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Technology

Wireless Internet In An Off-Grid House 425

Posted by timothy from the just-sippin' dept.
matt20 writes "This is an interesting article of a family living off-grid using solar panels. In such a setting, every watt adds up. The typical home computer and monitor use almost 150 watts. What is the best computer arrangement in such a setting? Here is what worked best for them. Anyone know what percent of our national power is used on computers? Should we be thinking wireless on laptops?" Even on-grid, this article raises some good points about power consumption and convenience.
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Wireless Internet In An Off-Grid House More

Wireless Internet In An Off-Grid House

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  • Home DC power (Score:4, Interesting)

    by bluegreenone ( 526698 ) on Monday August 05, 2002 @09:58PM (#4015820) Homepage
    With the number of devices in the home that now use DC power, I always thought it might save energy to have one large AC to DC transformer for the house, rather than having "wall wart" adapters for each device. Even when the device is off that wall wart is using energy(feel it, it's always warm). Why not have a more advanced transformer that could adjust for load, and run DC through wires to the whole house. Plus, no more problems trying to plug 2 wall warts into adjacent spots on a power strip!

    • Re:Home DC power (Score:4, Interesting)

      by ArchieBunker ( 132337 ) on Monday August 05, 2002 @10:02PM (#4015839)
      Most devices today use switching supplies which are more efficient and evidently cheaper to build than a transformer. DC was common at the turn of the century and even into the 40s in some cities. AC is much better for distributing power, thats why Edison lost.

      • Re:Home DC power (Score:5, Informative)

        by zenyu ( 248067 ) on Monday August 05, 2002 @10:48PM (#4016024)
        AC is much better for distributing power, thats why Edison lost.

        No, high voltage is much better for distributing power. Changing voltages used to be much harder with DC. It may still be for really high currents and voltages, I dunno.

        The savings at high voltage are just a matter of V=I*R & Power=VI

        VI=I^2*R

        So if you want to minimize the power lost over a transmission line you want to make the current(I) as small as possible, but you still want to transmit a lot of power so you raise the voltage. Once you the electricity near conducting stuff you want to minimize the voltage so that it is less likely to arc and jump through another conductor, esp if said conductor is a person or pet.

        With AC it's easy to make transformers that are 99.99% efficient, so you can have all these gradiations of voltage for different levels of safety and effeciency. (Easy but these things are still big. Not your average wall wart.)

        Switching transformers are used on things like your laptop, but not your average 802.11b AP. Those use a conventional wall wart and a very inefficient voltage regulator to get the voltage to exactly 3.3V or 5V or whatever. Even those laptop transformers aren't that efficient, though definately lighter and probably cheaper than the equivalent conventional transformer.

        A housewide transformer with 5V, 6V, 7.5V & 12V leads might or might not be more efficient, but I'd love it for the conveniance and clutter avoidance potential. Something like open feeds along the wall that you could just snap your device cord to. Maybe made out of some high tension wire like they hang those halogen lamps from sometimes. It could be really slick. It would only need five wires for all those voltages, and you could even make a +/- 6V supply for your electronics projects using the 0, 6 & 12 Volt leads... You also get a 1V, 1.5V, 2.5V, 4.5V and 7V out of those, maybe 2 of those are useful for battery replacement devices. Maybe a 9V lead would be useful too, that would get you the rest of the 12 V battery voltages.

        • No, high voltage is much better for distributing power. Changing voltages used to be much harder with DC. It may still be for really high currents and voltages, I dunno.

          Entirely correct. With the advent of high-power semiconductors, it is becoming possible to efficiently step down DC voltages for power transmission [techreview.com] (Tech Review article, full text is unfortunately "premium content"). With DC transmission, considerable savings can be achieved because fewer conductors are needed - one DC line can be stepped down into a full array of AC voltages and phases for customer use.

          Edison was still wrong, though - DC was entirely impractical in his time

      • Re:Home DC power (Score:5, Funny)

        by flacco ( 324089 ) on Monday August 05, 2002 @11:16PM (#4016101)
        AC is much better for distributing power, thats why Edison lost.

        I thought it was because that sadistic cunt electrocuted a circus elephant with AC power in order to scare the public into believing it was more dangerous than AC.

        Rot in hell, Edison.

        • Re:Home DC power (Score:2, Offtopic)

          by laserjet ( 170008 )
          was it an elephant? I thought it was a horse. Either way, you are right that is just plain wrong and sadistic.

        • Re:Home DC power (Score:2, Informative)

          by Admiral Llama ( 2826 )
          Edison was asked what was the best way to kill someone, and he had suggested AC current because he wanted to get an edge on his competitors over at Westinghouse who were pimping AC current. This is literally where the electric chair came from. Nige guy, huh?

          The good news is that his bid lost out, however we still fry criminals because of Edison's recomendataion regarding the lethality of alternating current.

        • Re:Home DC power (Score:2, Informative)

          by The_Hiro ( 230357 )
          Actually, Topsy was due for an execution by hanging (she had killed three people in as many years), but there was public concern over the inhumanity of hanging her. Edison stepped up to the plate with the intent of a) making AC power appear dangerous, and b) demonstrating the effectiveness of electrocution as a painless form of execution [roadsideamerica.com].

    • Re:Home DC power (Score:2, Interesting)

      by qwerpoiu ( 532823 )
      Correct me if I'm wrong, but wouldn't the fact that devices use different voltage make this impossible?
    • Yes, but what voltage would the DC power run at? All of these different devices tend to need different voltages. I seem to recall that changing DC voltages was rather harder than with AC -- I mean, that's why the power grid runs in AC, right?
    • With the number of devices in the home that now use DC power, I always thought it might save energy to have one large AC to DC transformer for the house, rather than having "wall wart" adapters for each device. Even when the device is off that wall wart is using energy(feel it, it's always warm). Why not have a more advanced transformer that could adjust for load, and run DC through wires to the whole house. Plus, no more problems trying to plug 2 wall warts into adjacent spots on a power strip!

      I nominate this guy for President!!!

