PB is trying to work out how much carbon her companies idiotic policy of leaving there computers on 24 hours a day 365 days a year is causing

This is her submission


The following are based on figures found at http://www.greenlivingpedia.org/Green_facts
and are based on a basic computer unit using 65 watts of electricity, and a 17 inch flat panel LCD monitor using 35 watts of electricity.

I have also based the figures on an average 8 hour work day and standard 5 day working week. Thus,

8 hours per day of use.

14 hours per day not used (week day)

+48 hours not used (weekends)

14 x 5= 70 hours (week days)

70 + 48 = 118 hours per standard week of non–use.

52 weeks per year at 118 hours of non use per week = 6136 hours of computers being left on unnecessarily.

If we assume that every employee of the ****** group switched off their monitors before leaving for the day, this would equal:

65 watts (basic computer unit, not including monitor) x 6136 hours = 398,840 watts per computer, per year.

398,840 watts divided by 1000 = 398.840 kilowatts (Kws)



Taking every computer in the ******* group, which is approximately 10,100, into consideration, this would equal :


this is where she has gotten to and has confused herself and aggrivated me in the process.

If you can work it out and post it here (With sources please) She would really really appreciate it, as she is presenting this to the state manager of her company monday morning :eek:

I HAD worked this out for her but she has compleatly ignored all of my calculations :mad: shown below:

Best Answer - Chosen by Voters
A typical business desktop with integrated graphics or low power video card would consume about 75W at idle. A 17 inch LCD would draw about 30 watts.
So, energy wasted in an hour is about 105 watt-hour or 0.105 kW-hr.

In stand by mode, PC is just powered by +5V SB of power supply. This voltage rail is usually rated at 12.5 -15 watts MAX.
Actual standby power draw is less than 10W. LCD consumes 1 watt on standby mode.

http://www.silentpcreview.com/article752-page4.html

source:http://answers.yahoo.com/question/index?qid=20080214033141AALl7Al&show=7


14 hours per day not used (week day)
+ 48 hours not used weekends
+ 10 public holidays aproximatly (240 hours)

14*5= 70 hours

70+48 =118hours per standed week


50 weeks at 118 hours per week equals 5900 hours (plus 2 extra weekends and the public holidays)


equals a grand total of 6236 Hours

Now we take the above calculation of 75w per hour

6236*75 = 467700W or 467.7kW FOR ONE COMPUTER

Now there are 10,099 computers

10,099 * 467.7kW= 4,723,302.3kW

Now even taking natural gas as the source of your power that is 0.55kg of Carbon dioxide(cO²) per kilowatt hour (kWh)
(source: http://www.dkacoolmob.org/climateChange.html)

So that would equal 4723302.3 * 0.55kg

so your policy is producing aproximatly 2,597,816.265 Kg of CO2 per year



Please tell her i was right:p

oh and before someone responds with "gobal warming is a myth" its irrelivent. The company in question has in there charter that they will reduce carbon emissions and if they dont they have to pay a large fine.

Isn't the reason many companies do this that turning computers on/off puts more wear and tear on them than just leaving them on all the time? And how much power does a computer in "sleep mode" use, anyway?

Isn't the reason many companies do this that turning computers on/off puts more wear and tear on them than just leaving them on all the time? And how much power does a computer in "sleep mode" use, anyway?

Turning them off then on again doesn't take more energy than leaving them on.

Turning them off then on again doesn't take more energy than leaving them on.
Yes, but is the constant on/off harder on the computers than just leaving them on most of the time (but in sleep mode)?

no mad it doesnt. You want to hear there reason, because they want to do updates at night and are to lasy to press the tab which says "automatically turn computer off after update"

thats there ONLY reason for this policy

4,380.000 MWH ~= 338,000,000 Pounds of CO2 for thermal power plants.

