Power Consumption: How Many Watts Does a Laptop Consume?

Power Consumption How Many Watts does a Laptop Consume

What Do You Think About When You Use Your Laptop?

Perhaps you’re questioning how fast your internet is, how long your battery’s lasting, or how loud your fan is. Wondering how many watts your laptop consumes may not be high on your list. Regardless, it’s an important question to ask, and we’re here to help you answer it.

Understanding your laptop’s power consumption and how to reduce it can put you on the path to a greener, cheaper, and more energy-efficient lifestyle. So what have you got to lose?

Ready to find out more? Let’s explore the ins and outs of laptop power consumption and find out if your machine is a power-hungry beast or a savvy energy saver.

What Is Watts?

If you need a refresher, let’s go back to basics.

In short, Watts is a unit of power. You’ll usually see Watts written as a W, and it’ll appear directly after a number. (e.g. 18W). Watts are a base unit of power, and they’re used to describe and measure how much energy is released per second.

How Do You Calculate Wattage?

In most cases, you won’t have to calculate wattage yourself. If you ever need to, there’s a simple formula you can follow:


That’s it! To determine wattage, you’ll simply need to times the number of amps by the number of volts, and you’ll have the answer.

The manufacturer almost always supplies the number of amps and volts of an electrical device.

What Factors Influence Energy Consumption?

The energy consumption of your laptop depends on several factors.

First, different laptops have different purposes and components, influencing how many watts your device guzzles through. Let’s take a look at the most common factors that increase energy consumption.

1) Laptop Model

The average laptop uses around 50 watts of electricity. The key term here is ‘average.’

We’re talking about a standard laptop you’d use for work or school that isn’t running any unique software or packed with expensive, top-of-the-line components.

If you’re using a model like a gaming laptop, energy consumption increases quickly. The average gaming laptop consumes between 160 to 185 watts of power – a VERY noticeable increase. So, what’s behind the leap?

Gaming laptops are far more advanced. To handle heavy games and intense graphics, gaming laptops often come with a heavy Graphical Processing Unit (GPU).

GPUs manipulate and process the creation of images on a device, and the average high-end GPU can consume between 70 to 300 Watts. This number can vary, depending on how heavy the games are and what work the laptop is performing.

2) Central Processing Unit (CPU)

You’ll find a CPU in almost all electronic devices. A CPU is the ‘brain’ of your laptop, and it’s responsible for processing instructions from a program or application and performing tasks.

Laptop CPUs tend not to be as advanced as Desktop CPUs, which can hold more Random Access Memory (RAM) and run higher-quality video cards than most laptops.

However, you’re unlikely to notice the difference unless you’re performing intensive tasks like editing and processing.

The average standard laptop CPU uses between 40 to 50 Watts of power. This increases for gaming laptops, which can use around 100kWh.

3) Laptop Fan

Compared to the laptop model and CPU, the laptop fan uses a minuscule amount of wattage. If your fan is working correctly, it should only use between 1 to 3 Watts of power.

However, the CPU can begin to overheat if your fan isn’t functioning optimally (perhaps due to a build-up of dust or debris). Not only will this require a higher wattage, but it can damage your system and cause it to shut down.

4) Solid-State Drive (SSD)

Your laptop’s Solid-State Drive (SSD) performs similar functions to a hard drive.

The only difference is that with an SSD, data is stored on ‘flash-memory chips’ that can preserve data, even when there’s no power supplied to them.

An SSD storage device is an integral part of any laptop or desktop computer. Most SSD’s use just under 5W. When they’re idle, they can consume as little as 3mW to 10mW.

5) Laptop Adapter

Your laptop adapter provides the power supply for your device. It’s the charger that plugs into your wall outlet and attaches directly to your laptop.

Regardless of what model you’re using, each adapter will consume a significant wattage.

Some laptops can take less than 20W to reach a full charge. With most laptops, 70% of the energy sits in the charger, and the other 30% is released as heat.