      < insert "presumptuous arrogant American" rhetoric here >

    • Well, a lot of homes that run mostly on solar power already have a lot of 12VDC wiring in the house, since 12VDC is what typically comes from the panels and/or the batteries. There are of course 12V lights, both incandescent and fluorescent (oh, and LED too), 12V refrigerators and other appliances, and 12V can easily be used for anything that was designed to be plugged into a car cigarette lighter.
    • Why AC to DC? The power supplied by photovoltaics is already DC. You just need a switching power supply to make sure you're getting the voltage you need (not all of my DC equipment/wall warts supply the same voltage!)

      I'd need (just looking at the power strip, here) a 3v, 7v, 9v, 12v, and 15v DC outlet just to take care of the USB hub, the network hub, the DSL "modem," the regular modem (for failover), and the DLT.

      AC is great for transmitting power over long distances, but any time power is used within a short distance of the generator, DC is more efficient in most cases (as there's no need to convert voltage *again*.)

      And in some cases like transmitting power under/through bodies of water, high voltage DC is used to get around certain electrolytic effects.

      I'm already using white LEDs in certain applications for lighting, and plan to expand that. I've already cut the computers' electrical usage as low as I can without sacrificing performance. I don't use a CRT any more - LCD is less than 5% the power that the CRT used to draw.

      I wonder what the real numbers are on efficiency in the wall wart equation. I know that some data centers use distributed DC power instead of a separate AC-to-DC converter inside each server (Sun's Netra boxes spring to mind.)
    • I grew up in a 12v DC household.
      We had a bank of half a dozen (or more, it varied) old automotive batteries in parallel which were charged by an old (1919) DelcoLite generator whose original 36v coil had been rewired to produce 18v. We ran it below optimal RPM's to get about 14v. It had sat in a field for 30 years used for target practice before we got it and rebuilt it with an air-compressor piston (connecting rod cut and extended with a pair of bolts welded onto it), an aluminum pot with the bottom bashed out of it as an air duct for the head, a Land Rover instrument panel, and an old motorcycle carburetor. We primed it with gas but it actually ran off kerosene.
      We could run for about a week between charges until we got solar and then we only cranked up the generator about every 6 months or so when the cloud-cover had been too heavy.
      All lights were ordinary 60w bulbs but anything with a motor was either designed for RV's or rewired. (Fridge was kerosene then butane).
      All computer equipment was laptops and portable printers (12v or less).
      I made a few bucks on the side for quite some time designing 12v adaptors for laptops that took more or less than 12v and making them fit inside in whatever space the manufacturer had left over!
      The soldering iron I used for this was a piece of broomstick and a twist of coat-hanger wire holding a real soldering-iron tip which was wrapped in a heating element salvaged from an incubator.

      And I really did have to walk/hitch-hike 20 miles to school every day in the pouring rain (or boiling sun)!
      But that's another story...
    • What about overclocking the AC in your house so it doesn't run at a measly 60 Hz like this guy did [bbspot.com].
  • From a purely thermodynamic point of view, it's always much more efficient, energy-wise, to have a wired connection, rather than a wireless... Particularly because wireless internet is omni-directional, so the other 359 degrees horizontally, and the other 359 degrees vertically that aren't line of sight from you to the transmitter are essentially wasted.
    This is why FM and TV broadcasting uses multiple-bay antennas... even the omni-directional ones. By directing less energy straight up (who lives _above_ a tower?!) and less energy straight down (who lives directly under a tower?!) they can send more energy out horizontally, extending their range. The same applies to wireless networking, just that it's at a higher frequency... and thus even more directional.

    -T

    • They're talking about a wireless uplink, not wireless to the devices (because they don't have any wires going to the house). In this case you don't need to be omni-directional, because neither your house nor your upstream provider are going to wander around. Of course, air and terrain features don't transmit as well as fiber or coax, so you'd still be wasting some power. On the other hand, you might expend more energy trying to maintain a wire than you waste with wireless.
    • it's always much more efficient, energy-wise, to have a wired connection, rather than a wireless... Particularly because wireless internet is omni-directional, so the other 359 degrees horizontally, and the other 359 degrees vertically that aren't line of sight from you to ...

      Does that mean all the neighbors will read my precious spam?
    • Wireless connections are almost always directional at the endpoint, usually using microwave type frequencies. The "wasted" range is something more like 15-30 degrees, not the 359 you stated.
      It's also possible for the transmitters to be intelligent, such that on clear days they transmit at lower power. They increase power as necessary to cope with atmospheric conditions like snow, rain and dust.
      In fact, when you order wireless Internet or telephone access you will almost always have a sire survey completed before they let you sign a contract. The survey looks for a spot on your building/property where they have line-of-sight to the

  • on home-based solar power... (Score:3, Interesting)

    by jeffy124 ( 453342 ) on Monday August 05, 2002 @10:03PM (#4015841) Homepage Journal
    recently my local news had a story about a household that used solar. they actually sell their excess to the electric company, to the tune of something like $300 a month. apparently it paid off the equipment in about two years, and now they just collect as profit!
    • Pretty much anyone can do this if their power meter doesn't have a device on it which prevents it from spinning backwards. If you use little enough electricity, when it gets to the sunny part of the day your meter will take off KWH from the bill.

      However, the legality is shakey, unless the eletric company agrees to let you do this. Some actually do let people do this, but for obvious reasons the setup must comply to many safety standards- not just be some homebrew AC generator.
    • You're going to sell electricity back to the grid at the same price at which you buy it. Unless you pay $300 now, you're going to have to generate a hell of a lot more than double what you use to make that kind of money. Solar is great, but it would take a lot of panels to generate that kind of power, and panels can get pretty expensive.
      • You're going to sell electricity back to the grid at the same price at which you buy it.

        This isn't always the case. Some areas have time-sensitive pricing schemes where electricity is more expensive in the middle of the day (when air conditioners run) than at night. If you are gone at work during the day, you can generate power and sell most of it at the higher-priced rate. When you are at home at night, using more power and generating none, you buy it back at the lower rate -- such a deal!
        • Interesting.

          Theoretically, If you could store energy with enough efficiency, you could make money buying and selling from/to the grid at different times in the day. How big of a difference in price are we talking about here?

          • Time of day (Score:3, Interesting)

            by BCoates ( 512464 )
            Indeed you could... the hard part is storing enough energy for a few hours with small enough loss/expense to to profitable.

