How Many Watts Does a Computer Use?

Computers are a necessity of the modern age but they can add extra price to your utility bills. If you just received your utility bill and it's higher than usual, it's reasonable to check your PC's power consumption. This depends on how much work or how many amps a computer uses.

Learning how much energy a computer uses and the factors affecting a PC's power consumption will help you implement strategies to reduce that consumption. In this article, I answer questions like "How many watts does a laptop use" and explain how you can reduce your computer's power consumption, ultimately lowering your electricity bill.

How much electricity does a computer use?

Even though computers use less electric power than many larger household appliances, they may still be a power hog in your case.

So, how much electricity does a PC use? Usually, a desktop computer uses 70-200 watts while a laptop consumes around 30-70 watts. However, some gaming PCs can intake more power. And, how many watts does a gaming PC use you ask? It can range anywhere from 200 to 500 and even more, if you're using power-intensive hardware.

The amount of time you use your computer per day plays a huge part in determining its power consumption. Let's say your PC consumes 80 Watts per hour and you run it for 8 hours daily.

• Your total power consumption would be 640 watt-hours per day.
• If you multiply your per day consumption, 640 watt-hours in this case, by 7, you have your weekly electricity utilization. Here, it will be 4.48 kWh.
• At the same pace, your monthly power use will roughly be around 17.92 kWh, and yearly would be 215.04 kWh.
• For a heavier PC using 300 watts per hour and running for 8 hours a day, the estimated daily power utilization will be 2.4 kWh. Per month, it will consume 72 kWh and a hefty 864 kWh annually.

If your numbers are different from mine, just multiply your computer's wattage by the hours you normally operate it. This will give you an estimate of how much electricity your computer uses per day.

Wattages differ for various computer types. Here's how much electricity an all-in-one computer uses in comparison to laptops and PCs.

Computer type	Watts used
Laptops	30-70
All-in-one computers	Around 65 watts
Desktop computers	70 to 200 watts

How much does it cost to power a computer?

There is no one-size-fits-all. The cost usually depends on multiple factors like the electricity rates in your state, your PC's wattage, and how much you use it. With electricity and fuel prices rapidly increasing, you'll be surprised by how much it costs to power a PC today.

Here's a breakdown of how much running an average 70-watt computer for 8 hours per day will cost in different states in the US.

State	Electricity rates per kWh	Monthly cost
California	30.44 cents	$5.11
New York	25.21 cents	$4.23
Ohio	15.86 cents	$2.66
Texas	14.83 cents	$2.49
Florida	13.6 cents	$2.29
Hawaii	44.14 cents	$7.41

To calculate the price of your computer's monthly usage, put your values in this simple formula and there you have it.

Cost = monthly power consumption (kWh) x electricity rates (per kWh).

So, if I live in Arizona my electricity rates would be $0.1485/kWh. When my 200-wattage desktop consumes 36 kWh per month, my monthly running cost for the computer will be $5.346 (36 x 0.1485).

Do computers use a lot of electricity?

Average home PCs do not use a lot of electricity. However, heavier systems or gaming computers utilize a significant amount. But, if you were to compare a computer's power consumption to other larger appliances like HVAC or washing machines, computers are more energy efficient.

So, why are computers more energy efficient you ask? There are multiple reasons for that. Let's discuss them.

1. A computer has fewer mechanical parts than appliances like air conditioning units and refrigerators. And mechanical components require more electricity than electronic components.
2. Secondly, as technology evolved, computers started having more and more energy-saving features. Modern-day computers have features like sleep mode that makes your hard drive and monitor go to sleep after a few minutes of inactivity. So what required less power before, now consumes even less electricity due to added energy-saving features.

Factors that affect computer electricity usage

From hardware architecture to computer software, there are multiple factors affecting your computer's power consumption.

1. Software

When a computer is performing a resource-intensive task that requires complex computation and heavy hardware components like GPUs, it can increase power consumption.

Operating systems also play a vital role in energy utilization. A computer running a well-designed OS with better resource management features will be more energy efficient as compared to the ones using suboptimal system software with poorly written asset management features.

2. Hardware

The kind of hardware your PC uses also determines its electricity usage. For example, an SSD storage with no moving parts uses less power compared to an HDD.

