How much power/money is used by keeping a F@H running 24/7 on a computer?

[Humboldt]

Not sure how accurate this is, but since it comes right from Stanford it should be at least based in reality somewhat...The main fault I see is that they seem to be addressing original Pentiums maybe, while the consumption of modern systems is much higher. Thumbs down to them for having such an outdated answer to a very relevant question:

How much power/money is used by keeping a F@H running 24/7 on a computer?

Roughly, a CPU uses about as much power as a 60 watt lightbulb. Here's a report on computer power management from Lawrence Berkeley goverment labs, and there are other referencs on the web you can find. Although power supplies on most computers are rated at 250 watts, average usage is much lower. On average, a Pentium-type computer uses between 45-70 watts (I've read various different sources on this) while it is on. If the computer has no idle mode, it will use the same amount of energy whether it is running a program or not. If it is on idle, it will comsume around 25 watts. So, the daily difference between off and running F@H is about 24x(45 to 70) = 1.1 to 1.7 kWh. At $0.14 per kWh ( from PG&E here in California), this works out to about $0.15 to $0.24 per day, or perhaps $6 a month. The difference between an idled computer and one running F@H would be closer to $4 a month - and if the computer was already being used 8 hours a day, it would be closer to $3 a month.

In general, lighting and climate control use a much larger share of household power than computers do. So the best bet for cutting costs and conserving energy would be to turn off lights, turn off your computer monitors (which use more power than a CPU), and turn down the heat. And keep folding :)

[Tawcan]

This is from climateprediction. It's kinda out of date too I guess...

Won't all those computers left on for 24 hours a day have a detrimental impact on the climate system?
Assume a computer running 24hrs/day requires, on average, 50W of power. If 100,000 computers join the climateprediction.net project, the project will require 5,000kW of power. There are 24 hours in a day, so each day the project will consume 120,000kW-hrs, or 432,000,000kJ of electrical energy.

That's a big number, so let's try and put it in perspective by calculating how much energy is necessary to boil water for a cup of tea. Let's use a tiny bit of physics to do it. Assuming a specific heat of water of 4.19 kJ/(kg-K), 0.237kg/cup of water, a necessary temperature rise from 20 degrees Celsius to 100 degrees Celsius, and that only one cup of water is boiled for each cup of tea, then about 80kJ/cup of energy are necessary (assuming our kettle is 100% efficient). This means that running the climateprediction.net project for one day is equivalent to boiling water for 5,400,000 cups of tea!

Is five and a half million cups of tea a lot? According to the Tea Council, some 37 million people in the United Kingdom drink, on average, 3.4 cups of tea per day. That's nearly 126 million cups of tea per day in the UK alone!!!

Each day, about 23 times more energy will be spent boiling water for tea in the United Kingdom than would be used by the computers involved in the climateprediction.net project. More seriously, a rough calculation suggests that 100,000 computers running 24hrs/day for one year at a power consumption of 50W will contribute approximately 0.0001% of the total amount of CO2 generated in one year. This is not an insignificant amount, but seems (to us) a worthwhile investment to better understand the climate system.

Assuming you are convinced this experiment needs to be done, there are basically two options: to buy a hangar-full of PCs and run it ourselves (not even an option right now, since the climate research community doesn't have the resources); or to recycle spare CPU out in the community, as we propose to do under the climateprediction.net experiment. Since the main environmental impact of a PC is in manufacture and disposal, not the power consumed in running it (never mind the air-conditioning costs and visual impact of that hangar on some innocent rural community), environmentalists will, we hope, approve of our strategy.

Nevertheless, this would be an interesting topic for further discussion, and we warmly invite you to go to the interactive parts of this portal and make your voice and/or opinion heard in the climateprediction.net community. See also the question on joining the user community further down.

[goobee]

The calculation by Stanford is unreliable and they should be ashamed for keeping it up. The average distributed project junkie uses middle to high end computers, not Pentium 133s. :rolleyes:

The price of electricity is not charged on a linear basis but on a tier basis. After you've exceeded your baseline limited, your per kilowatt charge increases to a higher amount.

Modern processors such as the Athlons suck more power than most people realize. For example, I have 3 duallie boxes on a 25 amp circuit - if I run anything else on that circuit, the breaker blows. So much for the 60 watt light bulb analogy.