            There's a plant [usbr.gov] at the twin lakes resivoir which pumps water uphill at night and generates power during the day.

            They have much nicer bathrooms than are avaliable at the nearby national forest campsite, too :)

            --
            Benjamin Coates
    • I'm a big proponent of Solar energy, but come on. Payed off in two years and NETTING $300/month in payback? MAYBE if you include the energy they use in that figure, and if that is quite a stretch.

      However yes, many locales do have this sort of net metering set up. You have to demonstrate that you can do it safely but it's just common enough that even utilities up here in Maine have policies on it.
      • At 7 cents per kw/h, even with a $3 rebate per watt (assuming $6 per watt overall cost), I calculated it would take 30 years to recoup the costs of a 1kw solar installation, in the Los Angeles area.

        Solar isn't cheap - add in the costs of inverter, permits, panels, and you're looking at a long-term investment. True, your costs go down as you add more panels (since much of your initial fixed costs can be shared by future panels) but the payback period will be about the same.

        It would be cheaper to just use less power.

        Also, in the LA area, the local power utility (LADWP) will not let you sell back power as a residential customer, if your solar array exceeds your power needs - you'd have to register as a power producer and pay connection fees/taxes/etc. And, as a power producer, you'd forefit the $3 per watt rebate, meaning your payback period would double...

        On the other hand, if you live in the middle of nowhere, and the power company wants to charge you $15,000 just to run power lines, then solar power looks like a bargain (even including the needed battery banks to store power, and generator for backup.)
    • Don't try this in Alabama. First off, I don't know if anyone has succesfully gotten Alabama Power to do net metering. Second, at $0.079/kWh you'd have to generate roughly 3.8MWh of electricity. Assuming 5 hours of full sun per day, you'd have to have 25kW worth of panels, which even at a cheap price of $4/W would be a cool $100k. And that's not counting the power you need for yourself. Thanks to our low electric prices, many houses here are heated and cooled by electric heat pumps, which can easily use 1MWh in a month during summer and winter (all 10 days of it).

  • That was quick (Score:5, Funny)

    by Clue4All ( 580842 ) on Monday August 05, 2002 @10:06PM (#4015852) Homepage
    Anyone know what percent of our national power is used on computers?

    Judging by the unavailability of this site, I'd say not nearly enough.

  • RTFA :) (Score:5, Informative)

    by vreeker ( 264162 ) <slashdot@opid.ca> on Monday August 05, 2002 @10:08PM (#4015859) Homepage
    Efficient Computing & Wireless Internet
    ©2002 John Bertrand

    A year ago, when we finally settled into our still incomplete solar powered house, we set up our trusty three-year-old computer. Then, having no landlines (electricity or telephone) we installed a wireless broadband Internet connection. So we were sitting pretty, right? Wrong.

    In fifteen years of home computer use, we have never just left the computer on all day. But times and uses have changed. Our computer has become more and more of an appliance rather than a specialty tool. In our new home, it became apparent that we needed it available constantly for Internet research and e-mail. Yet leaving the system on, even in sleep mode, used too much energy. Our fairly typical desktop system draws 180 to 190 watts.

    Flipping it off and on was too much of a hassle because of the almost 2 minute boot up each time we needed to check something. Besides, even turning it on and off as needed was a serious drain on our 1.2 KW PV system. Expanding our PV array (sixteen, 77 watt modules) was not an option because the present rack and wiring are maxxed out, not to mention the hassle of having to submit a new electrical permit application, complete with engineering stamp.

    The Search
    So I began researching notebook computers. Without a doubt, they would provide a much better energy use scenario. I wanted the lowest possible energy use in a quality unit.

    I have always purchased desktop systems from smaller companies that offer good quality parts for the money. I could always make changes later if necessary. But notebooks are a different animal, since they are more or less a closed package. So it is very important that it has all the functions you will need.

    For many people, the notebook can replace the desktop unit. So a 14 or 15 inch (36 or 38 cm) screen, 5 to 7 pound (2Ð3 kg) "desktop replacement" machine will work. For others, a really lightweight 3 to 4 pound (1.4Ð1.8 kg) unit with a 10 to 12 inch (25Ð30 cm) screen is fine, since the desktop unit is not being displaced, but supplemented and networked. The former will certainly save watts over a desktop unit, but with its built-in drives and large screen, will use considerably more energy than the latter.

    For us, keeping the desktop unit for graphics-intensive tasks seemed desirable, since the screen is larger, and CRT monitors generally handle graphics better. So I researched what was available in the smallest of the Windows-based notebooks.

    Our personal parameters included finding a highly rated, quality product from a well-known company (such as Dell, IBM, Gateway, Micron, Sony), long battery life, no built-in drives other than the hard drive (but with an attachable CD/DVD drive for loading programs, etc.), at least 256 MB RAM and a 20 GB hard drive, a touchpad pointing device, and a high quality graphics card that will not drop frames when playing a DVD movie.

    I began looking more than six months ago. Because of their customer satisfaction record, I was somewhat predisposed to look most seriously at the Dell offerings, in particular the Latitude L-400. But it was weak on graphics and, having been on the market quite awhile, was not tops in energy efficiency. We came close to trying a Sony unit available from Costco for less than US$1,000, but it only had a 10.4 inch (26.4 cm) screen, older chip sets, and mediocre graphics. That finally kept it out of the running.

    A Small Gem
    In November 2001, Dell introduced a new model, the Latitude C-400. It was much like the earlier L-400, but had updated processors (866 MHz or 1.2 GHz, running on half a watt), a new generation of energy-saving Intel support chips (830M), graphics adequate for DVD movies, both a touchpad and a pointing stick, and some other goodies I found desirable.

    I watched the prices, including the Dell "refurbished" units. In January, after the Christmas rush was over, I kept close track and finally bit on a good offer. (Remember, if you buy on the phone rather than off the Net, you may be able to negotiate for even better than the current sale prices, but beware of the frustrating sales-speak even from reputable firms.)

    This particular model best met our needs. The US$2,300 price is in the midranges, with basic economy models available around US$1,000, and corporate road-warrior models well above US$3,000. (Note: laptop prices continue to fall, so you may be able to do even better by the time you read this.)

