Slashdot is powered by your submissions, so send in your scoop


Forgot your password?
Linux Business

Use Linux to Reduce Your Power Bill 209

Stephen Herzog writes "Linux Devices has published an article about the AcquiSuite, a Linux based hardware device that collects and reports energy consumption information. Companies who are looking at energy management solutions need to keep the cost down in order to recover their retrofit cost with savings from the energy bill. Linux is a perfect fit for cheap data collection devices in part because "Linux provides complete TCP/IP functionality, PPP... and no royalties"."
This discussion has been archived. No new comments can be posted.

Use Linux to Reduce Your Power Bill

Comments Filter:
  • FUD! (Score:5, Funny)

    by NanoGator ( 522640 ) on Wednesday October 16, 2002 @04:14PM (#4464120) Homepage Journal
    Everybody knows that Windows machines use less power than Linux because they're not running as much.

    There, I made the obligatory Slashdot 'Windows is unstable' joke. This should render the rest of the stale jokes -1, Redundant.
    • Reboots tend to be big energy drains.

      And for those times that the Windows box is running, there are large energy draws from the mechanisms in place that
      a) ensure you do nothing to violate any copyrights of anyone anywhere ever
      b) contact your employers, friends and family should you start expressing interest in any form of open-source solutions
      c) track your every move and thought for future marketing purposes.

      • I thought you wrote "*robots* tend to be big energy drains."

        Robots that ensure you do nothing to violate copyrights, that contact your employers, and that track every move you make.

        And remember: RIAA representitives that deny the existence of robots may be robots themselves.
    • It's true. (Score:5, Funny)

      by bill_mcgonigle ( 4333 ) on Wednesday October 16, 2002 @04:26PM (#4464221) Homepage Journal
      We had an improperly-vented Athlon machine running Windows that was fine (as much as could be expected). We installed RedHat 7.2 on it and redeployed it as a server, and the CPU melted. Apparently, Windows was under-utilizing the CPU.
      • by Anonymous Coward on Wednesday October 16, 2002 @04:41PM (#4464326)
        We had an improperly-vented Athlon machine running Windows that was fine (as much as could be expected). We installed RedHat 7.2 on it and redeployed it as a server, and the CPU melted. Apparently, Windows was under-utilizing the CPU.

        I've heard a lot of dodgy arguments for switching to Linux, but this one takes the cake.

        "Linux is so much better than windows that when I installed it, it fried my machine! This is concrete proof that Microsoft cannot write an OS"
        • ""Linux is so much better than windows that when I installed it, it fried my machine! This is concrete proof that Microsoft cannot write an OS""

          Actually I think he was saying "Windows is more efficient than Linux because it's getting stuff done so fast that the CPU is underutilized."

          Heh. At least I got a laugh out of it. :)
  • Did this in College (Score:5, Interesting)

    by Anonymous Coward on Wednesday October 16, 2002 @04:15PM (#4464121)
    We used proprietary software that cost a WHOLE lot and sold it to people for a lot. But it still saved money. Now the outfit is having to switch over to more Linux/OSS based stuff because they're running out of funding.

    Except for the government clients.. they alwasy seemed to have money.
  • by gpinzone ( 531794 ) on Wednesday October 16, 2002 @04:15PM (#4464129) Homepage Journal
    ...can it also play OGG files? Hey how about doubling it as a firewall? Come on! Where's your hacker spirit?!
  • by Drunken Coward ( 574991 ) on Wednesday October 16, 2002 @04:15PM (#4464130)
    With the stability of Linux, I can leave my boxes on for an almost infinite length of time. So I do :). I never could do that with Windows, the machine would get all borked after only a couple of days. I guess Linux increases my power bill.
  • by Anonymous Coward on Wednesday October 16, 2002 @04:15PM (#4464132)
    Use Linux to Reduce Your Power Bill

    You won't bathe, so there will be no need to waste power on hot water.
  • Just Linux? (Score:4, Funny)

    by grub ( 11606 ) <> on Wednesday October 16, 2002 @04:16PM (#4464140) Homepage Journal

    I save *loads* of electricity when I do a "shutdown now" on OpenBSD!
  • by MacOS_Rules ( 170853 ) on Wednesday October 16, 2002 @04:17PM (#4464146) Homepage
    I'm reading the article and thinking "Wouldn't it be more effective to just turn the damn thing off?"

    -Yes, this IS a joke. :)
  • by Anonymous Coward
    ...because Linux doesn't support ACPI.
  • by PhysicsScholar ( 617526 ) on Wednesday October 16, 2002 @04:17PM (#4464152) Homepage Journal
    Out of the various possible routes taken by an electron in orbit, one line l may be chosen with peak in point p relative to which the line is symmetric (relative distance and velocity, v(p), are minimal).

    Therefore, the scalar potential field created by such movement obeys Zipf's Law of Power (so do Web links, but that's another post).

    Bottom line -- be weary of news releases such as this one that proclaim to reduce energy use and save you money. Unlike the X10 cam, most of these crocks of crud simply don't work!

