How Many Watts does a Computer Monitor Use

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Computer monitors are an essential part of nearly any computer setup, but how much electricity do they use? The answer to this question depends on the monitor’s features and the amount of time it’s used each day. But if you want to know about how many watts does a computer monitor use, then this article will be very useful for you.

1. Standard computers use about 100-250 watts

Most computers have an average power usage of about 100-250 watts. However, it’s important to note that LCD monitors can use anywhere from 35-80 watts of electricity. This doesn’t mean that you should toss your old CRT monitors in favor of LCD ones just yet; instead, it means that manufacturers have made significant advancements in energy efficiency over recent years. Your computer may be burning through more electricity than it needs to, as well.

1.1 Monitors use about 20% of the total power used by your computer

Monitors are by far the biggest power hog in your PC setup, consuming between 20% and 35% of the total amount of electricity used by your computer. To save energy, keep your monitor unplugged when it’s not in use. If you need to leave it on all the time—for example, if you have an older CRT model—look for a power-saving model that uses about 60 watts or less.

1.2 Power supply units use about 10% of the total power used by your computer

Power supply units (PSUs) are the source of all power within your computer. On average, they use around 10% of the total power used by your computer, making them the single largest consumer of power in your computer. You can, however, reduce the amount of power they use by replacing them with Energy Star–compliant models that monitor and adjust their consumption based on how much electricity is being used by other parts of your system. This reduces electricity costs while also reducing emissions and lowering overall energy consumption.

1.3 Processors use about 10% of the total power used by your computer

Your computer’s processor – the brain of your computer – uses about 10% of the total power used by your computer. Processors use low amounts of energy, typically under 35 watts and sometimes as little as 5 watts. You can think of the power consumed by processors in terms of the fuel tank in your car: it’s big enough to drive a long distance, but you don’t need an SUV to drive around town.

1.4 External hard drives use about 8% of the total power used by your computer

Much of the power your computer uses is for the monitor; about 8% of the total power used by your computer is for an external hard drive. If you’re looking to cut down on energy consumption, it might be worth unplugging any drives that aren’t in use. You can also switch to solid-state drives (SSDs), which use less energy than hard drives, although they are more expensive per gigabyte than traditional drives.

2. Modern versions of windows can help you reduce energy usage

Windows comes with built-in energy-saving features that you can use to help reduce your monitor’s energy usage. For example, when you are not using your monitor, Windows 8 and 10 will automatically go into sleep mode. To reduce your energy usage even further, you can also change several settings. Under Adjust screen brightness automatically, you can adjust how much time Windows waits before it dims or turns off an inactive screen.

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3. The detailed computer monitors with their voltage consumption

3.1 CRT Monitor

The voltage consumption of CRT monitors varies from 25 watts up to 80 watts. Older or cheaper models tend to have higher consumption, while more modern and expensive CRT monitors have lower consumption. The impact on power costs is low for an old monitor and medium for a recent one, with both between $6-$20 per year depending on your electricity costs. More expensive monitors are more sustainable over their lifetime thanks to their relatively low energy consumption during use.

3.2 LCD Monitor

Most LCD monitors consume between 60 watts and 120 watts. This makes them considerably more energy-efficient than their CRT predecessors, which used 100 to 180 watts of power. For example, LG Electronics’ 20-inch Class LED Monitor uses 36 watts, which is about 12 percent of what a CRT monitor would use for similar performance. If you have an older LCD screen that uses up more power than newer models with comparable features, it may be time to buy a new monitor.

3.3 LED Monitor

The best LED monitors are highly energy-efficient and use up to 85% less power than their LCD counterparts. LED monitors also come with minimal environmental impact, as they contain no mercury like their fluorescent counterparts. With an average voltage consumption of 23 watts and a range of 35 to 80 watts, LED monitors won’t drain your electricity bill.

3.4 Plasma Display panel

A plasma display panel (PDP) is similar to an LCD panel in many ways. They both use an electrical current to change light-emitting diodes (LEDs) on and off, but PDPs also generate their own voltage with internal high-voltage circuits. This high voltage allows them to create deeper blacks than LCDs—and sometimes even grays. However, Plasma Display panels require about 35 watts of power in order to operate, which is significantly more than LCD monitors do.

3.5 Touch screen Monitor

You should consider also that with monitors there is another thing that can increase electricity consumption and it’s Touch screen monitors. Before buying a touch screen monitor make sure that you know exactly how much electricity it needs. For example, LG IPS234V 23-Inch Full HD Touchscreen LED-Backlit LCD Monitor uses 45Watt. So do not forget to check if your monitor uses power or not! You can easily get stuck paying more than necessary if you do not notice such an issue.

3.6 Energy Star Monitors

Energy Star-certified monitors consume up to 75% less energy than standard models. That’s only 8 watts per hour—less than an average light bulb.

4. Frequently Asked Questions FAQs


4.1 How much power does a 24 inch monitor use?

If your monitor uses a 60Hz refresh rate, it will draw between 20W and 35W at all times. However, if you crank up your refresh rate to 120Hz, it will use between 35W and 80W. Also note that LCD monitors tend to use more power than plasma displays when displaying static images, but consume less power when running in motion. Given all of these factors, there’s no easy answer for how much power a 24 inch monitor uses because every unit is different.

4.2 How many watts does a 27 inch monitor use?

If you have a 27-inch monitor (or an even larger screen) that’s always turned on, it’s easy to wonder how much power it uses. Like many devices in your office or living room, computer monitors use electricity when they’re turned on, even if they’re not actively being used. Just like a cell phone and other electronic devices, computers use more power than older models.

4.3 How Many Watts does a Computer Monitor Use and Do PC monitors use a lot of electricity?

Modern computer monitors use between 20 and 30 watts of power, according to some estimates. So let’s do a little comparison. If you leave your monitor on 24 hours a day for 30 days, it would consume 6,480 kilowatt-hours (kWh) of electricity, or 648 kWh per year.


Monitors typically draw more wattage than desktop computers and can use up to 80 watts when in use. However, it’s also important to consider that monitors are turned on for hours on end, which can lead to very large power bills. Your best bet is to be aware of your computer’s total energy consumption as well as monitor energy consumption specifically. Both factors should be taken into account when looking at energy-saving strategies.