What is the cost of running a desktop machine at home?

Question

How much does it (roughly) cost to leave my personal home computer running 24/7 for a year? I'm not doing anything unusual; I run a webserver for myself, surf the web, write some code. I don't have any specific specs.

So for example there might be the cost of electricity, internet connection, and possibly some other factors that I've overlooked. I'm trying to decide whether it would be a good idea to turn off my computer when I'm asleep and not using it.

Is the cost negligible, maybe 1 USD per day, something in between or more?

Answer 1

Less than US$250, most likely

Say:

  200    Watts power
*  24    hours/day
* 365    days/year
*   0.12 US$/kW-hour
------
= 210.24 US$/kW-year

If the disk can spin down and the monitor go into power-save or be turned off completely you can get this amount down by quite a bit.

So, determine by measurement or estimate exactly how much power your system draws compared to my 200W ballpark and scale linearly. Also adjust by the difference between your power rate and my ballpark of 12 cents / kW-hour.

(Aside: I love kiloWatt-hours. Watts are energy use / time, in particular, Joules/second. And then we make a unit called kW-hours. Huh? In order to make a unit of energy we put time in both the numerator and denominator?! In order to cancel it out?! The people who hate the English system and love metric think nothing of using the most ridiculous unit of all...)

Answer 2

That would depend on your hardware configuration and the cost of electricity in your area.

What you can do is get one of these to measure the actual power consumption of your computer setup. Then look at your electricity bill which should break down the cost per kW. Armed with this info you should be able to get a fairly accurate estimate for your setup.

Answer 3

Running a web server at home might cost you your Internet connection! Check with your ISP first, especially if you expect a lot of traffic. The cost is also depending on your usage. If the processor is working hard 24/7, it needs more power than when it's idle most of the time. If it doesn't need to spin the hard disk most of the time, energy is conserved even further. Keep your monitor off instead of on standby and you save more. Try to avoid connecting all kinds of devices to the USB ports, since USB devices want electricity too, even when you don't use them.

If all you want is to keep your files accessible over the Internet, consider purchasing a network-aware external hard disk. One that you can connect directly to your network. Some smarter ones can even function as simple web servers, running LAMP.

Also, do be aware that home PC's have been created to run just a few hours per day. If you're going to use it 24/7, the system will get a lot of strain, making it more likely that it breaks before the warranty ends. Home computers tend to be made with less durable materials, which reduces the price. (Especially hard disks.) Such heavy usage might not be covered by the warranty.