    Also, here in the UK our AC currents are very different from traditional outlets you folks may have in the States. Yet another question to ponder...
  • by Anonymous Coward on Wednesday October 16, 2002 @04:18PM (#4464157)
    "Use Linux to Reduce Your Chances of Contracting Sexually Transmitted Diseases"

    That's right, act now and no female will want to get within 100 feet of you!

    Christ, any other trivial fucking benefits we can wow potential users with?
  • by El_Smack ( 267329 ) on Wednesday October 16, 2002 @04:18PM (#4464158)

    Use Linux to Reduce Bill(s) Power.
  • by Mustang Matt ( 133426 ) on Wednesday October 16, 2002 @04:20PM (#4464170)
    kill a watt [] meter does this too.
    • by pjrc ( 134994 ) <> on Wednesday October 16, 2002 @05:43PM (#4464784) Homepage Journal
      I hope this post can explain a bit about what the AcquiSuite is all about.

      I know Steve and the guys behind the AcquiSuite. I designed the Veris Enercept power meter that's shown on their home page. In fact, I can probably take credit for convincing them to go with Linux on x86 a few years ago (they were also seriously considering PSOS on the netsilicon ARM+ethernet hardware). I didn't actually participate in the AcquiSuite though, and I'm not affiliated with them, and I recently left Veris Industries. So take the rest of this comment with a grain of salt... I'm not totally impartial, but I do know quite a bit about the system.

      The AcquiSuite is designed for use in commercial buildings and groups of buildings. It can monitor many power lines, not just one socket. The Veris Enercept meters are typically installed in the breaker boxes that feed major sections or subsystems of a building. These meters are meant for 3-phase power systems in the 20 to 2400 amp range, not single-phase 120 volt, 15 amp residential. The AcquiSuite also interfaces to temperature, humidity and other types of sensors.

      There's three major factors (as I understand):

      1. Data is logged, so you can see when the power was used
      2. It's cost effective to collect the data, as many AcquiSuites can call to a single PPP dial-up account and transmit their data to a server
      3. They've done a lot of work to make it inexpensive to install the AcquiSuite and its related sensors

      One of the key factors is cost... since this thing is supposed to save energy, it needs to be a lot less expensive that what it costs to install.

      Compare to the "Kill A Watt" (which actually offers similar functionality for single-phase 120 volt as the Veris Enercept, but on a LCD instead of RS-485 network). With a simple meter like that, you can look over at it and see the power company is give the correct voltage, and how much current/power you're using at any particular time. You can see the accumulated consumption, so you could jot that number down every month and see how much the attached load cost you.

      But to be useful in truely saving money, you need to log the data, collect that data, and get an analysis of that data in a timely manner.

      You can go to your conventional power meter, be it the "Kill A Watt", Veris Enercpt, or the "glass meter" on the side of your house and read what it says. If you remember what it was last time to read it, say a week ago, you might say "damn, I used a lot of power this week, I'll have to try to do better next week... but how?"

      Now enter the AcquiSuite (or other data logging methods): when you're wondering about your power usage, you visit a website using your browser, and in seconds you have a detailed plot showing how much power you were using throughout the day. It's similar to those bandwitch graphs from MRTG, you see a massive anamoly and say "holy sh*t, what happened the night before last that used so much power"? Or perhaps you see the longer time scale and see that something hogs lots of power every Monday morning. Or perahsp you compare graphs for similar office spaces in different buildings and see that one office uses a lot more power than the others, and perhaps only in the morning.

      This is the sort of information that you really need to find where power is being wasted. And it's the timely fashion that's required to actually do something about it. You can find the janitor who didn't turn the light off, or modify a factory start-up proceedure for sequencing those machines properly on Monday morning, or fix the heating system in that one office that's using too much power.

      That is what the AcquiSuite, and systems like it, are all about. They log data on a fine enough time scale from enough locations that you can (hopefully) see those unexpected events that are wasting power and costing money, and you can see them very shortly after they occur, so you can actually go do something about them.

      One of the neat things about the AcquiSuite is it's ability to use the internet (linux tcp/ip stack and ppp). It can call an ISP and upload its data to a server, and as I recall it can be set to do this on a schedule with many others, so that a whole bunch of them can share just one dial-up account to send their data. I was told that a lot of people install them on their existing fax line, since it only makes calls infreqeuently and off of business hours. There were a bunch of other simple but nice features to the AcquiSuite that Steve was telling me about, but they escape me right now. Oh well.

      I hope this has cleared up some of what this is all about. I know a lot of slashdotters see a product and only think of its application in a resedential application, mainly their house, appartment, dorm room, etc. This thing is targeted at commercial builds and groups of buildings.

      • I wish that every single outlet in my home had a kill a watt type meter being logged.

        What do you recommend for the home user that wants something like this just for the nerd factor and doesn't have a million bucks to spend?

        I suppose we could rip open the kill a watt and try to create an interface for it so we could log it's data but still that's not very practical.
        • What do you recommend for the home user that wants something like this just for the nerd factor and doesn't have a million bucks to spend?

          There just aren't many products targeted at residential applications, because the money spent on power (withint one hoursehold) and the opportunity for reducing it just isn't enough to justify buying equipment.

          I suppose we could rip open the kill a watt and try to create an interface for it so we could log it's data but still that's not very practical.

