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Five PC Power Myths Debunked
Posted by
timothy
on Fri Dec 12, 2008 09:35 AM
from the ones-much-easier-on-wires-than-zeros dept.
from the ones-much-easier-on-wires-than-zeros dept.
snydeq writes "Turning off PCs during periods of inactivity can save companies between $25 and $75 per PC per year, according to Energy Star, savings that can add up quickly for large organizations. Yet most organizations remain behind the times on PC power management, in large part due to common misperceptions about PC power, writes InfoWorld's Ted Samson, who outlines five PC power myths debunked in a recent report from Forrester, ranging from the energy savings of screen savers, to the energy draw of powering up, to the difficulties of issuing patches to systems in lower-power states."
Related Stories
[+]
Companies Waste $2.8 Billion Per Year Powering Unused PCs 348 comments
snydeq writes "Unused PCs — computers that are powered on but not in use — are expected to emit approximately 20 million tons of CO2 this year, roughly equivalent to the impact of 4 million cars, according to report by 1E and the Alliance to Save Energy. All told, US organizations will waste $2.8 billion to power 108 million unused machines this year. The notion that power used turning on PCs negates any benefits of turning them off has been discussed recently as one of five PC power myths. By turning off unused machines and practicing proper PC power management, companies stand to save more than $36 per desktop PC per year."
[+]
Why IT Won't Power Down PCs 576 comments
snydeq writes "Internal politics and poor leadership on sustainable IT strategies are among the top reasons preventing organizations from practicing proper PC power management — to the tune of $2.8 billion wasted per year powering unused PCs. According to a recent survey, 42 percent of IT shops do not manage PC energy consumption simply because no one in the organization has been made responsible for doing so — this despite greater awareness of IT power-saving myths, and PC power myths in particular. Worse, 22 percent of IT admins surveyed said that savings from PC power management 'flow to another department's budget.' In other words, resources spent by IT vs. the permanent energy crisis appear to result in little payback for IT."
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a PC actually wrote this article (Score:5, Funny)
Re:a PC actually wrote this article (Score:5, Funny)
I'm sorry Dave. You can't do that.
Parent
Re:a PC actually wrote this article (Score:5, Insightful)
See, your math is nonsense. Not that it's wrong, its just that you CAN'T combine all those minutes to get something productive. The minute I save each day isn't going to make a difference to the next day.
Parent
Re:a PC actually wrote this article (Score:5, Interesting)
"What about the extra 5 minutes that it takes me to open up my email, and all the other programs that I was working on the previous day?"
I don't know you, but my session just opens up all the apps I work on on their desired states; it all takes just a few seconds and no human intervention:
*Desktop#1: e-mail, opened on the main entry folder
*Desktop#2: a browser with my "everyday work" sites (like the systems monitoring console and the systems and operations documentation web) and my "morning" sites (like some news sites, Slashdot included), one per tab.
*Desktop#5: some terminals conecting to some "key" servers I then to log into everyday
*Desktop#6: another browers with my "administrative" sites (like the timeing and ticketing web app), again, one per tab
I tried openning the session to yesterday's state but after few days, I found better to start with a clean known state instead.
Oh, yes: my desktop manager is KDE, which you can use on all unix-like systems, in case yours doesn't allow this kind of customization and you want to give it a try.
Parent
Re:a PC actually wrote this article (Score:5, Insightful)
That's why you use WoL to boot the system one hour before employees arrive, do a virus scan, check for updates, or other maintenance tasks.
1 hour is generally enough time for updates and virus scan. Employees come into a machine ready to go, you get regular maintenance and everybody's happy.
Parent
Re:a PC actually wrote this article (Score:5, Interesting)
This is what I did in my last position, and it worked well. I was due to come in at 8:30am, so I turned off the computer when I had to go (or scripted a time for it to turn off if there was a process running), and configured the BIOS alarm to wake the computer up at 7:30am every weekday. Worked every time; the only thing I had to do was log in, but since credentials are cached, all of my background programs were started before I even had to type my user name.
