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Do Any Companies Power Down at Night?
An anonymous reader writes "My Health Sciences Campus has about 8,000 desktop computers, and on any given night about half of them are left on. I know this because I track all the MAC addresses in case there is a virus outbreak. Aside from the current fad of 'being green', has anyone had any success in encouraging users to power-down at night? You could potentially eliminate running bots, protect yourself from the next virus outbreak, keep your data safe, etc. Do security concerns and power consumption issues matter enough to do this?"
I won't go into the green topic. But here's a suggestion: Why don't you just shut down ethernet switches and routers at night? That would be just as effective at halting propagation of virii/bots, and would be much easier to effect.
:-)
And improved employee morale could result as well, since what would be the point of working late?
During the week machines are left up to push automatic updates (5 minutes of downtime, times 10k employees, is about $80,000 of billable time). At weekends they get shut off either manually or under remote control.
Beep beep.
It's probably smarter to track IP addresses unless you control all the switches :)
Common wisdom (which may or may not be actual wisdom) suggests that powering up/down of computer power supplies is one of the largest sources of "wear" on computers nowadays, and so it's best to avoid that (replacing system components and increased costs in the industries to make this possible should be factored into eco-costs as well). Having systems go to sleep to various degrees presumably gets one much of the way towards being more eco-friendly without so much of this wear. That said, presumably a rigourous analysis on the topic would provide more reliable guidance.
For every problem, there is at least one solution that is simple, neat, and wrong.
A lot of places require machines to be on overnight because that is when automated update, monitoring and scanning tasks can run without impacting users. Of course, the machine could be configured to automatically shut down when this is finished. Actually shutting down is typically highly inconvenient since the machine loses state due to 30 years of bad OS design when this happens but a suspend-to-disk mode is a viable alternative.
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I would go with a reward plan. You could do something like give the top three most energy efficient people a gift certificate to the campus eatery (or whatever really). Calculate how much money is saved (out of everyone participating) and use part of that money to create a pool for the prizes. (It seems like for a large enough group of people, the energy and maintenance costs would reduce considerably, but I wouldn't really know ;)
I know I would definitely turn off my work PC every night if I got a free lunch!
It's time that all large campuses configured their systems hibernate automatically, if left unused for 30 minutes.
Really, there is no reason NOT to use the power management settings built into the OS.
I'm at a university and many of my colleagues leave their machines on overnight because they sometimes need access to their machine, either to retrieve a file or to run a program. If the IT folks provided everyone with a wake-on-lan script then everyone could turn off their machine. For years this has seemed to me like a no-brainer.
Is there some security or other downside I'm not aware of? Is WOL not reliable?
We don't completety power down any of our desktop machines. Users log off in the evening, and machines go to standby/hibernate after enough time has elapsed. Thus, users do not have to wait in the morning till the machine boots.
Machines are woken from sleep to deploy updates, etc. Many of our desktops are able to accumulate 30 days of uptime before the next patchday.
Energy consumption is a non-issue. We don't pay much for electricity.
The rest of the infrastructure - printers, faxes, access points, etc. runs 24/7. Again, the complexity to shut them down would never be equal to the energy savings.
I did this a while back, the trick is some machines are 24/7 others are 9-5 ers. I coordinated with dept heads to identify what entire departments could be shut down then scripted a prompt to fire at 7:00pm to look for any user feedback, working late crowd, then 30 minutes later do a shutdown if no response was received. This took care of most machines. I never got to the mixed departments, greener pastures called.
Shutting down at the end of the day and powering up the next morning increases the probability of HDD failure. It's better for the HDD to run all the time than to cold boot every morning.
I work for a large blue chip company and we have a strict policy of powering down at night (including monitor). We regularly audit the records to ensure the machine is powered down and users who are not are requested to always remember. A few users take a few reminders in order to do so and I have heard every excuse under for why they left it on and while some are valid the majority (95%) are not. Our reasons for pushing this policy is purely to save money and reduce unnecessary running time of the equipment. However we are in a position where only laptops users have VPN access so if they need to login to the network from home they already have their laptop with them. If we had open VPN access to desktop users I am sure we would see a lot of users leaving their computer on so that they can RDP into it over VPN.