    In terms of energy usage, though, this model has to be near the lower limit. We measured usage with a Watts up? meter. The meter isn't extremely accurate when measuring loads drawing less than 20 watts, but it's close enough for general use. In any case, the C-400 uses just 15 to 18 watts when in regular use.

    This figure, when compared to the desktop system, is cause enough for joy. But when we close the case, putting the system in standby (it goes to hibernation in 15 minutes, or whatever you want to set), the usage is too low to measure with this meter.

    Wireless Internet
    When it comes to broadband Internet service, there are three major routes and one minor route. Leading the charge these days is cable modem service from the cable TV companies. This is followed closely by DSL (digital subscriber line) service from the telephone companies. Satellite service from the two satellite TV companies has made inroads mainly where the other two services are not available.

    Finally, in a few areas, ISPs have established fixed wireless service, which uses a line-of-sight radio link between their operation and subscribers. The radio signal is in the same frequency range as a microwave oven, and can be fairly characterized as a "microwave link." It conforms to the IEEE 802.11b standard used for wireless networking within the home or office, and is theoretically capable of 11 MB per second information transfer. A radio transceiver and small antenna are required.

    We had a choice of going to Starband satellite service or Interlink Hawaii (local ISP) fixed wireless service. Starband was just becoming available with no track record, high upfront costs of more than US$1,500 (installation is less expensive in the continental U.S.) and a monthly cost of US$70. Interlink's fixed wireless service had been around for several years, had an installation package of US$500, and cost US$50 a month. Needless to say we went with the latter, which uses a Breezenet Pro.11 radio.

    Overall, we have been very satisfied with the service. When our radio was failing after less than a year (it is leased and was used), they were slow to replace it. But otherwise, we have had mostly speedy surfing, with very little downtime. And being a local company, they are usually easy to work with. Power draw of the wireless system is 1 to 2 watts.

    Over a typical day of turning the system on first thing in the morning, using it for about 5 hours off and on, with it in standby or hibernation the rest of the time (about 7 to 8 hours), the total watt-hours used is 84. That's equivalent to about 25 minutes use of the desktop system! If it is on standby, the C-400 comes back to full use in a few seconds. From hibernation, it takes all of about 15 seconds. That's very tolerable for an appliance.

    Other Considerations
    As a selling feature, notebook manufacturers try to maximize battery life, that is, the amount of time their computers will run on a single charge. Since we keep the unit plugged in so much, battery life is not critical, but it's still a good indicator of system efficiency.

    Within groups of similar computers, the longer the--battery life, the more efficient the computer is. This comparison works best if independently measured, but manufacturers' estimated time is usually a good rough estimate. Just remember that this measurement applies within a given category of processor, screen size, battery size, and peripherals.

    While it may seem good to keep the battery charged up, it is also good to let it cycle some. So don't leave it plugged in all the time. Unplug it every once in a while, and let it discharge fully before charging again. If NiCd is used, the battery should be fully discharged routinely (several times a month) and then refilled. If the battery is NiMH or lithium technology, it isn't as important to fully discharge the battery routinely, but it should be fully discharged once every month or two. Most modern notebooks use the NiMH or lithium ion batteries.

    Keyboards are also a concern with notebooks. The great portability of a 3+ pound (1.4+ kg) unit is somewhat offset by a slightly smaller keyboard, not to mention a few keys in somewhat different places. I find the tradeoff to be acceptable. You may not. The larger notebooks do have equivalent keyboards, but not exactly ergonomically correct ones.

    Another alternative is to buy a notebook with an auxiliary keyboard port. Then you can use a standard keyboard ordinarily used with a desktop unit. Most larger notebooks have similar ports for a mouse and monitor. Others have auxiliary ports in docking stations so a notebook can emulate a desktop computer.

    Of course, not everyone is in a position to part with more than US$2,000 to save some watt-hours. But it was worth it for us. The cost of adding more PVs and related equipment to have our desktop unit available full time would have exceeded what we spent. Almost any notebook computer, with the ability to handle similar tasks, is far preferable to a desktop system for energy conservation.

    As time goes on, more models will use the new energy-saving chip sets. Even the model we bought is now available as refurbished. (Usually they are returned within 30 days after purchase and like new.) I just saw one similar to ours for less than US$1,600.

    Although I was researching PCs, Apple's latest notebooks are also quite frugal. I managed to get permission (not without a questioning look from the store manager) to measure one of the 600 MHz G3 iBooks, and it came in at around 20 watts.

    Dessert
    The rest of the changes to our computing scene may seem frivolous. Still, if we see the computer as an appliance, the handier the better. We added a D-Link wireless router (Model DI 713P, US$140, 7 watts) that gives us the ability to use the laptop almost anywhere in the house. It also connects the two computers together and provides good Internet security from hackers. (Incidentally, software can provide good protection also, but it's not as good as the hardware solution in a router.)

    The setup of the router was very time consuming. I have read of others who have had an easier setup, and still others who have given up and returned the unit. So I have mixed feelings about it. Setting up a single computer would be easier, as would setting up with only a newer operating system.

    The manufacturers need to provide more information than we received. Usually I like to exhaust my own resources before calling tech support, but I still spent quite a few hours sorting things out with both the router tech support and my Internet service provider tech support.

    Energy-Sipping Computing
    Everything needs to be on switched outlets for efficiency, preferably surge protected outlets. On one switch, we have the fixed wireless radio and the router, which have no internal switches, and the printer, which does have an internal switch (usually turned off). The notebook computer is on another, and the desktop computer and scanner (usually turned off) on another. So we can handle almost any combination of computing needs without having unnecessary equipment sucking electricity.

    In spite of the less-than-satisfactory router experience, our new computer system has been a great convenience. After half a year of no computer availability in our off-grid home, we learned that our desktop computer was just too much of an energy hog to work for us in our limited-energy environment. Having cast about for a solution, I believe we found a good one with our 3 pound (1.4 kg) notebook computer. It draws only 15 to 18 watts when being used, and practically none when in standby.

    We no longer have to feel guilty when using a very important appliance. It is handy anywhere we are in the house, anytime we need it. And so far, we have run the generator hardly at all. Aloha.