          Ask me this question again in 15 months, when my non-compete agreement with Veris is expired. Normally I don't worry too much about that, but this is a power meter, and I spent years at Veris designing power meters.

  • by UnidentifiedCoward ( 606296 ) on Wednesday October 16, 2002 @04:20PM (#4464174)
    to monitor water usage. It is actually kind of cool from my geek perspective. You get a bill for utilities from a company in Texas which is where the data is aggregated.

    At first when I saw the box and I didn't know what it was so I called the phone number and asked what it was and they said oh it is an embedded machine to remotely monitor your water usage. I guess I got a tech/service operator because they were very knowledgable and said it uses embedded linux and want on to explain how it works (in general terms). The rep said the only presence they have in Seattle is for a technician for service related calls.

    You could easily imagine running a utility company on a skeleton crew with only a strong capital investment on the onset. Makes you think.
  • HVAC. (Score:3, Interesting)

    by garcia ( 6573 ) on Wednesday October 16, 2002 @04:21PM (#4464188)
    my father is a HVAC mechanic. He currently works as the Maintenance Supervisor at an animal testing facility in NEPA.

    He says that such devices are practically non-sense. Changing CERTAIN devices related to HVAC will save you $200 to $500 over a 10-15 year period. There is NO way to save much more in large buildings (which this device seems to).

    You are going to have to pay for new equipment to save then you are going to have to watch the savings over the years after the equipment is changed.

    it's really not as great of a device as they say it is.

    It's pretty much on the front page b/c of free advertising at least IMHO.
    • Re:HVAC. (Score:5, Informative)

      by DaCool42 ( 525559 ) on Wednesday October 16, 2002 @04:29PM (#4464247) Homepage
      Your father doesn't know what he's talking about. Power quality is a MAJOR issue. Any place with large amounts of inductive loads (ie fluorescent lights, motors, etc) can easily triple their electrical bill by not having a good power factor. It is standard practice for electrical companies to charge extra if your power factor is bad as well. What he may be referring to is heaters. A heater is not an inductive load, so it will already have a power factor close to unity. However, in a large building with lots of motors/fans/air conditioning, power factor is a very important consideration. And if you get into an industrial setting, you would have to be completely insane not to care about power quality.
      • Re:HVAC. (Score:3, Interesting)

        by garcia ( 6573 )
        Yeah, he replaced MANY parts of the HVAC equipment in the facility he currently works at.

        First of all, he had to determine the amount of power that the current units were consuming. Then he had to figure out what the new units would consume. After that he had to present this material to the reviewers.

        Now. Let's say he gets paid $X/yr. The people under him get paid $Y/yr. They are going to have to replace Z amount of fans at such and such a price.

        Now. How many hours these changes will have to take coupled w/the cost of the changes, is going to save HOW much?

        When you become a certified HVAC mechanic w/30+ years of experience, you can come talk, until then, please express your views to someone else.
        • When you become a certified HVAC mechanic w/30+ years of experience, you can come talk, until then, please express your views to someone else.

          (And for those who missed it... )

          my father is a HVAC mechanic...

          Bill, it doesn't matter if your father is a billionare who invented indoor electricity. Unless HE signs in with his own UID and posts, it's just heresay.

          I wager that your father didn't read the article, and that you're not a certified HVAC mechanic, either. Aruging from authority's a despicable practice, especially when it's not YOUR authority.

          Eventually, everything gets replaced. When doing so, it's important to look into the savings of more expensive "smart" components as opposed to the traditional ones; the cost differnece doesn't have to factor in time to replace if that's going to happen anyway.
      • Re:HVAC. (Score:2, Informative)

        by tuuw ( 598112 )
        Ummm, electrical devices with a poor power factor do NOT consume more power, ie they wont
        increase your power bill. What they will do is increase the line current to the device.
        But since this increased line current is out of phase with the voltage on the line no additional real power is used.
        Industry and electrical suppliers tend to be concerned with power factor because increased line current means you need larger conductors to supply the load which means higher cabling costs.

        Trust me, I'm an electrician
    • Some perspective... (Score:5, Informative)

      by gtwreck ( 74885 ) on Wednesday October 16, 2002 @05:26PM (#4464663)
      I work for a building automation systems manufacturer and have designed, built, and sold energy management/building automation systems since 1987. Your father is operating from the perspective of an HVAC mechanic and has a particularly narrow perspective on energy management in general. Yes, replacing inefficient equipment can reduce costs at apparently minimal levels. However, he likely has never worked with a BAS that was configured correctly and adequately supported by the vendor.

      A properly installed and configured building automation solution will find most of the savings are in finding ways to reduce demand through scheduling, staging, load sharing, load shedding, cycling, super-cooling, and other strategies. By reducing demand, you can go to a utility and negotiate reduced rates based on staying withing certain demand levels during peak times during the day.

      Simple things like making sure the lights, HVAC, and things like escalators come on at the right time in a staged order (to prevent demand spikes), and only where they are needed and are shut off when they are not in use (at night) can save a large facility literally millions every year.

      Changing out HVAC equipment for more efficient equipment is a very tiny part of the puzzle.