It took about 6 months before we were at a realistic level. We have 633 desktops on our site so there is normally always a valid reason for one or two to be left on (valid reasons being batch copy, verify or processing of files). For those interested we have had a reduction in the amount of equipment failure (HDD mainly) as well as pretty good cost savings for power. Not to mention running greener (which regardless of if you believe in global warming or not is good).
I tend to leave the computer on overnight, but with things like monitor power-down and CPU idling enabled. When it's not doing anything it drops about 90% of it's power consumption after 15 minutes, and even when working with the monitor off (eg. running the nightly backup) it's still running at less than 50% of full power. If I power it off, by comparison, it can't run it's virus scan, backup, update check and the like overnight and has to do those things while I'm trying to use it during the day. Plus there's wear and tear to consider, I've noticed that the office computers that get turned off and on every day tend to fail and need replacing several times before mine (that stays on all the time) has a failure.
So my preference is to leave computers running but with power-saving features set to minimize power without shutting things down. This means hard drives continue to spin but the CPU goes into low-power idle mode. The monitor goes to suspend mode (beam and deflection power is off but the circuits and coils are kept warm), not powered-down completely. That seems to be the best balance between reducing power consumption, allowing it to run maintenance operations overnight and minimizing wear and tear and thermal stress on the components. If management absolutely insists on ignoring those last two in favor of the first, wake-on-LAN is essential to allow nightly maintenance to happen.
... but now IT has loaded so much crap on it ("desktop agents" [ie apps that spy on me], antivirus, patches, etc) that it is fully 15-20 minutes after turning it on before it is usable. So now I never turn it off. I did the hibernation thing for awhile, but then it stopped working for some reason and I haven't been able to fix it. And if I ask IT to fix it, their solution is always the same for every problem - wipe the machine - a tad inconvenient for me, but pretty efficient for them I suppose. Sigh.
The more you regulate a company, the worse its products become.
Among other projects, I worked on the power supply controls for the Cray Super Dragon. No, you probably never heard of it, but it became the Sun ES-10K.
This box had variable voltage power supples which required me to adjust them from cold start. I had to calibrate A/D, take samples, tweak, etc all through JTAG and cumulatively it was quite slow. Like over an hour.
My manager was not impressed, I shrugged and said "who turns these off?" - and the marketing droid/product manager said "they do in Japan". Fine. The hardware people were nice enough to give me multiple JTAG lines and power up time shrank to acceptable limits.
I have never been certain if this was a "Spinal Tap" riff or it was really true.
You might be able to set up an "exception" ticket with the IT department, or set up a Magic Packet arrangement tied to their machine.
Don't tell me to get a life. I'm a gamer; I have LOTS of lives!
I worked for a very large (top-3) pharmaceutical for years. They always asked employees to shut off their computers at night when they went home.
Then one day, they sent out a campus-wide email telling people to leave their computers on all night and over the weekend. They used the CPU cycles to run high-performance scientific computing jobs, saving the cost of buying a supercomputer.
Of course, not every company has a need for spare CPU cycles. This place did a lot of protein-shape searches etc..
In the comments and original message there are the following: -- Aside from the current fad of 'being green' -- -- I won't go into the green topic. -- -- nor any desire to "go green" -- In general this "community" is a group of technically minded people who are not opposed to putting science ahead of PR and marketing. Why on earth would such a group be so afraid of something because it is green. We all have to share the planet and I'm guessing most of us are not becoming billionaires by destroying it, so why is it such a problem for so many of you.
The CS department at the college I went to used to turn off all the PCs at night but now has them set up to start doing scientific calculations during the times when the labs are closed. They use power during this time, but it's not wasted.
I leave my computer on for a couple reasons. One is that if I'm in the middle of doing something and its time to call it a day, its easier to resume that if I leave everything as is. The second is that I may get paged to fix something and would need to remotely log into my computer from home, which requires it to be on.
I suppose if you could find a way to remotely hibernate a computer and remotely unhibernate it then you could potentially save on the electric bill.
Someone might be using it ... there are always a few late users. Trying to determine if a computer is in use in order to shut it down isn't always that simple.
... it won't be a 100% solution, but most people would probably comply, so for the comparatively little effort put in I bet you can hardly get a better return.