    Access
    John Bertrand, PO Box 811, Holualoa, HI 96725 caber@kona.net

    Dell Computer Corporation, One Dell Way, Round Rock, TX 78682 800-915-3355 or 512-338-4400 csd@dell.com www.dell.com Dell Latitude C-400 notebook computer

    Alvarion, Inc., 5858 Edison Pl., Carlsbad, CA 92008 760-517-3100 Fax: 760-517-3200 sales-north.america@alvarion.com www.alvarion.com Breezenet Pro.11 radio

    D-Link U.S.A., 53 Discovery Dr., Irvine, CA 92618 800-326-1688 Fax: 949-753-7033 sales@dlink.com www.dlink.com D-Link DI-713P wireless router

    Some Useful PC Computer Web Sites
    Major Notebook Manufacturers:
    www.dell.com www.gateway.com www.ibm.com www.micronpc.com www.sonystyle.com www.hp.com www.apple.com

    Networking Info:
    www.wown.com www.pcworld.com/features/article/0,aid,86935,tk,cx b,00.asp

    Internet Security Software:
    www.zonelabs.com Zonelabs' Zone Alarm is a free download; the Pro version costs US$40. The free version has been highly recommended and has been used by the author. The Pro version has more bells & whistles.

    Notebook Power Management:
    www.extremetech.com/article/0,3396,ap n=2&s=1005&a= 24385&ap=1,00.asp This is an article at the Extreme Tech site and may be available for a limited time.

    Evaluations & Comparisons:
    www.pcmagazine.com www.zdnet.com www.techtv.com www.pcworld.com www.practicallynetworked.com

    Shopping/Price Comparisons:
    www.pricewatch.com www.pricegrabber.com www.techbargains.com www.amazon.com www.cnet.com

  • More power, Scotty! (Score:3, Informative)

    by shoppa ( 464619 ) on Monday August 05, 2002 @10:08PM (#4015860)
    Anyone know what percent of our national power is used on computers?

    I don't know the number, but the trend is disturbing. I would have naively thought that as

    • computers get more and more computational power
    • while their power requirements per computational power decrease
    that the number of computers needed would decrease. Instead, the number of computers seem to be multiplying. Even I'm guilty of it; add a firewall here, add a web server there, add a NAS box in the room.

    I do appreciate your desire for a low-power consumption box. And I do appreciate that your computing solution only involves a single box. Good luck in your search.

  • Home Power magazine (Score:5, Informative)

    by chrysrobyn ( 106763 ) on Monday August 05, 2002 @10:15PM (#4015891)

    For those unfamiliar with Home Power, this is a typical article from them. Their typical monthly magazine has an article about "Solar Guirrilas", or people who decide to put up solar panels, plug them into the "grid" (municipal power supply) and not get the permits for it. They also toss in a "I use solar panels and/or a wind turbine to make 10-100% of my own power, using/shunning batteries in the process" article that makes one think that such a thing is so great, why doesn't everybody do it? (The answer is in a very attractive tabular form that has a dollar figure at the bottom.) Recently, although I don't think it's always, they have had an article on how easy it is to convert your existing car to an electric one. As near as I can tell, it's a thinly veilled advertisement for one of their sponsors (and possibly an editor, sheesh I wish I remembered why I suspected that).

    Okay, cynicism aside, because that's what slashdot's all about, Home Power is actually one of my favorite magazines. They help me think about what I can do in my day to day life that may have an impact on the environment. I'm not likely to blow $20k on solar panels on my roof, not likely to get a wind turbine that always needs maintenance during the worst times even after I get approval from my homeowner's association, and I'm not even likely to convert my car into a $3k worth of batteries beast that maxes out at 65mph. I did, however, convert all my light bulbs to fluorescent and blew the $20 on the programmable thermostats. I'm even considering one of those insulating spreads that you wrap around the water heaters. Now if I could blow $4k on my car and make it a battery driven beast that could handke 85 as I commute down Parmer Lane in Austin...

    I dream of, one day when I'm rich off of my wife's stock options, building a house with solar panels on the roof and maybe a pretty, whirring wind turbine in the back yard while I contribute to urban sprawl.

    To pre-emptively strike against a good slashdot myth, yes, solar panels will pay for themselves. They earn back the energy that it took to make them (and start to net negative CO2) after 1-3 years of operation, depending on if you're in California/Arizona or Vermont, and if you ignore the time value of money, can earn their dollar cost back in 10-20 years, depending on costs, location and care.

    • Ignore time value of money? Okay, giant leap of faith that is utterly bizarre and wholy unrealistic. Are you sure your wife's stock options are worth anything? Toilet paper is remarkably cheap.

      I've looked at two issues. And there seem to be lots of articles like "Look at this product from this manufacturer. Buy it from this installer. Tabulate 'savings' based only on buying raw parts at wholesale." I was a bit disappointed, but it did seem that wind power might be doable/useful at my parents place.
      • Ignore time value of money?

        Interesting. I'd never thought of this... comparing (a) a $20,000 investment put into a financial instrument(s) vs. (b) an annuity based on the savings of electrical power. The general rule about the accumulationg from such things being greater the bigger the initial principal is would seem to indicate that (a) would win out.

        Of course, that leaves aside the complexity of calculating costs to the environment and taxing of resources. That's the problem with these things... we can shove costs onto the commons, and we get all sorts of problems...

    • FutureEnergies.com (Score:5, Informative)

      by horza ( 87255 ) on Tuesday August 06, 2002 @03:46AM (#4016676) Homepage
      Recently, although I don't think it's always, they have had an article on how easy it is to convert your existing car to an electric one.

      I've spoken to a few people that have done it, and are very happy with the result. They are faster than conventional cars, apparently because the electric motors give more torque. Here is one home conversion [futureenergies.com] that does 100mph and cost £6,000 to convert. Running cost works out at £0.018 per mile.

      I'm not likely to blow $20k on solar panels on my roof

      Expect prices to drop. There are companies like BP pouring millions into research. Current solar technology is maxing out around 20% effecient, and uses rather nasty substances to make, so the hunt is on for alternative fabrication materials and methods (eg here [atsautomation.com]).