The only caveat is that I can't do this for Thinkpads for some strange reason.
Lots of people are intolerant of even rebooting their computer during the day, but don't realize how infuriated they would get when their computer starts acting up because they didn't restart. Unless one works at a software development house, I doubt *most* users need their PCs on 24/7.
Then again, I think I'm being naive for a repetitive intern.
Parent
Re:a PC actually wrote this article (Score:5, Funny)
You must have missed the posts from a few days ago...
It's been determined that step 4 is "ask for a government handout/bailout."
Parent
Re:a PC actually wrote this article (Score:5, Insightful)
That step is only applicable if you are super rich. These days only billionaires get welfare.
Parent
The units! (Score:5, Insightful)
Energy is kWh power is kW. "Energy at a rate" is power, and should be in kW not kWh.
Re:The units! (Score:5, Funny)
What do you mean, an european or an african kW?
Parent
Typo? Pshaw! (Score:5, Informative)
Of the four instances in which watts were referenced (directly or in compound units), three are completely boneheadedly wrong:
They should be:
You *can't* call it a typo when they are perfectly backward in three out of four incidents. And you can't call it "They just got it backward..." when they got it right once. You must conclude, therefore, that they have almost no grasp whatsoever of units.
Parent
Re:Typo? Pshaw! (Score:5, Funny)
It makes perfect sense. I just read it to mean that power usage increases every hour by 89 watts, and that by the time it's been left on overnight for 16 hours, the power usage of an average desktop has increased to 1.42kW. (If you think I'm joking, do the math -- that can't be a coincidence ;-))
This kind of growth of power usage means it is extremely important to turn off your PC every night, otherwise by a month later the power consumption will be approximately 64kW, which will probably result in it melting through your desktop unless you have very good cooling.
Parent
Re:Typo? Pshaw! (Score:5, Funny)
This kind of growth of power usage means it is extremely important to turn off your PC every night, otherwise by a month later the power consumption will be approximately 64kW
64kW should be enough for anybody.
Parent
Re:Typo? Pshaw! (Score:5, Interesting)
Unit errors are generally a sign in technical fields that a report hasn't been well thought out. No engineer proofreading this would have missed such a blatant error which means that an engineer didn't proofread it.
If an engineer did not proofread it, an engineer did not likely do it. Therefore, the content of the article was likely done by an incompetent hack and charging $279 for the report is a way of hiding the fact that it was written by a hack.
Parent
Re:The units! (Score:5, Informative)
Parent
Re:The units! (Score:5, Funny)
So does that mean on my last trip I drove 720 MPH?
Parent
Re:The units! (Score:5, Funny)
You are complaining about scientific unit names to Slashdot? Have you seen some of the names for Linux apps?
Parent
Re:The units! (Score:5, Interesting)
If you need a convenient size, that's what the prefixes are for. A MJ is as conveniently sized as a kWhr. Whr is more convenient in some applications for calculating energy used over time, so it's a reasonable thing to use there.
Miles per gallon is a silly set of units to use. Metric units would be nice, but have little practical benefit for most usage cases (unless we were to switch to selling liters of gas and marking roads in km, but that's unlikely). The problem is that miles per gallon is backward. It should be gallons per mile (or 100 miles something similar for convenient scale). Why? Distance is the independent variable, not the dependent one. You might want to know how many gallons you'll use on a 200 mile trip, but it's unlikely you want to know how far a trip you can go on with the 8 gallons left in your tank. Furthermore, it's not convenient for comparing operating costs either. You drive your car a certain number of miles per month, not a certain number of gallons. If I want to compare three cars that get 20, 30, and 40 mpg, the cost savings between the first two is bigger than between the last two -- despite the same change in the number. Basically, every time you use mpg, you have to do a division -- not the hallmark of a convenient unit.