You can auto-hibernate computers...the monitor is usually goes to sleep mode at a preset time. Newer computers are getting smarter in this regard....

no mad it doesnt. You want to hear there reason, because they want to do updates at night and are to lasy to press the tab which says "automatically turn computer off after update"

thats there ONLY reason for this policy
Are you sure:
For years, many pundits have claimed that continually shutting down and restarting your computer more quickly wears out the power switch, drive motors, and other components.

Most importantly, according to advocates of the leave-it-on theory, starting up a cold computer puts extra stress on the read/write heads inside the hard drive.

Some PC users also worry that the stress of heating up components and then letting them cool down again can cause premature failure. It’s true that some PC parts expand as they warm and then contract as they cool; repeating this cycle several times throughout the day may very well cause more wear than leaving a computer on all the time.
How about a middle ground choice:
If a complete shutdown doesn’t appeal to you, you can also use your system’s Hibernate or Standby modes, which consume little electricity, yet let you restore your computer to a ready state much more quickly than a cold startup.
http://www.smartcomputing.com/Editorial/article.asp?article=articles/webonly/techsupport/04w10/04w10.asp&guid

kmguru can you please post your source. For starters i need it in KG's (this is an australian company not an american or british one). More importantly she cant just walk in and say "this is the answer". Her boss would rightly ask "how did you get that number and whats your source" and she couldnt answer him

Mad as i said there reasoning has nothing to do with wear and tare and ONLY to do with the updates thing. I know this because during the meeting she actually asked that question and thats what she was told.

Also even if this is the case wouldnt $75,0000 per year in fines (plus the actual cost of the electricity) be greater than the cost of replacing a harddrive or 2?

Do a Google with ---500 MW coal plant will produce 338000 tons of CO2--- you will get many hits. Then convert the power to a full year and tons to pounds and then Kg.

Kmguru im seriously not being lasy about this. I have spent the last 2 days trauling through google trying to find the conversion.

I just sent the work to both the leader of the greens and the climate change minster to see if they could surplie the infomation because i cant find it anywhere. Its made even more dificult because it depends what state you are in as to how much emmissions are relaced. Some states use hydro or gas or coal fired power so its dam near impossable to work out a country wide amount. This is made compleatly impossable as i dont know the break down of the computers by state, all i know is the total amount accross the company.

Oh and on a side note to what mad said, i was talking to my father and he was saying that his company (one of IBM's subsiduaries) used to leave there computers on constantly for fear of componante degritation but they have stoped doing it now. The only thing that runs at night are the servers with the databases which are actually used at night (like the vicroads database and the telstra databases ect)

I guess i will just have to wait to see what penny wong's staff send me back

A quick note on units.

The power consumption of a computer (e.g. 65 W) is measured in Watts (W). 1 Watt is 1 Joule of energy per second.

If you multiply the power by the number of hours the computer runs for, that gives you an energy measured in Watt.Hours (Wh). The usual measure used is kiloWatt.hours (kWh), where 1 kilowatt is 1000 Watts.

One thing that might sway the company is to work out the dollar cost of the energy, as well as the carbon emissions. Find out the rate per kilowatt hour, and multiply by the kilowatt hours of wasted time.

Isn't the reason many companies do this that turning computers on/off puts more wear and tear on them than just leaving them on all the time?

No. Most companies don't have a policy on switching desktop computers off. They simply haven't considered the issue.

And how much power does a computer in "sleep mode" use, anyway?

More than it uses when it is off.

Yes, but is the constant on/off harder on the computers than just leaving them on most of the time (but in sleep mode)?

Not unless you're switching them on and off every 5 minutes. Doing it once a day won't cause any significant wear and tear over the average life of a desktop computer.

For years, many pundits have claimed that continually shutting down and restarting your computer more quickly wears out the power switch, drive motors, and other components.

Intuitively, this seems wrong. A hard drive, when it is switched on, is constantly spinning. If anything is going to wear out the motor, leaving it on continuously will do the job.

Most importantly, according to advocates of the leave-it-on theory, starting up a cold computer puts extra stress on the read/write heads inside the hard drive.