I suggest a simpler, low-tech solution - just stick up visible signs in the labs, and on some of the major office floors, asking people to shut down the computers in the evenings
Just the energy savings on that many computers would be not insignificant.
Microsoft seems to have figured it out. They shut down my computer for me quite often to do updates.
Anthropic principle: We see the universe the way it is because if it were different we would not be here to see it.
Do security concerns and power consumption issues matter enough to do this?
Yes and no.
When I first got comfortable in my current job, I made a big push toward "greening" our IT resources. As one obvious (erroneously, as I'll explain in a sec) step in this, I convinced most of my users to shut down at night. If we need to push out updates, WOL works just fine for turning machines on a couple hours before the start of the day, and it doesn't impact anyone during working hours.
Then I learned how electric billing actually works for commercial users - Put simply, your company doesn't care if machines stay on all night, because they pay based on their peak load, which will always occur during normal business hours. I had applied ideas that make perfect sense at home, to an environment where they don't apply.
Now, that doesn't mean we should just leave machines on 24/7 - Using electricity has an an environmental aspect in addition to the monetary cost. But if it inconveniences users by more than a few seconds every day, any conservation efforts will actually cost the company money in the long run.
So, I still encourage my users to shut down, and 95% comply. But if they consider it too much of a hassle, I can't financially justify forcing them to spend the first minute of the work day waiting for their machine to boot (not that anyone really works for the first five to ten minutes of the day, between coffee, hitting the bathroom, and just getting the obligatory morning socializing out of the way).
As for the security aspect of this, the servers must run 24/7, and any attacker would target them rather than some random user's desktop. I don't worry about an attacker using a compromised desktop as an intermediate step to the servers, because the desktops have no more privileges on them than anything else inside the firewall (and even then, not much more than a totally untrusted source, except for nonconfidential shared resources that we could restore in a matter of minutes if necessary).
One which is properly managed. It is a very bad thing when working nights and weekends is the thing to do. Except in a global situation where 2 in the morning at the work site might be noon where the worker is, or it the workers do most or all of their work at night. If it's just a matter of accessing some work files, that's what the fileserver is for, it makes far more sense to figure out how to set that up securely, than to hope that every one of a potentially huge number of computers is secure enough to access from offsite.
Encouraging people to pull all nighters or work on weekends smacks of an inefficient workforce or ineffective management. The only times people should be working those hours are because a job sprang up last minute due to an act of god or because the work requires that it be done when people aren't around. And in those cases if you've got on sight IT, it shouldn't be that difficult to set up an arrangement to cope with that. If you're going to have work done nights and weekends anyway, you may as well just outsource things to another timezone, and that's frequently a cost saving thing anyways.
Computers don't use a whole lot when they idle. Unless you are loading them up with lots of drives and a big GPU, you'll probably find they draw in the realm of 50 watts just idling. Ok so looking at my power bill I get about $0.06 per kilowatt hour of energy. At 50 watts of draw it takes 20 hours for a computer to use a kWh. Running the numbers I come up with about $100,000. So assuming the costs quoted by the grand parent are correct, one patch time would just about pay the power bill the whole year and two would go over it.
For better or worse, electricity isn't very expensive so it really isn't an area for huge cost savings. Also normal office computers really just don't draw much power when idle. They often don't draw that much even in operation. Enthusiasts get a little over excited with power supply sizes, but it's fairly rare to find the computer that actually needs a large PSU. You discover that even a system decked out with an 8800 and a bunch of harddrives would probably work just fine with a 400 watt PSU.
The good news is that Intel is working on something that may be a solution to this. Intel AMT should allow for systems to be remotely managed, including when they are powered off (computers don't go all the way off, they are still drawing a little bit). So you should be able to have them power up, do what they need to do, then power back down.
I can't help but laugh at those that quote reasons such as 'automatic updates' and 'antivirus scans' as legitimate reasons for leaving a computer on overnight.
With many enterprise management tools, such as Zenworks, it's quite simple to schedule a wake-on-lan task to wake computers up at say, 6am, to perform their daily tasks. It can even be configured to push out an automatic reimage of the machine. Once the updates and scans are done by 7am, people are just beginning to come into the office, yet you've still had a whole 10 hours of downtime. Incidentally, I've not seen a single computer in the past 4 years that doesn't support WoL on the mainboard NIC. Big bucks enterprise manglement apps aren't even required. A simple cron job, and some wakelan/ether-wake/wakeonlan/Net::Wake magic will do it for free. Just gather a list of Mac addresses with ettercap or your friendly ARP table or asset management app/spreadsheet.