Parent
Winter (Score:5, Funny)
In the winter I leave my computers on. I don't think I am "loosing" any energy that way since it's used to heat my house.
Re:Winter (Score:5, Interesting)
The EPA awarded my company with one of their top awards this year for improvements to our facility, and energy efficiency. Overall we cut energy consumption 50%, but also used our energy more smartly, including a dedicated ducting system from our server room to the building entrances. We calculate that our servers put out between 8,000 & 12,000 Btu an hour. Most of our overnight heat now comes from the servers (which have to be on 24/7 for off site access), and we've reduced our server air conditioning loads by 80% annually. We're now beginning to implement this change into bank designs.
In almost every application, it's ideal to shut off computers when not in use, but there are some business based situations where it makes sense to better harness waste heat from electronics, instead of fighting it with energy intensive air conditioners.
http://www.energystar.gov/index.cfm?c=sb_success.sb_successstories2008_johnsonbraund [energystar.gov]
Parent
Re:Winter (Score:5, Funny)
My dorm room used to get so goddamn hot because of this.
Mine used to get hot because of the girls. Aaaah! Wishful thinking...
Parent
Re:Winter (Score:5, Funny)
Mine used to get hot because of the girls.
That will happen when they show up with torches and pitch forks.
Parent
Re:Winter (Score:5, Informative)
Depends on where you live and what you're heating. Ignoring regional variations in costs and heating needs, a natural gas forced-air system will heat the entire house, requiring substantially more money than electric radiators, which are per-room.
Combine this with places where electricity is remarkably cheap (e.g. large hydro works) and natural gas is expensive (e.g. all imported), and you are better off heating with electricity. Even if you live in an area with cheap natural gas, electric radiators allowing you to heat only the spaces you're using may end up saving you money over heating a whole house at night to keep the temperature toasty in two occupied bedrooms. This is especially true in Mediterranean climates, where natural indoor temperatures remain above 12 C even in the winter, thus requiring a comparatively small "bump" to hit the desired 20-22 C range.
In any case, waste heat generated by electronics is salutary, so long as the electronics are being used for their primary purpose as well.
Parent
Re:Winter (Score:5, Interesting)
None of that justifies heating with electrical resistive elements. There are two flaws to your argument:
1. You mix using gas with whole-house heating.
These shouldn't be mixed. You can have a whole-house gas furnace, or you can have gas units (or a gas fireplace) in critical rooms. Likewise, you can have a whole-house electrical system, or one per room. Or, you could have electronically-controlled baffles for your air distribution, which cost relatively little but allow you to direct airflow to only specific rooms at specific times of day.
2. You are advocating resistive heating as efficient.
Resistive heating can be 100% efficient: every watt you purchase becomes a watt of heat in your room (until it leaks out the window).
But that's not efficient for heating. A heat pump uses the watt of energy you purchased to perform work, moving heat contained in the colder, outdoor air to the warmer, indoor air of your house. The net effect is that each watt you purchase can translate to 3-4 watts of heat in your room. While clearly not accurate syntax, a head-to-head comparison would call such a heat pump 300 to 400 percent efficient, significantly better than the mere 100% your resistive heater generates.
Then you can use electronic baffle control to direct the heat just to bedrooms at night, and result in an overall system that is quite efficient and doesn't rely on one particular fossil fuel to function.
disclaimers
My house heats with natural gas, and we have an electric heat pad on our bed for cold nights. In other words, we do exactly the things I advocate against. That doesn't make them right, it just makes my actions wrong.
Parent
Sorry I can't turn off my PC (Score:5, Funny)
>>>"Turning off PCs during periods of inactivity can save companies between $25 and $75 per PC per year"
How am I supposed to download last night's episodes of Smallville and Supernatural if I have my PC turned off during the day? Jeez. Insensitive clod. ;-)
Re:Sorry I can't turn off my PC (Score:5, Interesting)
NSLU2 + bus-powered USB drive + debian + torrentflux-b4rt
Max 10W drain, with one drive it's nearer 5W. Add in ushare and you have a low energy box that has a web interface for torrenting stuff and can stream the results to your xbox. All for $60 (or so) and the price of the drive.