      I did, however, convert all my light bulbs to fluorescent

      There are new energy efficient light bulbs that run on under 20 watts, are blindingly bright, but best of all now cost less than (afaicr) a couple of quid.

      I'm even considering one of those insulating spreads that you wrap around the water heaters.

      Essential. Also look out for micro-CHP coming soon (CHP = Combined Heat and Power). CHP is in wide use today in large buildings. Converting electricity to heat or vice versa is very inefficient, and you can get a max of 40% return. By producing both at the same time, you can get 90% return on the energy you put in.

      Phillip.
    • This Home Power sounds a heck of a lot like slashdot. Do they have a moderation system?

  • Which laptop did he purchase? (Score:4, Informative)

    by Pfhor ( 40220 ) on Monday August 05, 2002 @10:19PM (#4015911) Homepage
    I can't load the article, but from the copy and paste here, it doesn't appear to say which one he got (he just mentions apple's iBook as the last machine he looked at).

    I also just checked, and apples flat screen iMac has a max of 130watt power draw, which is quite impressive for a low power usage situation. I'm glad my college bought those to replace the macs, to counter balance the P4's they are putting in (in terms of power consumption).

  • Paradox of the Slashdot Effect? (Score:4, Funny)

    by lamour ( 49437 ) on Monday August 05, 2002 @10:27PM (#4015942) Homepage
    ok, someone explain this to me. For a site to get slashdotted, slashdot readers would need to click through to read the articles...but as a long-time slashdot reader, I know that nobody here actually reads the articles, so...what's really taking down all these web servers?

    • Re:Paradox of the Slashdot Effect? (Score:5, Funny)

      by boa13 ( 548222 ) on Monday August 05, 2002 @11:18PM (#4016110) Homepage Journal
      There are two kind of people on Slashdot:
      • those who read the stories and follow the links;
      • those who don't read the stories and comment on them.
      The two population are of course completely disjoint. I remember CmdrTaco saying sometime around when Slashdot began offering a subscription that the first one accounts for 80% to 90% of the users of the site.
      • The two population are of course completely disjoint. I remember CmdrTaco saying sometime around when Slashdot began offering a subscription that the first one accounts for 80% to 90% of the users of the site.

        So people who are karma-capped are just the best of the worst? Also... as a practical matter, you only really get to vote after you start commenting. Makes you wonder what the website is really for, doesn't it? =)

  • Solar Panel Ecology (Score:4, Interesting)

    by Anonymous Coward on Monday August 05, 2002 @10:38PM (#4015979)
    We did a study for one of my engineering classes recently about the power required to produce a solar panel as compared with the amount of power produced over the panel's lifetime. Turns out that manufacturing requires nearly 40% of the power the cell will produce over its lifetime. Kinda makes you want to look elsewhere, eh?
    • This is a great point. The proponents of alternative energy often ignore this important fact. It takes energy to get energy.

      This can't be ignored in determining whether some alternative is a net energy saver.

    • Re:Solar Panel Ecology (Score:3, Interesting)

      by ahfoo ( 223186 )
      I can do a study showing that in order to make a sandwich you have to consume a hundred thousand times the calories in the sandwich by including the growing of the vegies, the meat etc. Does that mean you shoudln't eat because it's inefficient? Have you ever considered that studies themselves are products of design that consume vast sums of energy to create? Studies are works of design and engineering. It's called social engineering. There is an agenda behind every study and the more it is disguised as scientific truth the more likely it is to be motivated by specific political interests.
      If you think everything you learn in school is true at face value, you're probably still in school.
      Anyhow, I'm a long haired hippy and I like to use lots of power. Like many long haired hippies I like my music loud and I use big power hungry amps to achieve that effect and I don't really care how much power they use. I also like halogen lights and neon signs and big lasers. I'm not against efficiency, but I think electricity is already quite efficient. Current generation PV may not be the best answer for terrestrial applications, but that's a restricted view of their utility from my broad minded long haired, though balding, liberal perspective.

  • biophotovoltics anyone? (Score:3, Insightful)

    by t0qer ( 230538 ) on Monday August 05, 2002 @10:41PM (#4015997) Homepage Journal
    I think the problem with current solar cells is they are hard to produce and less than efficient.

    I had a dream the other day about algea that could convert solar energy into electrical energy. I envisioned giant ponds of green murky water with evenly spaced rods to collect the electricity the little buggers give off.

    It's probably just a pipe dream, but considering our current biotech and genetic technology, is electricity producing algea possible? I mean we already have algea (or was it bacteria?) that live off of sulpher given off by thermal stacks deep below our oceans.

    Consider this...

    You can see the crystals on a solar panel with the naked eye. Very large, sort of wasteful. Can you see a single celled organism with the naked eye? Theoretically you could pack a whole lot more algea into a square inch that you could solar crystals.

    This is just a question, it's been buggin me for the last few weeks, and if anyone has an answer please share.

    --toq

    • Re:biophotovoltics anyone? (Score:5, Interesting)

      by BeBoxer ( 14448 ) on Monday August 05, 2002 @11:11PM (#4016087)
      Actually, they are developing hydrogen producing bacteria. Check it out. [ohio-state.edu] More accurately, people are working on using existing bacteria to produce hydrogen. But eventually genetic engineering will probably be used to up the efficency of the process. Once you have the hydrogen, producing electricity from it is pretty trival (burn it in a turbine or fuel cell).
    • An interesting idea...

      The trick is that you have to remember that when dealing with living organisms, there is a certain amount of energy required to support life and growth (if nothing else but to replace those organisms which die.) You would have to overcome that hurdle to efficiency.

      Another thing that many people don't realize is that the photosynthesis process begins with the movement of electrons. An incoming photon essentially excites an electron above the ground state, and the rest of the system acts to capture that energy. In photosynthetic systems, that energy is used to synthesize glucose. Using chlorophyll directly in photovoltaics may be possible, but would likely be more complex and perhaps even less efficient than traditional silicon PVs.

      And of course, you conveniently neglect the more "traditional" approach - why don't you raise algae, collect it, burn it, and use the heat to generate electricity? It's possible, although it may not offset the cost of the fertilizers needed to grow algae in those quantities.