May will say that the bandwidth requirements of updates squeezed into the 6am to 7am slot will degrade systems, but that's where a background process such as BITS should be used (as demonstrated by Eve Online, Zenworks, Microsoft and Google). The virus updates are a minor bandwidth requirement if you have suitable leaf services, and the actual scan is only locally intensive.
Being a public sector organisation, we're working towards a greener profile (due to govt policies), and all the tools are there and working. It just needs some effort on the part of the administrators.
You could also use that magic packet, to signal the computer to wake when the user swipes their access card first thing in the morning. By the time they reach their desk, their pc would be up and running. Ok, you have to link the access systems to a control server, but it wouldn't take too much hacking. They probably log accesses on a server anyway, so use that one.
BITD when I was an IT support type in a Cambridge University college, the library of that college had a small computer room with around half-a-dozen Macs (this was in the OS 8.x days.) These machines seemed particularly flaky, often requiring PRAM resets, restores and the occasional rebuild. It was only after a while that I learned why these machines were so flaky.
Every power outlet in that room was connected to a kill switch on the wall and come 5pm, when the room closed, yep you guessed it - someone hit the kill switch. Irrespective of whether students were using the machines and irrespective of which particular part of the write cycle the HD head was at.
The correct plural of virus is viruses.
occultae nullus est respectus musicae - originally a Greek proverb
No, a properly managed company would allow users to work when they want to the greatest extent possible. Don't assume that everyone prefers the same hours you do.
And for most positions, there's no need to make each physical box remotely accessible to allow people to work whenever and wherever they like, just a remote home directory for each user.
Back on topic, I think users can be given some input; the key is to make them think about the issue. Run a script that asks each user when his or her PC should shut off for the night. Then, if the PC has been idle for less than 5 minutes at that shutoff time, wait another half hour. This way, the guy who is most productive working from 2 p.m. until midnight can still save energy by having his computer turn off at 2 a.m.
Cant be as bad as Rite Aid, they require the management at the store to leave the computers, terminals AND EVERY light on even when the store is closed and empty.
They say its to help deter someone from breaking into the store and trying to steal stuff.....which im sure if you did the numbers would actually cost the company more to leave everything on, than to have a theft every once in a while....
Do lights really stop break-ins?
"an eye for an eye only makes the whole world blind"
Why not just have the machine shut down automatically on logout if it's between two specified times (eg. 9pm and 8am)?
Nobody else has this sig.
Unfortunately the EPA's EZ GPO page seems to have gone poof or something recently, but you can get it here.
Basically, you push a (simple) msi to the machines (I do this a lot of the time via psexec (props to Mark Russinovich) but there are other methods. Once you have that running on the machine you can configure how you want your machines to behave/re power management:
We also have a script that runs at midnight a few days of the month that does the magic packet thing as has been mentioned so WSUS and/or SMS (or SC:CM) can do their thing and automatic updates run as normal. In a few "why does my machine have to boot up every day this sucks" user groups we have a scheduled job to send magic packets about 15 minutes before they arrive to wake up their machines. With hybernate they hardly know anything happened.
Also I don't think signs will have anywhere near the impact you imagine. We can't even get users to not eat around the machines.
Obligatory disclaimer: This is my opinion, and may not reflect that of my employers. If you have a problem with it, take it up with me, not them.
I work for Dell. I can tell you for a fact that we take the environment seriously. The building I work in houses a 24/7 call center, but certain areas of the building are not 24/7. Corporate sales for the country are here, and take up half of the 3rd floor, for example. I happen to be in the sales department myself, and there's a piece of software installed on every desktop that hibernates the computer at 20:30 EST (with a half-hour countdown to that point). My department shuts down at 19:00, no other sales department is open past 20:00. We all open at 08:00 the next day, and the automatic hibernation sets an alarm to wake up the computer at 07:45. Alternately, if you turn your own system off through the start button and shut down, it'll stay off until you turn it back on.