      BTW- all of the major BAS manufacturers (including my employer) have such a meter-monitoring unit, and many of them or related systems are increasingly based on embedded Linux. Meter monitoring units are useful to monitor a facility before it is put under complete control to determine where the savings can be found. Once the facility is in place, meter monitoring and associated daily reports are typically used to ensure that the system is operating properly, but in this case there is much more information available.

      So to say you might only get a $200 to $500 payoff over 15 years is small potatoes compared to the potential millions you can save at a typical big-box retail, manufacturing facility, or large high school.

    • Re:HVAC. (Score:5, Interesting)

      by pjrc ( 134994 ) <> on Wednesday October 16, 2002 @06:19PM (#4465053) Homepage Journal
      Even if this is true, there's a lot of other loads in the building besides the HVAC system.

      I know a story of a company (which I can't mention due to former NDA) that used a system similar to this AcquiSuite. The guy who saw the facilities manager for a large "campus" hired a database consultant to build some scripts to automatically update a "naughty" and "nice" list of the departments who used the most and least power per square foot of their respective areas. He had it automatically send emails to the managers of any sections that wasted a lot of power relative to the other areas.

      Much of their power bill turned out to be for lighting, and by the managers simply telling their people to turn the lights off, their power bill went down considerably. The peer pressure of having the departments compared to each other went a long way towards motivating and sustaining measures to save power.

      So your dad may be right, or he may be wrong about HVAC, but there's a lot of ways to save power besides ripping out your furnace and cooling systems.

      Just to mention another one, I know of a place where they had a large peak demand charge (power companies charge for peak usage as well as comsumed kwh on the east coast), and it turned out large machines which melted material with heaters were all "warming up" at the same time. By having the machine operator come in to work an hour earlier and turn the machines on in a sequence they saved thousands on their monthly bill. I heard a similar story of a heat-based machine that caused a large peak because whoever installed the machine went "overkill" on the number of heating elements. They just cut the wires to half the heaters, and the machine took twice as long to warm up (was on a timer anyway in that case) but didn't set a record peak and thus the power bill went way down. In both those cases, they believed their excessive peak demand bills were from actual useful work, but once detailed data was logged it turned out to be from machine startups and they saved lots of money by simply starting the machines up differently.

      So you may not think it's such a great device, but there are a lot of people who've saved a lot of money simply by learning where they were really using power and making simple changes to the way they operated. They would probably not agree with you.

  • At our office... (Score:5, Informative)

    by qurob ( 543434 ) on Wednesday October 16, 2002 @04:26PM (#4464225) Homepage

    We call the power company, and they give us detailed reports on how much power each site is using, and day-by-day breakdowns, comparisons with last year...
  • Which chip though? (Score:4, Interesting)

    by toupsie ( 88295 ) on Wednesday October 16, 2002 @04:26PM (#4464226) Homepage
    If you want to reduce power usage, would you want to use an Intel x86 chip in that goal? Wouldn't a PPC Linux be more power efficient? I am sure others can bring up other lower power consuming chips that have Linux ports than Intel's power hungry beast.
    • You could use a PPC chip, but that would mean that you would have to buy a stove to do the cooking. Intel is ahead of the game having converged computing with the kitchen.
    • If you want to reduce power usage, would you want to use an Intel x86 chip in that goal? Wouldn't a PPC Linux be more power efficient?

      I doubt it, they are using a 16MHz 386 for this. That probably uses less than 400mW and runs cool to the touch without a heatsink. Something based on a MIPS/ARM/PPC core would provide a lot more MIPS/Watt though.

  • by Camel Pilot ( 78781 ) on Wednesday October 16, 2002 @04:27PM (#4464232) Homepage Journal
    Rearrange the words and now it makes sense.
  • by krray ( 605395 ) on Wednesday October 16, 2002 @04:27PM (#4464235)
    Using Linux itself has just saved me money in my time. "It just works". Make a change, reboot, make a change, reboot, reboot? Never. Mysterious crashes? Long gone.

    I've also always had I believe a CM11a plugged into one of the serial ports. It's called X10 and allows signalling to take place over the electrical lines.

    Linux takes care of outside lighting, HV/AC, and a host of other operations for me around the house. Add in a RF remote and all of a sudden you can control/dim the lights throughout the house with X10 and the remote in your hand (Linux does nothing here).

    Can Windows control the lights? Of course, but I've never seen a Windows box "just work" with no human intervention for years on end.

    I like the fact that when I walk into the bathroom at 2am (for obvious reasons :) that the lights turn on automatically (sensored to X10) and the Linux box sees this (and the time) and dims the lights automatically for me. HHmmm, this saves power too!
  • Nothing New (Score:5, Informative)

    by JesseL ( 107722 ) on Wednesday October 16, 2002 @04:30PM (#4464254) Homepage Journal

    I've already worked with two companies doing almost exactly the same thing.Check these out: [] []

    Both are embedded linux systems for building automation, power consumtion monitoring, and providing information about the monitored systems over the internet.

  • by Anonymous Coward
    With respect to persons saying that energy savings is not practical.