The United States Department of Energy estimates that a standard laptop charger uses around 50W of electricity.

For reference, the average 15.6-inch laptop comes with a 60W charger, and most 17 inch laptops come with a 90W charger.

However, this number fluctuates depending on the size of your laptop and the tasks you’re performing.

For example, a smaller model with a slow processor and a lower-power GPU can consume as little as 15-20W when idle and 90W when in use.

For gaming laptops (AKA notorious power-hungry suckers), the wattage increases. With more advanced components, the average gaming laptop requires a charger between 90 to 200W.

6) Hard Drive

Your hard drive stores all of your laptop’s permanent data. This includes all digital content, from documents and programs to music, pictures, and videos.

The hard drive performs some pretty intense tasks, and as a result, it requires a fairly significant wattage to function. So let’s take a look at how many watts the average hard drive requires.

Note: Hard drives come in two main sizes: 2.5 inches and 3.5 inches. The figures below are a rough estimate and may not be representative of all hard drives.

Idle Hard Drive: 15W

Sleeping Hard Drive: 14W

Defragmenting Hard Drive: 18W

Although we’ve covered the main power-hungry offenders, there are a few other factors that can influence your laptop’s power consumption. These include:

  • Screen brightness
  • What software you’re running
  • Whether your laptop is charging or not
  • How hard your graphics card is working

Does A Laptop Use More Power When Plugged In?

Yes. The power consumption of the average laptop will increase by 10% when charging.

However, this may be less if you’re using a smaller laptop like a notebook, which generally requires less power than a high-end laptop or a gaming model.

Power consumption will also depend on other specifications like screen size and what software you’re running.

How Much Does A Laptop Cost To Charge?

Surprisingly, keeping your laptop (and other electronic devices) charged up is cheaper than you might think. So let’s take a look at some rough estimates.

Note: Electricity prices vary; these estimates are based on 10 cents per KWH.

There are 8760 hours in a year. Keeping your laptop charged 24/7 for the whole year would cost you $32.40. Not bad, right?

The United States Department of Energy estimates that the average laptop consumes 50W a day (or 0.05kWh).

Using the 10 cents per KWH model would cost you 5 cents to charge your laptop for the day (an average of 8 hours).

Power Consumption: Apple MacBook

Are you an Apple MacBook user? Ever wondered how many watts your MacBook uses? Let’s take a look below.

MacBook Pro 13”

To get a more accurate estimate, we need to choose an exact model. For this article, we’re going to look at the energy consumption of a MacBook Pro 13”.

We’ll be assuming that the electricity cost is 12 cents per kWh.

The Macbook Pro 13” uses a 61W USB-C Power Adapter and USB-C Charge Cable, according to the Apple website. Therefore, a typical 13” MacBook pro consumes 61W of power (or 0.061kWh).

If you were using your MacBook for eight hours, this would cost you 5.86 cents a day.

Power Consumption: Gaming Laptop

Power Consumption Gaming Laptop

Ever wondered how much power a gaming laptop uses? Let’s take a closer look.

Acer Predator Helios 300

The Acer Predator Helios 300 is one of the most popular gaming laptops in the world. It boasts some impressive features like a 15.6” screen, RTX 2060 Graphics Cards, and a Hard Disk size of 512GB.

Note: all of these features WILL have an impact on power consumption.

The Acer Predator Helios 300 comes with a 180Wh charger. However, the maximum is rated at 135W (0.135kWh).

If you were using this gaming laptop for eight hours a day, it would cost you an average of 12.96 cents – a notable increase from the Macbook Pro 13”.

However, this estimate is purely based on the wattage of the charger. Gaming laptops also include other high-tech specifications, specifically in the CPU and GPU components.

For a more accurate estimate, you would need to have the maximum power consumption estimates from the manufacturer for each of these components and include them in your calculations.

The consumption for both of these components can be anywhere between 45 to 75W, so you can expect another notable increase in price here.