      The real draw to a biophotovoltaic system would be cost-effectiveness, since it's likely that such a system would be much less efficient than a silicon-based system. However, it's hard to expect that you could somehow stick electrodes into a vat of algae and get electricity... although not impossible. To achieve this, however, would take some leaps in the current state-of-the-art in bioengineering and is not likely to happen for another 10 or so years.

    • Kinda like The Matrix...

  • actually (Score:3, Interesting)

    by jiminy ( 588565 ) on Monday August 05, 2002 @10:41PM (#4015999)
    my parents recently wired their home to use solar panels
    the house itself didn't actually get converted over, however

    all that was needed to allow normal function was an inverter
    it converts the dc to normal line voltage

    the excess power is pushed back onto the grid and due to recent legislation, they get paid for it

    needless to say, the electric bill is down tremendously...

  • TIAX study of power consumption by DP, comms (Score:4, Informative)

    by isdnip ( 49656 ) on Monday August 05, 2002 @10:50PM (#4016034)
    Answering the originator's question about how much power is consumed by computers and the like, we did a study for DoE last year. Note that it excludes home computers, focusing on business use, but this picks up the bulk of power consumption. NTIS.gov will sell you a CDR of report PB2002-101438 for $47. A PDF slide set summary is available at:

    http://www.tiax.biz/pdf/EIA-OffTelecom-TIAX.pdf

    One interesting conclusion:
    Commercial Office and Telecommunications equipment electricity consumption represents just under 3% of national electricity consumption, and a little over 1% of national energy consumption.

    Note that the report was prepared by Arthur D Little Inc.; TIAX acquired the group that did this study.
    • Commercial Office and Telecommunications equipment electricity consumption represents just under 3% of national electricity consumption, and a little over 1% of national energy consumption.

      It's funny how everyone focuses on how much energy computers consume. Computerization has brought about efficiency improvements in all areas of the economy that saves vastly more energy than the 1% they use. They provide a net benefit for energy usage, but somehow get blamed for blackouts.

      Still, I can't help thinking about how much electricity my computers consume. It's probably because the fans make so much noise and the monitors heat up the air in front of my face. It would really make more sense to try to maximize the efficiency of my house's air conditioner, which alone probably accounts for 70% of the electricity I use in the summer.

      But with no discernable feedback on how much energy it uses, no 1337 energy saving mods available, and nobody who would be impressed by those mods, the A/C unit remains out of sight, out of mind.

  • Laptop + Batteries (Score:4, Funny)

    by xee ( 128376 ) on Monday August 05, 2002 @11:00PM (#4016056) Journal
    Get a laptop and several batteries. plug the laptop in to power anywhere you can... hotels, friends houses, offices, wherever! charge up all your batteries and you're good to go. two batteries could be easily charged up throughout a day's use at the office and friend's houses. and one lasts for at least 3 hours. Weekends would be difficult, as would long programming runs.
  • I know that my computer has a 300 watt power supply, and it can barely keep the thing running. Monitor > 150 watts as well.

  • computers take very little power (Score:5, Informative)

    by Trepidity ( 597 ) <[gro.hsikcah] [ta] [todhsals-muiriled]> on Monday August 05, 2002 @11:07PM (#4016075)
    You mention 150 watts as if it's a large number.

    Some rough figures:

    Room with 3 incandescent lightbulbs: ~180 watts
    32" television: ~250 watts
    Microwave: 1000-1500 watts
    Stove: ~2000 watts
    Oven: ~3000+ watts
    Window A/C unit: 750-1250 watts
    Central A/C for a 2000 sq. foot house: ~5000 watts
    Central A/C for a 4000 sq. foot house: ~9000 watts

    So running your computer 24 hours a day would take approximately as much power as running your central A/C for maybe 20-30 mins/day. If you live in a hot climate, raising the temperature on your thermostat by 1 or 2 degrees is going to save you more power than getting rid of the computer entirely. And certainly much more than shaving 20-50 watts off your computer's power usage by using "low-power" components.
    • Nice breakdown of power usage. I checked my electrical usage at my electrical company's account webpage [kcpl.com] and it showed me a graph of my consumption, hour by hour, compared to the heat outside. They can do this, because my electrical meter has a cellular module inside.

      My average consumption was 900 watts for my 3 floor house. I use all flourescent lighting and since my basement is encased in concrete like a bomb shelter, I need little air conditioning. Most of my consumption is the refrigerator (1000 watts when on,) lights I always keep on (150 watts,) and the computers (60 watts, laptop and headless server) In fact, I run the whole house off my 600 watt inverter (sans appliances) during power outages by flipping two breakers and use my motorcycle as the generator for the marine battery. An ammeter lets me know how much I'm using around the house. I use an average of 300 watts during power outages.
    • Except for one thing: it's not 150 watts.

      My setup:

      Mitsubishi DP2040u 170 watts

      HP 1200n 285 watts while printing, 7 otherwise.

      Epson Stylus Color 3000, 21 watts.

      My computer (which caused a 300watt power supply to fail) Somewhere between 300 and 465 watts.

      Speakers, 100 watts.

      So, most of the time the system consumes about 500 watts but can peak at over 1000 watts.

      That's just one computer. I have a network laser printer for a reason...

      During the "energy crunch" here in california (assholes) I severely minimized the number of computers I had running (besides wanting to "do my part", brownouts kill computers QUIK)

      My electric bill dropped $160 before the 20/20 (20 percent off your electric bill if you use 20% less power than the same time last year.

      That means my computers together were consuming at least 1000 watts every hour, every day.

      I wish it was only 150 watts.
      • >My computer (which caused a 300watt power supply to fail) Somewhere between 300 and 465 watts

        I think that you will find your PC rarely uses peak power. When a PC POSTs it will use peak power. If you happen to be using all the devices and have the CPU at 99% you may be sitting near 300 watts. Most of the time, It will be about 150 watts.

        >Speakers, 100 watts

        Here I think you have some confusion about power sent to the speakers and power as it comes out of the wall. If your speaker system has an AC to DC converter like mine, you can read the wattage rating off that. The "100 watts x 4 channels" is refering to audio power at peak. I think the draw from the wall socket would be much lower. Maybe an audiophile can back me up/discount me on this.