If this is in fact true, the "extra stress" would be utterly negligible over the typical lifetime of the drive.

Some PC users also worry that the stress of heating up components and then letting them cool down again can cause premature failure. It’s true that some PC parts expand as they warm and then contract as they cool; repeating this cycle several times throughout the day may very well cause more wear than leaving a computer on all the time.

Again, even if true this would be negligible over the average lifetime of a machine.

If a complete shutdown doesn’t appeal to you, you can also use your system’s Hibernate or Standby modes, which consume little electricity, yet let you restore your computer to a ready state much more quickly than a cold startup.

"Standy" is different from "Hibernate", in that in standby mode the computer is still on, whereas in hibernate mode the current state of the system is written to disc and the computer shuts off.

Standy is marginally better than fully on. Hibernate is just as good as off, but it takes longer to put the machine into hibernate mode than to simply shut it down.

james if i made a mestake im not sure where your saying it is im sorry
Also the definition i found said that kWh was a RATE not a mesasurment (not sure if this is what your saying or not)

I mean that a 1kW device uses 1kW an hour so that is 1kWh. If this is wrong please tell me because thats how i explained it to PB and what she is about to tell her boss:o

Also the definition i found said that kWh was a RATE not a mesasurment (not sure if this is what your saying or not)

I mean that a 1kW device uses 1kW an hour so that is 1kWh. If this is wrong please tell me because thats how i explained it to PB and what she is about to tell her boss:o

1 kilowatt is 1 kilojoule of energy per second. Thus, a kilowatt is a measure of the rate that energy is used (i.e. energy per unit time). Energy per unit time, by the way, is what physicists call power, and the Watt (or kilowatt) is the standard unit of power, while the standard unit of energy is the Joule.

If you multiply power by time you get energy. Since the kilowatt is a unit of power, if you multiply it by a number of hours you get an answer in kilowatt.hours, which is an energy unit, as I tried to explain before.

What you pay for when you pay a "power" bill is actually the amount of energy you have used, and not the rate at which you used the energy. That is why charge rates are quoted on your bill in cents per kilowatt.hour.

In summary:

Unit of energy: Joule.
Unit of power: Watt. (1 Watt = 1 Joule per second. 1 kW = 1000 W.)
Another unit of energy: Kilowatt.Hour

1 Kilowatt.hour = (1000 W)(1 hour) = (1000 W)(3600 seconds) = 3600000 Joules = 3600 kilojoules of energy.

You guys are all much smarter than me so I have nothing to add to this thread other than to say that CO2 is good for the environment.

Green house = happy plants.

Photosynthesis = happy humans.

Standy is marginally better than fully on. Hibernate is just as good as off, but it takes longer to put the machine into hibernate mode than to simply shut it down.My computer goes into hibernate when the battery gets low. I'm pretty sure you can set the desktops to go into hibernate after a certain amount of inactivity. The advantage is, it starts up a lot more quickly than a complete re-boot.

My computer goes into hibernate when the battery gets low. I'm pretty sure you can set the desktops to go into hibernate after a certain amount of inactivity. The advantage is, it starts up a lot more quickly than a complete re-boot.

It still consumes power even in sleep mode. The only way to stop that is to turn it off completely.

While the power it consumes in sleep mode is less than when it is actively on, it does still consume power when it is in sleep mode.

For example, say you have a VCR. You turn it off with the remote or by clicking the on/off button on the machine. It is still consuming power, which can be seen quite easily by its display (clock, etc). The only way to stop it consuming power is to turn it off at the wall or to unplug it.