Calculating Power Usage: Electricity Monitor

Although calculating your laptop’s power consumption is pretty easy to do manually, you may find it easier to use an electricity monitor. An electricity monitor can calculate precisely how much power your laptop is consuming from your wall socket.

These can also be used to calculate the power usage of any electrical device in your house – they’re a worthwhile investment and an excellent way to keep on top of your electricity consumption.

Electricity Monitors like the Poniie PN2000 have a simple ‘plug-in and go’ set-up. This high-power wattmeter can calculate the consumption of any electrical device by kWh, and it allows you to start detection at 0.20W.

You can also monitor the consumption of any device, whether it’s idle or in use.

If you want something that can calculate the cost of your power usage, you can invest in a meter like Sense Energy Monitor.

This meter can provide you with an in-depth analysis of the cost of each electrical appliance in your home, including your laptop. It also identifies patterns in your usage to help you use your electricity more efficiently. This is a great little device for households who want to be more energy-efficient.

Does Laptop Wattage Differ Between Brands?

While the rules for calculating wattage remain the same, the wattage between each laptop brand can differ. For example, the total wattage may increase if the laptop has complex specifications, such as a high GPU.

However, if you’re comparing two laptops with similar specifications, their wattage is likely to remain the same, even if they’re different brands.

Do Desktop Computers Use More Power Than Laptops?

Often, yes. Laptops are smaller and have less intricate components than desktop computers. This makes laptops are more energy-efficient alternative.

Desktop computers are also attached permanently to your wall sockets, so naturally, they consume more power.

Can You Consume Less Power On Your Laptop?

Thankfully, you can use a few tips and tricks to decrease your power consumption and make your laptop more energy efficient. Let’s take a look at some of the most effective ways below.

1) Disconnect Peripherals

The term ‘peripherals’ refers to any external devices connected to your laptops, such as a mouse, an external DVD drive, or a USB device.

Keeping these external devices connected to your laptop will naturally consume more power. When not in use, it’s always best to disconnect your peripherals to optimize your energy efficiency.

2) Use A Smart Power Extension Cord

A smart power extension cord, or smart power strip, is helpful to monitor your consumption and reduce waste.

Unlike a typical extension cord, you can monitor the power source to each socket via an app or a switch. This means you don’t need to power every single device plugged into the cord, even when you aren’t using them.

Some devices even allow you to schedule timers to each individual socket, giving you more control over your consumption.

If you think you could benefit from a smart strip cord, you can check out this model from Meross.

It’s even compatible with Siri, Alexa, and Google Home, so you have more control than ever over your electricity consumption.

3) Shutdown Your Laptop

Instead of keeping your laptop running on standby, shut your laptop down completely when it’s not in use to save energy. When you do shut down your laptop, unplug it from the wall outlet unless it needs charging.

Even if your laptop is shut down, it will still consume power when it’s plugged into the socket.

4) Make Use Of Energy-Saving Settings

Whatever the brand, each laptop comes with its own energy-saving settings. Most of these can be accessed by clicking directly on the battery symbol in your taskbar or heading straight into settings. Energy-saving options can include:

  • Low battery mode
  • Airplane mode
  • Dark mode

Final Thoughts

If you’re using a standard laptop, estimates suggest it will consume an average of 50w of electricity.

However, this can increase if you’re using a laptop with more advanced specifications – as we’ve established, gaming laptops are one of the worst offenders!

Whatever laptop you’re using, the formula for calculating your wattage remains the same.

If you don’t want to do this manually, you could invest in an electricity monitor to do the job for you.

Although the power consumption for each laptop is different, it’s probably NOT as expensive as you originally thought.

Thankfully, there are several things you can do to optimize your laptops efficiency, including changing your brightness, using energy-saving settings, disconnecting peripheral devices, and more.

For a more accurate measurement, we always recommend using a device to measure your power consumption so that you can get the most reliable results.

Brett Jones
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