot of energy used by your laptop. But it’s not like you’re going to stop using your laptop! Let’s be real, we have all become pretty dependent on our computers for productivity, not to mention communication and entertainment. So what are you supposed to do if you want to be a little greener?


  1. Use your laptop instead of a desktop. You’re already made a greener choice by choosing to use a laptop (woohoo!). Because they were designed to be more energy efficient to enable portability, laptops use up to 80% less energy than desktops!
  2. Keep your laptop plugged in while using it. If you’re using your laptop for an extended period of time, try to keep it plugged in. An NRDC study estimates that laptops operate 20% more efficiently when running off of AC power instead of battery power (so running off of battery power will require more charging time). BUT, some laptops are set to be more efficient when running off of battery power, so be sure to check your energy settings.
  3. Unplug your chargers when you’re not using them. But this is can be pretty inconvenient if you have to do that for all of your appliances, so…
  4. Use a power strip or smart power strip. If you plug electronic devices into a power strip, you can very easily just turn off the power strip before you leave the house. Smart power strips are even more convenient – they stop drawing power when devices are not in use (meaning your laptop is turned off). Take Charge sells a highly rate smart power strip on Amazon.
  5. Try an energy conserving outlet. Don’t want to turn your devices off? You can buy sockets that will cut off after a set period of time. So, you can plug your laptop in at night, set the timer for 3 hours while it charges, and then the socket will stop drawing power after those three hours. Check out the Conserve Socket from Belkin on Amazon.
  6. Buy an Energy Star laptop. When it’s time to buy a new laptop, make sure you buy an Energy Star-rated laptop and turn on the energy saving settings.


I’d be willing to guess that most students’ laptops consume more electricity when they’re not in use than when they are. But that doesn’t have to be the case. Try out a couple of these tips and you could eliminate a significant chunk of that “vampire” power you’ve been using. And while one single laptop may not make a difference, if we all make these small changes, we could make a real difference.


Got any more tips for reducing vampire power used by your electronics? Share them in the comments!

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