Parent
Not just power issue (Score:4, Insightful)
Re:Not just power issue (Score:5, Insightful)
So suspend.
Parent
Re:Not just power issue (Score:5, Informative)
Well 15 minutes of power on and power off is a bit exaggerated (unless you really misconfigure linux). Normally for most business PC it takes about 1 minute to power on and power off doesn't need to be counted as you can perform this action without you actually there you hit shutdown and it does its thing.
That being said...
>>> (20.00/60)*5*(48+(4/5))
80.0
Assuming 20.00 an hour average wage (40k per year)
We divide this by 60 to give the rate per minute.
Multiply this by 5 for the five work day week.
Then multiply it by 48 and 4/5 for fifty work weeks (2 week vacation) a year and subtract one extra week and a day for holidays (New Years, Memorial Day, Independence Day, Labor Day, Thanksgiving, Christmas) .
So in theory it is more expensive to power on every day...
However the human factor is not factored in even for your 10 minute days of inactivity. At the beginning of the day most people are not at 100%. They will power on the computer, take off their jackets, get some coffee, put their lunches in the kitchen, greet some people, clean their desk up a bit. Also any loss productive during 10 minutes can usually be made up.
So you might as well power off at the end of the day and save some power and be better for the environment.
Parent
Thats why you don't turn off, you sue S3 suspend. (Score:5, Informative)
Any modern PC can S3 suspend.
S3 suspend cuts power use by 95% and the PC resumes *INSTANTLY*.
I can S3 suspend my laptop and have it run off the battery for over a week - open it up and I am back where I left off in about 2-3 seconds.
There is no argument against having an IT policy MANDATING S3 suspend. Hell you can even automate it to do it by default every day at 6 PM unless the PC is in use (easily checked by screensaver APIs).
Parent
Re:Thats why you don't turn off, you sue S3 suspen (Score:5, Insightful)
Not with Windows or several Linux Distros. I would say at least 25% of the time the machine will not return and must be rebooted anyway.
Parent
Re:Thats why you don't turn off, you sue S3 suspen (Score:5, Insightful)
Any modern PC can S3 suspend.
S3 suspend cuts power use by 95% and the PC resumes *INSTANTLY*.
I can S3 suspend my laptop and have it run off the battery for over a week - open it up and I am back where I left off in about 2-3 seconds.
There is no argument against having an IT policy MANDATING S3 suspend. Hell you can even automate it to do it by default every day at 6 PM unless the PC is in use (easily checked by screensaver APIs).
I still have issues suspending/waking computers. Generally it works fine... But sometimes you run into odd issues.
One client we support has a piece of software that hates waking from suspend. Pitches a huge fit. All sorts of errors.
And I still have problems with some computers/OSes that really should handle S3 just fine simply choking on it. Won't resume reliably or whatever.
The real problem I have with power saving options is rolling out the settings consistently across multiple computers. Last time I checked (and it has been a little while since I checked, so I could be wrong) there was no way to push out power settings with a GPO. Sure, you can set screensaver options... Turn off the monitor or something... But that doesn't get you a suspended computer. You can set options on the individual computer, in their motherboard settings... But that isn't easy to update/change across a network. You can throw together a pile of scripts to shut down machines...maybe try to use wake-on-LAN to power them back up in the morning...
I'm not saying it can't be done. And I'm not going to say that you can't save any power by doing it. But there doesn't seem to be a simple way of managing these settings across a network yet. It still seems that power management is a hacked-together feature that was tacked on after the fact.
I'd love to be able to push out a group policy that made all the computers on my network suspend after an hour idle.
Parent
Re:Not just power issue (Score:5, Funny)
If you spend 10 mins per day turning you pc on and setting up your work environment, and 5 mins closing everything, the cost of your time spent on this task will negate $25 saved ten times.