Sleep mode does not equal = power usage. It just means it's using less power than when it is turned on.

so though i got mixed up i still multiplied out the right results?

as for the other debate going on time to bootup its irrlivent. The policy is TOTALLY because they want to do an occasional update overnight and they cant be bothered deciding which nights or clicking the close computer after download tab.

the figures i have found say that it only uses 10% LESS on standby than on and james has already delt with the hibination thing

So basically if they picked a night (say every wed) then they could leave the computers on ONLY on that nigh and then click the close when finished tab and they will cut it down to no un nessary useage at all

because PB brought this issue up they want her to join the green board for her company which makes recomendations on how to save the company money and emissions. As i said this is written into there company charter and they have to pay if they break it so there is already an economic insentive to do things like this. The problem isnt the company as a whole, its the computer department which dont think about anything but themselves.

You guys are all much smarter than me so I have nothing to add to this thread other than to say that CO2 is good for the environment.

Potentially not so good for the continued existence of human beings in the environment, however. Look at Venus.

Potentially not so good for the continued existence of human beings in the environment, however. Look at Venus.
Um, the atmosphere of Venus is 95% CO2 verses less than 1% on earth. Venus also has a much denser atmosphere with an atmospheric pressure almost 100 times that of the earth. Finally, Venus is closer to the sun.

So let's not go overboard on the earth/venus comparison.

madanthonywayne:

Venus is a good example of what happens when a planet has a runaway greenhouse effect. Too much carbon dioxide in the atmosphere can cause such an effect.

So, let's not go overboard in assuming that what is positive for plant life in the short term is good for Earth and human beings in the long term.

Venus is a good example of what happens when a planet has a runaway greenhouse effect. Too much carbon dioxide in the atmosphere can cause such an effect.

So, let's not go overboard in assuming that what is positive for plant life in the short term is good for Earth and human beings in the long term.
Are you suggesting we're on the brink of some sort of runaway greenhouse effect that would turn the earth into Venus? If we assumed all other things were equal, we'd need an increase on the order of two levels of magnitude to achieve Venus levels of CO2. That's not even considering that Venus has a much thicker atmosphere and is closer to the sun.

Furthermore, the earth is thought to have once had an atmosphere with vastly more CO2 than now and no "run away" greenhouse effect was set in motion. Quite the contrary.

Finally, our levels of carbon output will continue to increase for a while, that's inevitable. But it's also inevitable that they will eventually go back down as we use up all the readily available fossil fuels and switch to something else. So chill out, the problem (if there is one) will take care of itself. Just like the problem of excessive horse manure on city streets took care of itself.

But it's also inevitable that they will eventually go back down as we use up all the readily available fossil fuels and switch to something else. So chill out, the problem (if there is one) will take care of itself. And we hope the human population will come through that several hundred year bottleneck in reasonable shape, with agriculture and all that good stuff. It won't necessarily be a smooth ride.

can i just point out that as i said in the operning post. IM NOT INTERESTED IN A DEBATE WETHER GLOBAL WARMING EXISTS!!!!!!!!!!

The company in question has said in there charter that they wish to reduce CO2 emissions. This policy wasnt just going to cost them in the electricity costs but they have to pay a $75,000 fine for breaching that charter agreement (this year, it gets even more expencive for them next year). This was purly about the mathmatics, the actual emmissions and the economic cost to the company.

For those of you who dont belive in climate change thats your decision and i could care less. Pretend these are rainbows or something we are talking about because as far as the company is concerned it DOES exist.

can i just point out that as i said in the operning post. IM NOT INTERESTED IN A DEBATE WETHER GLOBAL WARMING EXISTS!!!!!!!!!!
Geez, Asguard, sorry. I just couldn't resist!
:o

sorry but as i said i made this thread specifically to get help on a very specific thing. I dont care if you guys turn my debate on poligamy into a debate on homosexuality or a political debate from one country to another. This thread however isnt a debate on global warming and i REALLY dont want to have to dig though hundreds of pages to find the answers PB needs:p

That being said it wasnt aimed at you my friend, it was aimed at anyone reading because if i didnt say it when the thread is just starting up i would come back tomorow and everyone else would have joined in on that side because its a more "sexy" debate than wether the calculations were correct or not

Sorry for getting grumpy my friend