    We typically sell the AcquiSuite product to contractors who work on a performance based contract. The building owner pays some fixed amount for a retrofit which includes things like CF lamps, new motors, etc. The contractor only gets paid when the proposed reduction in electricity is verified. Typical contracts suggest 7-8% reductions in buildings with $20k anual electric bills. The AcquiSuite is used in these projects as a measure of before and after, and is used for ongoing maintainance.
  • by I_am_Rambi ( 536614 ) on Wednesday October 16, 2002 @04:36PM (#4464293) Homepage
    But linux is also proven to reduce your processor heat as well. Its called two little assembaly opcodes that Linux uses.


    This two little commands enable all interupts and then halt the processor (in that order). So while the box is doing nothing, the processor is also doing nothing, excepting waiting on some interupts to go back to work. Because the processor has halted and is doing absolutely nothing, it has time to cool down.

    Windows, as far as I know, does not implement these opcodes, and I don't know excatly how they could get away with it. I guess that is how processors burn up. Maybe these opcodes help in the deduction of your power billsince the processor is no longer "active".

    All opcodes are for the Z80, I do not know if they are the same for the x86 processors as well, but the theory is the same.
    • by SuiteSisterMary ( 123932 ) <slebrun&gmail,com> on Wednesday October 16, 2002 @04:44PM (#4464350) Journal

      Windows 9x doesn't. NT/2K/XP do.

      You can get apps for 9x, such as Rain, that will run as a lowest-priority thread and issue the HLT commands.

    • OK I'll bite...

      How did you get Linux running on a Z80? I think you might be pulling this stuff out of the air.
    • by MrEd ( 60684 ) <tonedog@ha i l m a i l . net> on Wednesday October 16, 2002 @05:16PM (#4464583)
      That's as may be, but my Linux box still uses more energy than my 2k because the boot disk won't ever spin down! I have hdparm set to powerdown both the drives after half an hour, but the root drive is being accessed every five minutes or so for various things.

      I realize that I could dig through my logs and find out why sound-slot-0 is being modprobed every so often even though my one ALSA-driven sound card is inserted at boot. Or I could find a way for my log files to be written to ramdisk (since I'm not running a server and have a UPS). Sure is a lot of work though! Aren't there laptop users that have gotten distros to hack together workarounds for this stuff?

      Last HOWTO I saw on this was about 20 pages long and looked mighty timeconsuming. Anyone have any tips on quick-ish ways to make Debian Sid disk-friendly?

      • I had noflushd installed on my laptop for a while. It not only spins the drives down (well, it tells hdparm to tell the drives...), it caches all filesystem writes. So, if your problem is things writing to the disk, noflushd will be of use to you.

        I stopped using it because I put XFS on the disk. Journaling filesystems tend to bypass some of the kernel disk-writing procedures in order to make sure the journal is correct. If you're using a journaling filesystem, that may be the cause of your problems. I'm not sure there's any way around this, because the filesystem seemed to write things about every five or so minutes regardless of whether I was actually reading or writing to the disk.

        --Phil (And now the laptop itself is dead. Sigh.)
    • If you run an intel processor, it systematically shuts down logic thats not in use (fpu, etc), and it has nothing to do with the OS. It will shut itself down, the equivalent of a halt, without the halt.

      Only the Athlons need the archaic halt command.

      Nice troll, though.
  • With the mention of modbus and all :), I guess this thread might be a good time to ask for links on cases where Linux has been put to industrial use. Is there something significant, I mean for example cases where Linux is crucial part of keeping a $100 million industrial machine running and producing somethoids. Anyone?
  • The only thing Linux needs to attract the wierdos! Lets go guys, what can we come up with?
  • Does anyone know of any inexpensive power meters that you can stick between an appliance and a wall socket that records power usage? My electric bill is insane nowadays, but it's really hard to track down exactly where the power is going. I've tried to find a cheap device like this ($50?) but have had no luck.

    The idea is not to have just a meter that take an instantaneous reading, but to have something that adds it up over a 24 hour period (or whatever).

    • by Anonymous Coward
      Electricity can escape unless you keep plugs in every outlet to keep the electrons from leaking out onto your floor.
    • Look at your power meter when things are running. Then turn some of them off. Shortly after I moved into a new house, I noticed my meter was going pretty fast. After turning things on and off, I realized that the 5 vanity lights above my bathroom mirror were using a boatload of electricity, more than any other thing in my house. Probably more than any three things running at once.
    • by JesseL ( 107722 ) on Wednesday October 16, 2002 @04:53PM (#4464427) Homepage Journal
      Radio Shack has one here []
    • Yea, $50 exactly:

      Kill A Watt []

    • First off, turn everything off, including any stoves, dishwashers, hot water heaters, A/C units, refrigerators, etc - in fact, what might be easiest (but make sure you have surge protectors for computers and electronics) is to simply turn off the breakers. The disk (if your meter has it) should be not be turning at all - if it is, then you have a parasite load attached (alarm system backup power or doorbell most likely), but it should only turn really slow with those. If it is turning faster, then someone is either tapping your power in some manner (for whatever reason), or you have some kind of short in the system somewhere (of course, if you have all the breakers off, and it is still turning, you have big problems) - which is a bad thing (don't laugh - it is possible to have a high-resistance short in a line that goes for years without any noticing, other than a high electric bill - my brother-in-law's parent's house recently had a fire due to a drywall nail that had been driven through the wires of one of the circuits - it had been that way for YEARS before the fire happened).

