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Computer monitors allow you to expand your workstation, game station, or viewing space by connecting to laptops, PCs, or game consoles. You can use a single monitor or connect multiple for a larger area with access to multiple programs, documents, and files. One downside of computer monitors is they use quite a lot of energy. So much so that there are regulations in place to label how efficient monitors are at using and saving energy.

Monitors constantly emit light while being used, making them use a lot of energy while you work, game, or stream content. According to Digital Europe, monitors have become around 41% more energy efficient since 2011. Further studies reveal that they can become more energy efficient at around 7.5% per year, but that calculation may not be sustainable in the long term. You can find more efficient monitors and potentially save some cash by looking at energy class and Energy Star certified displays. The higher the letter rating, for example A, means the monitor is highly efficient at conserving energy.

Monitors aren't the only home devices that use more energy than you think. Larger appliances such as refrigerators use a lot. The same is true for larger monitors with bigger screens. Brighter screens have the same effect. If you want to save on your monthly bill, get a monitor with a higher energy class rating and one that's Energy Star certified.

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There are two ratings, numbers, or letters you need to look out for when buying a new computer monitor. The first is energy rating, but it's only viable in Europe. The second thing is Energy Star certification. Energy Star is a U.S. government-approved standard for energy efficiency on devices. It's noted by a blue Energy star symbol stating an item is more energy efficient.

Energy Star doesn't feature a number or lettering grade system to let you know how efficient a device is. Rather, it's a system that informs users that what they're buying or using is more energy efficient than other devices. According to Energy Star, Energy Star certified monitors are 7% more energy efficient when compared to standard monitors. The Energy Star symbol indicates monitors conserve more energy when turned on, in sleep mode, and turned off modes. It works best when bundled with other Energy Star certified devices in the same house or building.

One performance indicator found that on smaller monitors, on-mode power levels are based on the screen area and resolution, while larger monitors are based on the screen size alone. Larger monitors with higher resolutions — 4K monitors are great, but can use more energy — tend to have higher maximum on-mode power level allowances than low-resolution and smaller monitors.

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Not all computer monitors are marked as Energy Star certified. You can find official ones listed on the Energy Star website, such as the ViewSonic VX1655-4K VS19590. Computer monitors must also meet certain requirements in order to become Energy Star certified. They must have a total energy consumption that doesn't exceed certain limits, with different numbers applying to on-mode, sleep mode, and being turned off. Screen size and resolution plays a role in these limits.

In the last 15 years, monitors have improved energy efficiency, therefore making it possible they could be even more efficient in the future. Improvements such as updates to LED backlighting conserve more energy than alternative options. With the ability to control the brightness of the backlight, it's just another way one could lower their monthly bill.

There are ways computer monitors — even cheap computer monitors — can become more energy efficient. If they act more like a laptop monitor with the ability to automatically adjust lighting, sleep mode, and power cycles, instead of manual adjustments, one could set routines to dim and turn off the screen at certain times. To further improve in the future, monitors will have to produce fewer watts overall in order to become more energy efficient. In the meantime, you'll just have to manually adjust your monitor screen or unplug it after the workday ends to optimize your cost savings.