Additionally, components can be broken down into form factors. So, a motherboard has multiple form factors (physical specifications like dimension and power supply). Different form factors have different energy-saving capabilities. For instance, a Nano-ITX consumes way less power than an XL-ATX motherboard used in extreme gaming setups. A Nano-ITX uses around 15 to 30 watts while an XL-ATX consumes 300 to 600 watts.

3. Frequency of usage

This one is quite obvious. The longer you run your system, the more current it will draw, hence power consumption.

Shopping for an energy-efficient computer

Now that you know what factors affect your system's energy utilization, you must be somewhat aware of what to look for when buying a PC. Here are the two important things to consider when shopping for an energy-efficient computer.

1. Look for ENERGY STAR certification

An ENERGY STAR certification in computers means that a computer product utilizes efficient power management features and electricity-efficient power supplies.

When looking for ENERGY STAR-certified products you may also come across the term "ENERGY STAR rating" which tells you how much energy a product uses. So, a computer rated less stars consumes more energy and the one with more stars uses less energy. This rating will make finding power-efficient PCs easier.

One major benefit of using an ENERGY STAR-certified computer is that your electricity bills will be reduced. Further, it will help reduce carbon footprint by consuming electricity efficiently favoring the environment.

2. Consider a laptop instead of a PC

If you can buy a laptop instead of a PC, you should, as it utilizes less power than a standard desktop system. Laptops are battery-operated, while a PC needs to be plugged into a power outlet for as long as you need to run it.

Alongside energy efficiency, laptops provide the added benefit of portability. You can effortlessly carry them with you making it easier to work from anywhere you want.

Tips for reducing electricity consumption when using a computer

Did you know that just making a few adjustments in your PC settings and how you use it can make it consume less power? I've compiled a list of practical tips you can implement to prevent your PC usage from hurting your pocket so much.

1. Disconnect your peripherals

External devices like printers, headphones, and scanners consume electricity too. So when you're not using them keep them unplugged.

2. Adjust power settings

You can change your computer's energy settings to ensure less power consumption. For instance, set your monitor and drive to go into sleep mode whenever they're left idle for some time.

3. Unplug your computer when not in use

When you shut down your computer, leaving it plugged in causes it to draw standby power or ghost load.

4. Unplug your laptop's charger when not in use

Usually, when done charging the laptop, it slips our mind to unplug the charger. Even though it's not connected to the laptop it's still consuming power.

5. Use a smart strip

If you often forget to unplug your PC, use a smart strip. It will automatically shut down your device when it goes into standby mode.

Conclusion

Many users ask, "How much electricity does a computer use?" and it's important to understand that it varies from PC to PC and different usage habits. If you use a heavy computer for long hours, it uses more electricity.

That said, you can still implement some useful tips to reduce your computer's energy consumption. For instance, adjusting power settings like lowering the brightness and turning on sleep mode.

Taking measures to use computers efficiently is a win-win situation. It reduces a few extra dollars from your utility bills and benefits the environment by minimizing your carbon footprint.

FAQs

How much electricity does a computer use in 24 hours?

There's no one-word answer! The computer's energy consumption really depends on your computer's wattage and how long you use it. For instance, a lightweight PC will consume less power as compared to a resource-intensive gaming computer.

To check how much power your computer uses in 24 hours, start by checking how many watts it consumes per hour. Then multiply that by the running time, 24 hours in this case.

Does leaving your PC on raise your electric bill?

Yes! Leaving your PC on for long hours whether it is in use or not, will raise your electricity bill. Not only is it bad for your bill, but it's also not good for the cooling fans. When the power supply is left on, it heats up. And to cool that, cooling fans will run. Generally, unlike electronic parts, mechanical components are more likely to fail when left on for longer times.

Is it better to leave my computer on or turn it off when not in use?

It's better to turn your computer off when not in use for many reasons. First, leaving your PC on for no reason will add extra dollars to your electricity bill. Also, it's bad for the environment as more energy consumption leads to an increased carbon footprint. Lastly, it's bad for your PC's components, as overheating can damage the system, reducing your PC's lifespan.