      Anyhow, that is one way to find out what circuit or appliance is sucking the power. Another way is deduction - the biggest power users in a house are typically the hot water heater, the refrigerator/freezer, and the air conditioning unit (which means AC/heater if equipped). Not much you can do on any of those except replace them.

      One thing to remember on a hot water heater is whether it has been flushed/cleaned recently (ie, do it every year) - if not, sediment can build up on the coils, insulating them from the water, meaning it takes more energy to bring the water up to temperature.

      Regarding the AC unit - how are you running it? In the summer, set it for about 77 degrees when at home, but raise it to about 85 when nobody is at home (reverse for winter) - DON'T TURN IT OFF. If you turn it off, the house heats up (or cools down in winter), and it takes that much more energy to bring the air, and EVERYTHING ELSE in the house, including the walls, back down to the proper temperature. Remember as it warms up/cools off, adjust the temperature accordingly to raise/lower it - so that the outside temperature keeps your house comfortable. One other thing - make sure you don't have any "leakage" or drafty areas - break out the weatherstripping/caulk, and go to it! Also - do you have a combo A/C and swamp cooler (or separate heater/cooler units) that use the same duct works? If you do, then there are probably auto-dampers to shut the air flow off from each unit when one is in use, but not the other. If this is the case, check to make sure those dampers are working properly, and shutting off the air flow - no sense in cooling or heating the neighborhood (this also goes for fireplace flue dampers - shut 'em!). Also, if you have a "whole house" fan (which vents air from inside the house through windows and into the attic), that it's damper is shutting when it is off (and don't turn it on when the AC is on).

      Those are going to be your main energy wasters. The other appliances about all you can do is replace them with newer appliances (main the fridge - if you stove/oven is using a lot, then don't worry too much about it, because it isn't on all the time).

      One more thing about parasitic loads - if someone is stealing the power, check to see how it is hidden, and where it is going. If it is a neighbor, it may be for grow lights (work out a trade?)...

      • in fact, what might be easiest (but make sure you have surge protectors for computers and electronics) is to simply turn off the breakers.

        I've done some of this, but to be honest I can't really say that I've gone to that much trouble at this point. Also, my breaker box is completely insane with circuits going all over the house. Too many past "homeowner jobs".

        If you turn it off, the house heats up (or cools down in winter), and it takes that much more energy to bring the air, and EVERYTHING ELSE in the house, including the walls, back down to the proper temperature.

        This is interesting... you think it takes less overall energy to maintain the temperature through an entire day, rather than turn it completely off during the day and then bring it down in the evening? I would have thought the opposite. Obviously, at some point it must make sense to turn it off (keeping it off for a month, for example).

        Anyway, the A/C obviously sucks power like it's going out of style, but even when I don't run the A/C the power level just seems way too high. I have my suspicians that it might be my pool's pump motor.

        But overall, you're right. You can tell a lot through the use of the circuit breakers and some investigative work, but I've been too busy/lazy/childrened to track it down. :)

        I should also mention that I live in California where power rates are beyond out of control.

        • Regarding the breaker box - were these past "homeowner" jobs that you did, or the previous homeowner (or the current one, if you are renting)? I ask this because of my statement about the nail through the wire - the owner of the house was a "do-it-yourselfer", and I have the feeling that he may have accidentally driven the nail through (can't ask him now - he passed away about 3 weeks prior to the house burning - talk about tragedies to befall a family), having seen his handy work on other projects in a house me and my wife rented from them. So, the statement about a high resistance issue is something to think about.

          As far as the A/C is concerned, I was told this by a trusted and respected A/C repairman I personally know (an old irish dude that will talk your ear off if you let him - but is one of the most honest men I know). I tried this on the house that I rented from my brother-in-law's parents, which had two large A/C units (big house - 3500 sf or so), and cut my bill way down. It makes sense (think of a bicycle - how much effort it takes to get going, but how much easier it is to keep going, or to speed up).

          If you have a pool pump, then there is another power drain. I don't know much about pools, as I don't own one yet, but I do know that /. had an article on a guy who was using a homebrew Linux system to monitor and control the pool pump and chemicals in his pool to help save money, as well as to keep the pool properly maintained. Look into it - pretty involved project, but might be worth it.

          One thing I forgot to mention (though you are probably doing this) is to remember to only use lights when you need them, shut them off when you don't. Also, you might look into compact flourescents for certain lights. For those lights where CFs won't work, try to put in electronic dimmers (ie, the ones that vary the cycle of the current going through the bulb, rather than use a rheostat, which wastes the energy as heat), and dim them as needed (like at night when you want to provide a bit of light for a hallway or something).

          I don't know what you are paying in electricity there in CA, but here in Phoenix, AZ - my bill hasn't been much over $200.00/month, the entire summer, and that is with two heatpumps (while expensive to buy - heatpumps are supposedly more efficient than AC/heater units - so you might look into them). Of course, like I said, I don't have a pool pump...