Takes you five minutes to close everything? Jeez, my users just flip the button on the power strip. Log off and shut down in 3 seconds or less...
Parent
Re:Not just power issue (Score:5, Insightful)
Good insight. With my salary a 15 minute loss would be $3000 lost per year. However shutdown time is not something I have to sit and watch, and it doesn't really take 10 minutes to bootup (more like 5), so that reduces the loss to one-third my original calculation - just $1000.
That does exceed the $25 in power savings.
This is why so few people choose energy efficiency. The money saved does not compensate for time/wages lost. Perhaps when oil hits $1000 a barrel, then people will be more mindful, but for now energy is just too cheap.
Parent
Do they care? (Score:5, Insightful)
From my experience with some corporations, the way it works is more like:
1. The left hand doesn't know, and doesn't want to know what the right is doing. If your department can save $10 bucks, but it costs everyone else 10 million in workarounds and lost productivity, who cares? You're the greatest anyway.
2. Any attempts to rein in waste and such effects, just introduces one more layer who'll get their bonus for making you buy a tool that costs $10 less, but where you spend 100,000 more in salaries to do the same job. Occasionally it introduces a masked form of corruption too: they get more bonus for buying a $1000 pencil at 50% discount, than a normal one at 5% discount. In the former case they "saved" $500 per pencil. They're that great.
3. Don't underestimate interdepartment power games. Making you curse and waste more effort for implementing my hare-brained cost-cutting schemes, is the gretest achievement some people can get. It's me having power over you. For some people it's a powerful drug.
4. Theatre. Being seen as doing something beats doing the right thing. You can see that at all levels and in all domains: security theatre, cost-saving theatre, etc. Being seen as being teh great green saviour can beat actually saving money.
5. In that vein, beware the new boss who just has to piss on everything to mark his new territory. The higher level, the more dangerous. These guys _have_ to show that they changed something. It shows vision, leadership, etc. So he'll cheerfully make an actual loss, just so he can put a good leadership and vision theatre.
6. There's a whole caste of people across the pyramid whose goal in life is to not rock the boat and not be responsible for anything. It's better to comply with a dumb rule (even one that wasn't supposed to apply to your situation or domain) than to have anything be your personal decision, and responsibility if it fails. Applying someone else's rule is like having a papal indulgence: whatever goes wrong, you're not the one who'll be punished for it. These fine guys and gals would mindlessly enforce even turning off the computers _during_ work hours, if that's what the rules say.
7. Don't underestimate the effect of rewarding failure. E.g., see the thing about "saving" money by buying a disproportionately _more_ expensive thing. E.g., in some places, keeping the people under you from doing their job can mean needing to hire more people, and if you get enough of them you get a promotion. E.g., being the guy who dumbly applies rules without thinking, cam actually get one a promotion or at the very least it's often enough to not get demoted or phased out.
So, yes, I've seen places where they paid consultants in the range of thousands per hour, but would rather pay those to twiddle their thumbs for a quarter of an hour while a baroque configuration starts, than "waste" cents on leaving that computer idle over night.
Parent
Lets see (Score:4, Insightful)
Turning off PCs during periods of inactivity can save companies a substantial sum. In fact, Energy Star estimates organizations can save from $25 to $75 per PC per year with PC power management
Lets assume each PC has a user who is paid at least $25000 per year. We can clearly see the savings on the cost of that employee and thier PC setup caused by this are negligable.
he Forrester report does acknowledge that end-users have very little patience for downtime. However, it suggests that "potential user complaints can be mitigated by communicating the positive financial and environmental benefits of PC power management."
Complaints or not the company is paying for any user downtime.
I felt a disturbance in the Force . . . (Score:5, Funny)
Word (Score:5, Informative)
Quoted from the article (Score:5, Insightful)
"potential user complaints can be mitigated by communicating the positive financial and environmental benefits of PC power management."