We've also got computer recycling programs in place, and the "plant a tree" initiative where you can have us plant a tree for every computer you buy.
Sure. Some companies don't take going green seriously. But some do. And the number of companies that are taking it seriously is growing. Besides which, every little bit helps. Do you know the amount of energy that could be saved if everybody unplugged those electronic devices that "sleep" when they're not being used? 2W doesn't sound like much, until you multiply it by half a billion devices.
If you believe everything you read, you'd better not read. - Japanese proverb
At the school I work at, we have an automatic shutdown at 6 PM. It has a five minute timer and is preceeded by a text file in a DOS window reminding people that there is an "ABORT SHUTDOWN" option in their start menu if they are using the PC and the shutdown process begins.
/DELETE ALL (or whatever the syntax is) - to prevent the AT table from getting crowded with dozens of the same command
Two simple batch files for XP, on in the All Users startup directory, one in the All Users\Information Services directory of the start menu.
Startup:
AT
AT 18:00 "shutdown -t 600"
Abort:
Shutdown -a
We reset the AT table every day just in case some know-it-all high school student finds out such a thing exists and starts screwing with it. For the most part, though, not even the techs knew such a thing existed until I proposed using it.
We tried a lot of other ideas, but this is the simplest and most user-friendly. Big signs don't work, teachers and lab aids are no better than the students about following directions. Since implementing it 18 months ago, we've gone from having roughly 900 PCs online at night to about 100...including servers, timeclock systems running thinstation terminal sessions, and technology and admin workstations that are excepted from the shutdown policy.
120 characters for a sig? That's bloody useless.
Why not set the PC's to power off automagically? You could save yourself a lot of hassles...
Seven Days with Ubuntu Unity
Seriously. You need to take a couple of simple electrical courses. Specifically, volts-for-dolts a physics course on magnetism, and a practical, hands-on course working with electric motors. All handily part of an electrical engineering degree. When there is load on an electric generator, it takes more energy to keep it moving. Of course, we need to keep it moving at the same speed (60Hz or 50Hz, depending on which part of the world you're in) at all times, so that means using more coal, gas, whatever, when there is higher demand, and nearly none when there is no demand (not that that ever happens, but I will admit to the fact that you never use no energy even when no energy is being demanded).
In fact, my alma mater pointed out that they had a huge electric motor (approx 20' tall) that did nothing but spin (not doing any actual "work") to lower power demand for the university. When the capacitance of the grid got too high (such that voltage and current were too far out of phase with one another), they'd turn on the motor (basically, an oversized inductor) to correct the phase, lowering the demand on the external grid, resulting in a real cost savings to the university on their huge electrical bills.
The CO2 output of your carbon-based generators will be drastically lower at night than during the day. It's really that simple. I'm no greenie, but this is simple fact, and completely non-controversial. Just go ask your local power utility.
I know in particle physics we need to leave our computers on overnight quite regularly. We share computing resources and often run simulations for several days (or longer). Shutting down the routers and switches connecting one computer to the rest of the particle computers in the building effectively cancels the simulation since huge datasets might be spread across 7 or 8 computers. At CERN, when the LHC turns on there will be thousands of computers running 24 hours a day for many years. At a university, obtaining your sample set of data may require at least a day (you're expected to pull the data and then work with it rather than using CERN computing resources, although the specifics haven't been worked out yet). Some projects just require that much time and energy. Most days you should be able to shut off large portions of the network, though.
I'm certain there are other sciences that have similar concerns. I think the best way is to send out a friendly e-mail reminding people to turn off their computers when they leave. That should get at least a handful of computers off for the night. Depending on how successful or unsuccessful that strategy is, shutting off computers that are definitely unnecessary (public access terminals for example) would be a fine idea.
Too bad for them. People leave themselves logged in all the time at the end of the day. Too many people are sloppy for us to make allowances for things like that.
It should be noted that this is a public K-12 school, not a university. There aren't many people around at 6:00 outside of administration personnel. Those who are have been warned what will happen; if they get up at 5:58 to do whatever and come back seven minutes later to their PC shut down, they'd better have saved their work.
120 characters for a sig? That's bloody useless.