          • I don't know what you are paying in electricity there in CA,

            I'm almost embarrassed to tell you, but my last month's bill was $422 for 1,967 kWh. That should go way down now that it's cooling off, but I'm sure that no more than $100 is A/C. I *really* should care more about getting it down, but I bought the house about 1.5 years ago as a fixer upper, and there have been much larger fish to fry every weekend. :)

      • Regarding the AC unit ... DON'T TURN IT OFF. If you turn it off, the house heats up (or cools down in winter), and it takes that much more energy to bring the air, and EVERYTHING ELSE in the house, including the walls, back down to the proper temperature.

        I'm pretty sure that is wrong. I'm lazy and only found one source here []. It says:

        "It is a myth that it is cheaper to keep a house cool all the time than to cool a house that has had the air conditioner turned off or set to a warmer setting for part of the day. It actually takes less energy to run an air conditioner hard for a short time than to run it over a long period of time."
  • by anthony_dipierro ( 543308 ) on Wednesday October 16, 2002 @04:54PM (#4464437) Journal
    Especially for retrofit situations? All outlets can be X-10 managed, but this doesn't say anything about actual power consumption. I'd like something at my breaker box to measure the actual Kilowatt usage on the different circuits. Also it needs to be something passive, so if the computer goes down the system still needs to work perfectly (and then can poll the devices when it comes back up).
    • Call your local power company and ask if they will give you an old electric meter..There are piles of old meters at the dump as the utility changes to meters with remote reading capability.

      Mount the meter in a box with a plug and an outlet.. Take the reading of the meter

      Plug in your device, see what the meter reading after 24 hours. Subract this from the first reading you took.

      Result is the KWH used by your device averaged over 24 hours. You can obviously use a longer or shorter time period, as appropriate to the device.

      For 120 V devices, wire between either one of the hot meter legs and the neutral. For 240 V devices, wire between the 2 hot legs. Don't put 240 V on the meter between a hot and the neutral leg!

    • Very little (it seems) exists:

      Sean Adams Laser Meter Reader []

      There are also a couple of other links on that page - basically it is a "meter reader" that counts the pulses coming from the spinning disk in the reader (for some reason, meters in America use spinning disks, even if they are digital - this probably isn't the case everywhere - the link to the British dude, when it was up and I visited - showed what appeared to be a fully digital meter, no mechanical parts). He has it hooked up to a Linux box that reads these pulses via the parallel port.

      Such a setup, while not as advanced as what is being offered by Obvious (which seems to allow for monitoring of multiple circuits and other such niceties - which would be cool to do, because then you could get the monitoring down to circuit, and almost device, level), would still be useful for a homeowner and such.

      What I am wanting to do, though, is figure out how digital meters work. The meter on my house is one of the digital/mechanical hybrids. I could use Sean's circuit, but there is a "plug" on the front, that looks optical in some regard, that the meter reader guy uses to interface a handheld data logger device to - I would rather be able to use that interface, since it is what should be used, rather than a clunky external laser and detector system (though I wonder what my power company would think - one thing I wonder, is if you can program/reset through that interface - they wouldn't like that).

      • I could always combine that with the other suggestion, and buy/find/steal a whole bunch of old electric meters and hook them up to each breaker (even to each outlet if I was psycho enough). Then use the laser system to read those meters.

        Of course at that point I'd have to consider how much power the actual meters/lasers were using. Not to mention I'd have to convice the inspectors that it was perfectly safe (or tear the system down and hide it every time I did any new electrical work).

        And then there's the question of just how much usefulness I'd get out of it. Probably not enough to justify the hassle, though setting up the laser system at the current meters would probably be worth it - they don't mention the actual prices, just that it's cheap.

        Thanks for the info.

  • by hopscotch ( 55221 ) on Wednesday October 16, 2002 @04:54PM (#4464442)
    For CMOS devices, the power consumed is proportional the TOGGLING of GATE STATES NOT the length of time that the device is energized.

    From a processor viewpoint, just saying the Linux consumes more power because the machine in on more misses an important effeciency of Linux.

    For friend of mine measured the CPU temperature for both Linux and Windows on the same machine.

    Linux ran at about 78F degrees. Windows ran at about 92F degrees. Same tasks for both.

    Hotter chip means more energy consumed and shorter chip life.

    Linux should get credit for measurebly more effecient use of cpu gates.

    • by stratjakt ( 596332 ) on Wednesday October 16, 2002 @05:42PM (#4464771) Journal
      > Linux ran at about 78F degrees. Windows ran at about 92F degrees. Same tasks for both.

      Same tasks? Pray tell, which tasks? vi vs. MS Word? 78F CPU temp is awful freakin cold. Was linux running in an IGLOO?

      You're comparing a linux CLI to Windows with a full GUI, and getting heat of the video card, extra proc time devoted to rendering.

      Compare the heat generated in the Q3 timedemo on both, and see if there's a difference with the CPU under a full load. There won't be.

      Bah to cooked benchmarks.

      Also, I've never seen a CPU vary that much from full idle to a full load.

      Either A) Your friend misapplied the ASIII and heatsink, B) Your friend is a liar, or C) You made this shit up knowing a MS slam would get you karma.
  • by ikekrull ( 59661 ) on Wednesday October 16, 2002 @05:20PM (#4464607) Homepage
    And I use Linux all the time.