Now that just plain hilarious.
My favorite: the black display (Score:4, Insightful)
No thanks to the spam (Score:5, Insightful)
Learn how to save $25 to $75 by purchasing the $279 dollar report that the article is hawking. No thanks. This article has no business even being on Slashdot. It isn't news, it is an advert.
Bad economics (Score:5, Informative)
1.42kw for the computer to run overnight has a cost of around 10 cents to the company.
Waiting 5 minutes for your PC to boot at the federal minimum wage of $6.55 per hour has a cost of around 55 cents to the company.
It costs the company at least 5 times as much to have you boot your PC in the morning as it does to let it run overnight.
Re:Bad economics (Score:4, Insightful)
You're making the assumption that people work continuously whenever their computer is on, and do no work when it is off/starting up.
Parent
Re:Bad economics (Score:5, Insightful)
You're making the assumption that people work continuously whenever their computer is on
I'm also assuming that you earn minimum wage. ;)
Parent
Re:Bad economics (Score:5, Funny)
How is this insightful?
I can't imagine. I meant it as a double-entendre: I pointed out that most office computer users are making far more than minimum wage, hence the ratio is a lot higher that 1:5. At the same time I implied that you, specifically, were making minimum wage. I was hoping for a "funny."
Parent
Re:Bad economics (Score:5, Insightful)
Any big IT department is also pushing out patches at night when the computer is on.
The cost of a year of leaving the computer on (to get those patches) overnight is $75.
How much is an infected and screwed up computer costing the company (because it didn't get patched quick enough)? Maybe half a day of IT guy's time? Maybe more... depending.
There's lots of places companies can save some money by being more efficient, I think I'll look elsewhere for bigger gains first before compromising the ability to push patches during hours the office is closed.
Heck, a "quit smoking program" for the company will probably save a whole crapload more in sick time, "smoke break" time and health insurance costs than electricity used the PC ever will.
Parent
Saving power, but increasing frustrations (Score:4, Interesting)
I agree that you can save power with low-power (standby) modes on your PCs.
However, as a network admin as a mid-sized company, I also have seen loads of frustrations where PCs (both laptops and desktops) don't come out of power save mode cleanly, requiring a reboot. Wake-on-lan is also a great concept, but also pretty buggy (again...in my limited experience trying to implement it). We also have issues where our client systems are using network applications with license pools (e.g. database applications or CAD packages). When a user leaves one of these applications open, then the PC goes into power save mode...it really freaks out when it comes back out of power save mode since the license server thought the system had released the license, but the client still thinks it has a licens in use. This situation usually results in the need to reboot, which frustrates the users to no end.
I set all of our PCs here to lock and send only the monitor into low-power mode after 20 minutes or so. Then we don't have the problems with coming out of power save mode and having locked up or frozen applications (especially the aforementioned network applictions), but still save a good bit of power by allowing the monitor to be turned off automatically.
Anyone have any idea what percentage of power is used by the monitor versus the PC itself? I don't have a clue, but I'd bet it's a pretty good percentage. There's also probably a big difference between CRT monitors and LCD monitors...again, my gut feeling, but I can't cite any numbers.
Later,
JS
Bad News For Vista (Score:5, Funny)
FTA: Modern computers are designed to handle 40,000 on/off cycles before failure
With all the reboots required, that means I am limited to three Vista reinstalls?
I love this part of the text (Score:4, Insightful)
"Myth No. 5: My PC users will not tolerate any downtime for power management.
The Forrester report does acknowledge that end-users have very little patience for downtime. However, it suggests that "potential user complaints can be mitigated by communicating the positive financial and environmental benefits of PC power management.""
I love this kind of response. It's pretty much ignoring the problem. PC users will not tolerate any downtime for power management even if you "educate" them. This is trying to wave the problems away and it won't work.
Re:[citation needed] (Score:4, Insightful)
Parent