IIRC, the "shutdown" command DOES adhere to whatever secutity settings have been laid down in the Local Security Policy (or Group Policies for the larger organisations out there). One of the settings for the local machine that is amongst the configurables here is who can shut the machine down locally, and who can shut it down remotely. The two lists are separate and by default EVERYONE can shut down the machine if logged in locally, but to shut down a machine across the network you'd either need to be explicitly added to the ACL or would need to be in the Domain Admins group (where the machine is a member of a domain).
Just my $0.03 (At current exchange rates, my £0.02 is worth more than your $0.02)
They really should get their own computer instead of sneaking into a public school. Do you have any idea what kind of trouble that can get you into these days?
120 characters for a sig? That's bloody useless.
I work for a medium size European bank. Total workstations aprx. 22000 in 13 different countries.
We used to leave all our PCs on all the time in order to run updates, patches etc.
In my area of operations there are only about 3300 PCs. Nine months ago we implemented a policy where all users were required to turn off their PCs (not servers) at the end of day. Wake-on-LAN was used to turn the PCs on during the night for updates and 15 minutes before the start of the workday.
Very conservatively, we estimate that we will save about EUR153000 (USD225000) every year (I live in a country with very high electricity rates).
So, it is definitely worth it financially, our users were not adversely affected at all and it helped morale by making the workplace a greener place.
so, driving uphill uses the same amount of gasoline that driving downhill?
the power station does throttle down at night. they keep the generator at the same speed (3600RPM I guess, to give you 60Hz). but they don't need the same amount of fuel to keep it going. the usage on the grid acts like a brake on the generator, in the same way that the road conditions affect your bicycle.
if it's steam-based (gas, coal, nuclear), you need more steam to keep a higher pressure, to keep the generator rotating at the same speed, and that means heating more water, and more water needs more energy, and more energy needs more fuel. hydroelectric plants shut down unused turbines.
It's amazing how people can have such strong feelings about an issue and have them be based on such utter nonsense.
Have you ever jump-started a car? Did you not notice how when you connect jumper cables to the vehicle with the dead battery, the running car has its engine get slogged down by the extra load? And does it not stand to reason that if you want to hold the engine at the same RPM (as an electric utility has to do to hold line frequency) you have to feed the engine more gas to do so?
If you draw more power out of a circuit, somewhere, more power has to be put in.
Peak load is why extra power plants need to be built. Sure, it is great to decrease that to prevent the extra emissions. But the loads at all times of the day and night should be reduced as well where possible.
In a corporate environment, that sort of decision is made at a corporate policy level, and not at an IT personnel level. Nobody would get fired.
When our name is on the back of your car, we're behind you all the way!
You're focussed on yourself, I bet if you went out and asked the users you'd get a lot of replies around "yeah, the stupid thing tries to shut itself off just when you don't want it to".
Live by your own rules.
In the company I currently work for, every PC is powered down at night, with only a few exceptions. There are obviously servers still running, but they are actually doing something (backups for instance), and there's sometimes a few machines involved in over-night test procedures. Frankly there is no valid reason for keeping a PC running if it isn't being used. Same goes for the home PC, btw. Switch it off at night.
If a train station is a place where a train stops, what's a workstation?
My computer (a laptop) is on 24/7 and I would never want to be bothered with waiting for it to come back on. It takes about a minute, but I don't want to spend it. I do not pay the bill really either at home or at college, but my computer is never doing nothing. I always have torrents seeding and downloading, other downloads, things to encode, all kinds of things. Sometimes, I recompile big packages in Gentoo (definitely an overnight procedure). It's incredibly useful to have it on all the time.
The only times this computer goes off is for a few ms when it's rebooting to go into Windows or just rebooting (not very often). Often this computer is in either Windows or Linux for days before another reboot.
However, I do hate when computers are on and are not doing anything at all. My room mate would leave his laptop on all the time doing NOTHING other than being connected to AIM. I guess if he wants to receive messages while he's gone (a modern answering machine). But to me it's entirely useless. I hardly ever receive messages while away (yes I may not be equally social as my room mate, other than IRC all the time).
I guess if I had NOTHING to do with computers then I would not have mine on much, but I do A LOT.
If I were a taxpayer in your district, I would appreciate the savings on the school's electric bill.