    In fact, all our web-based energy visualisation products were developed and run on Linux, and the 3D energy visualisation work I do on this in my spare time:

    screenshot []

    is also developed and run on Linux.

    The devices we use to interface ethernet with meters are too lightweight to run linux, they simply provide a TCP-IP -> serial connection for the meter's RS-232/422 interface and an ethernet port for connection to a LAN.

    Many meters only support pulse-output, which does require a device such as this to count pulses, convert them to kWh or other relevant measurement, buffer these readings for some period and provide a interface for this data to be extracted, which is what this device is.

    It is nice to see multiple inputs for temperature etc, as energy consumption data alone often does not provide enough of a picture to make decisions that can really cut your energy peaks or identify areas of inefficiency.

  • Slow day? (Score:5, Funny)

    by f97tosc ( 578893 ) on Wednesday October 16, 2002 @05:23PM (#4464635)
    I don't know which is less interesting; that somebody makes electricity monitoring equipment that runs Linux, or that somebody managed to exchange a drive on his Mac.

    Please put up something more thrilling. Otherwise I might have to return to work.

  • Use Linux to Reduce Your Power Bill

    Bill, Use your Power to Reduce Linux.

  • The Kill-a-Watt (Score:5, Interesting)

    by ChicoLance ( 318143 ) <> on Wednesday October 16, 2002 @05:38PM (#4464750)
    Recently, I found a little personal power meter that you plug into the wall, and the device you want to measure in front of that. It then shows the amount of kWh that device is used. It's a stand-alone device, and runs between $40-50.

    It's called the Kill-A-Watt [], and is available from ETA Engineering [], CCrane [], and Radio Shack []. .

    I'm not involved in this, but just bought one, and it's answered a bunch of questions about how much everything uses. Interesting!

  • I steal power from BC Hydro to run my marijuana-grow-operation.
  • by Billly Gates ( 198444 ) on Wednesday October 16, 2002 @05:52PM (#4464874) Journal
    Because I do not use Linux. I use Emacs. I just wish I had a good selection for linux based editors for Emacs though.

  • machines rather than the new portable heaters (P4's) would give enough power savings.
  • This device sounds great, but what many people I know and myself have been looking for is an affordable device which you plug in to a power outlet, then plug something (say, a computer) into the device, and get a simple readout of how many watts are being used, then we could use Ohm's law to find how many amps are in use. This would be extremely convenient for testing the real power usage of new PC components, major appliances, etc.
  • I mean, we all know that in general, the TCO for Linux is cheaper than for other OS' for a variety of reasons.

    But what does this specifically have to do with Linux? This guy's talking about calculating ways to save power. That can be done under any OS.

    The title of this article is like saying, "Use Porsche's to get from point A to point B". Yes, you can use Porshe's to get from point A to point B; but you can also use any other car.
  • My power bill is *higher* because of Linux. I'm crazy and have multiple servers running about the house.

    However, a few of them are Pentium III units, so my gas bill (for heating) has dropped like a rock.

    I just wish it was equal to the amount my power bill went up. :-)

    The apartment stays nice and warm. If I lived in Alaska, this would not be a bad thing. But in Sacramento, CA... well, I like my home sauna, let's just leave it at that.
    • I concur.

      The weather here in Ohio is starting to get chilly. When I had a couple of friends over the other night, one of them remarked to me "Man, why is your door open? It's -cold- outside. Why don't you shut it and turn on the heat?"

      I then gave him a brief tour of my furnace: A couple middle-of-the-road FreeBSD and Linux boxen, the slothly Windows machine in the corner, more than 100 pounds of fan-cooled UPS, an extraordinarily warm SMC 10/100 switching hub, HP Laserjet III, an old Scanjet IIcx, 19" monitors, 20" TV, and a stereo that draws a couple hundred Watts at idle.

      I had him hold his hand in the (quite warm) exhaust stream from the BSD machine for emphasis.

      I then told him that if it did get much cooler out, I would shut the door, but would leave the thermostats alone. My usual trick, which I expect to work fine until December or so, has been to use a fan to circulate heat from the living room to the rest of the apartment.

      And even after the snow flies, I'm not sure I'll be switching on the electric baseboard heaters. It seems like it'd be so much more fun to keep the TV on, and the recessed lights above the kitchen sink and range and in the bathroom could stay on more often. If things are still cold, I'll start firing up hideously-inefficient DJ lighting gear until it it warms up, and enjoy the technicolor splendor in the meantime.

      Technology is highly underrated as a source of heat in cooler climates. It's also "free" heat, if it's a device you'd leave on whether or not it was cold in the room.

      All this for ~$60/mo (or about twice that in the month of July, with AC and circulation fans going 24/7).

  • Yeah, its great for companies,
    but for residential applications?

    How about this?
    A programmable thermostat with a
    $ meter.

    Of course it wouldn't be exact, but
    it might teach a few people (myself included)
    that turning my thermostat up those last two degrees makes a huge difference in my energy bill.
  • by Glabrezu ( 215236 ) on Thursday October 17, 2002 @08:41AM (#4468287)
    Its amazing what a single comma might do...

"Of course power tools and alcohol don't mix. Everyone knows power tools aren't soluble in alcohol..." -- Crazy Nigel