== First cross river, then insult alligator.
Our AD policy (since most computers are Windows) forces a powerdown at 7pm (our offices all close at 4:45pm, except for a few.) The user can abort the shutdown by clicking on a button, or can simply reboot. AD policy also exempts the systems we know shouldn't be shutdown (24 hour serivce points.) At this point, we estimate we save about $30,000USD per year in power costs for the 1/3 that have this impliments. (It's a big network.)
Interestingly, our network guys are having trouble routing wake on lan packets accross subnets, so we are looking at a T104 form factor linux appliences with multiple nics to send out WOL commands. Not sure this isn't a brain fart on the part of the network guys, or simply a limitation on how WOL works. Since we have other reasons for wanting a boxen on each network, it's a good excuse.
Necessity is the plea for every infringement of human freedom. It is the argument of tyrants; it is the creed of slaves.
My Company has "white" power outlets and "pink" power outlets. Pink outlets provide power 24/7, the white ones all shut off (along with the office lights) when the building alarm is armed. All offices have at least one "pink" outlet so if you really want your PC to stay alive you connect to that one.
Everyone knows that most of the students sit up all night slashdotting, playing WoW, facebooking, digging. The night is the best time to have some "quality time" with you and your computer!
One is efficiency. Powersupplies, good ones at least, are quite reliably most efficient at half their rated power. So get a 600 watt power supply, it's efficiency peak will be at 300 watts. Hence it behoves you to buy a powersupply that's double what you need. While the difference generally isn't major (maybe 2-4% between half and full load) if you are spending the money on a quality, efficient supply anyhow, why not get one that runs at its most efficient point?
Another along those lines is if you want a good power supply, your options are sometimes limited. When I went to get mine I wanted a Corsair supply as I really like their design and build, but 520 and 620 were the only two wattage options. Works out ok, I have a very high power system and a 620 is about double what I need so peak efficiency, but regardless I had little choice if I wanted those kind of supplies.
The final reason is if you instead buy a cheap supply that they are rated improperly. First off they are often rated rather unrealistically. A 500 watt supply will only supply 500 watts if it is very cool, and 500 is the absolute max, the failure point (whereas a good one will supply 500 even at 50+ degrees C and can do so without risking failure). Also they often don't have enough power to given rails to meet you needs. So while they might be 500 watts total, there isn't enough amperage on the 12 volt rails for your system, because a large part of that wattage is for other rails (good ones generally have lots of amperage on all rails, often enough that you can't load all rails fully, but provided some are loaded light you can load other heavy).
Hence lots of people buy overspec'd powersupplies either because they've been screwed on cheap ones, because they want a particular good one that is only available in certain ratings, or both. I mostly just wanted to point out that doesn't mean systems draw that much, especially when idle. Many people see computers being put with 500-1000 watt power supplies and assume that means they draw that much power all the time. That's just not the case. You'll find that a system may have a 500 watt power supply but draw only 200 watts when fully loaded and only about 50 when just idling.
You are the sys admin are you not? Maintaining the operation of the network is YOUR responsibility. That includes maintaining it's carbon footprint.
Push out an update to disable screen savers, turn monitors off after 15 minutes of inactivity, and hibernate after 1.5 hours of inactivity (this saves them from having to boot up after lunch), and set Windows to require administrative privileges to change power management settings.
Piece of cake. If they run Linux s/Windows/Linux above.
You may find this interesting. I used to work at a nuclear power plant. The cooling reservoir was connected via a spillway to a nearby river. To cover peak loads, there was a hydroelectric plant on the spillway. At night, the power company I worked for bought tons of cheap electricity from another utility to run the hydro plant backwards to refill the reservoir.
The plant I worked at stayed running at 100% the whole time, but as far as I know, its power was not used to refill the reservoir. I assume that was because the utility that owned the plant could sell that station's power for more than it was paying the other utility for the power to refill the reservoir.
One of the engineers told me it took approximately twice as much power to refill the lake as was obtained by draining it, and this happened on a fairly nightly basis during the summer. I used to run a few miles at the plant every morning, and there were usually fishermen trying to get as close to lake side of the dam as possible without getting chased off by the guards. The churning water apparently stirred up a lot of stuff and attracted the hungry fish in the lake.
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