        • You must have misunderstood me.

          My computer uses over 300 watts.

          0+1 raid and overclocked to 1825mhz cooling paraphenalia and a peltier.

          Let me say again, my computer uses more that 300 watts.

          I blew up a goddam 300 watt power supply.

          Did I mention that the 100 watts for speakers did not mean "I have 100 watt speakers".

          The adapter reads "Input:120vac 60hz 100w, Output 12vdc 5.2 Amp."

          Linear, not switching.

          And again, my monitor ALL BY ITSELF consumes 170 watts.

          Wait, you obviously failed to read my first post, what makes me think you'll read this one?
          • IAAEE (I am an electrical engineer) and I have been through the process of type authority approval (UL/FAA/EU/FCC etc.) and what goes into the rating plate on the back of the box it can be confusing. Different specs cause it to mean different things depending on the approving authority. For example, on radios the important safety issues is usually peak power, while on power supplies it is usually average power (too much current causes fires in the house wiring).

            The "ideal" goal of any consumer products manufacture would be to list their device as having the lowest power draw so that you can plug as many of these devices into a single wall outlet. However, there is nothing in the spec preventing a manufacture from placing a higher current DRAW on the rating plate as it does not increase the fire risk to the consumer. OTOH, they must be able to DELIVER the power output on the rating plate. Of course, the more you draw the more likely you'll shorten the life of the product ( and see higher ripple if it's a power supply).

            Now that's ideal, the truth about PC power supplies is that most of them are cheep pieces of junk. Unless you are willing to pay several hundred dollars for a 300W AT power supply do expect them to really live up to your expectations.

            So, to the point of what your system is using, on average, is probably a small fraction of what is on the rating plates. If you average is even close to half the rating plates I expect that you are going to see high failure rates on consumer products. It's just not designed for that level of average usage. The only real way to measure usage is to measure the usage with a meter. And measuring AC power usage is a whole course in school. The simple answer is to find a quality RMS logger and a good meter, at least a Fluke 83 (probably better), to measure peak usage.

    • So running your computer 24 hours a day would take approximately as much power as running your central A/C for maybe 20-30 mins/day.

      A/C certainly does use more power than a computer, and is a well-known problem. Why are there blackouts on hot days? Air conditioning. Period.

      Aside from A/C, though, none of those other items you mention would be run for anywhere near 24 hours a day. Lights don't need to be on during much of the day, or late at night. If you have kids at home for the summer, then maybe the TV runs 12 hours a day or so. But even then, 32" is huge. For comparison, my 21" TV only consumes 112W. As for those cooking appliances... I guess it depends on the meal being cooked, on the family size, etc. My oven is on approximately 30 minutes a week :)

      That's why I'm surprised you left out water heaters and refrigerators! Those suckers are on 24/7, and both use a whole lot of power.

      On a related note, I got DSL in my apartment a while ago and set up a Pentium Pro system as a web server. I turned it off about a month later when I saw my electric bill. Turning that one computer (no monitor) off cut my bill by about 40%! (Obviously, my power consumption is relatively low the rest of the time. Also, this was February/March, not the Summer. Then again, I'm in SoCal, so the weather was mild...) What this shows is that some people really could benefit from lower computer-related power consumption.
      • You don't really need to have a hot water heater on all the time. In the last place I lived where I had my own heater (as opposed to the building having an unmetered boiler) I would only turn it on in the morning, about 5-10 minutes before I had a shower. By then, it was perfectly fine. After I was done, I'd turn it off again.

        It can save quite a lot of money. Sadly, it's much harder to manage the same feat with the fridge.

    • Re:computers take very little power (Score:4, Interesting)

      by ivan256 ( 17499 ) on Tuesday August 06, 2002 @09:11AM (#4017483)
      Some rough figures:

      Some other fiures:

      Industrial sheet metal shear: 3000 watts
      Hydraulic press: 6000 watts
      Industrial arc welder: 8000 watts
      Commercial HVAC compressor (10 ton): 14,000 watts

      A small, light industrial machine shop will have multiple of each of these. There are hundreds of these shops in almost every city in the US. Residential electricity usage doesn't even begin to come close to commercial usage. Computer usage doesn't even come close to the electricity used by these big tools. The last study [lbl.gov] that was done estimated that computers are using about 2% of the power consumed nation wide. That figure included networking equipment for backbones, and other office equipment like copy machines, too!
    • In an off grid home, due to the fact the system mentioned in the article has a rating of 1.2KW, most items on your list of energy hogs are not supported.
      In an off grid situation, the stove, water heater, and central heat are not electric. Most off grid homes do have a TV and Microwave. They are simply not on for extended periods. My parents RV is designed to be "off grid" It has 800 watts of panels and a 2 kw inverter with a 60 AH battery. The fridge (7 cu ft) is an energy effecient model. None of the lighting is incandecent. The heating and cooking is all gas except for the microwave. They often will park by a favorite lake somewhere for a week and not have to run a generator. They do have a gas generator for the few dog days of summer to run the AC, but running that is rare due to the high cost of operation.
  • I know this sounds rediculously obvious (because it is), however I cannot think of any full-featured compter more efficient than a good laptop.

    You could possibly run it directly off of your DC power, and you can take it anywhere you want. Laptop power consumption is typically less than 50 watts during peak usage, and during sleep it can use much less than that.

    I know they aren't perfect, but sounds like it's what you need.

    Just my two cents.
  • It should be mentioned that off grid living is not something someone just jumps into casually. Getting your own solar plant up and running can be a bear, Theres daily managment of batterys and such. Alot of work goes into staying alive off grid.

    At present its not a big money saver. On the contrary it costs oodles more to build. With the average 3 bedroom house in nowheres ville being about 80K earthships, one form of grid house are often 350-400K in the same area. Yes I know its not the bay area of california prices but people in the bay area dont live off grid.

    As to computers there are 12 volt power supplys available. If you get rid of the inversion process (most motherboards are 12v already) you can save alot of power. Ive actually been looking at building systems and selling them that are all 12v. The other application is boats and RVs which are both fairly offgrid. I leave in about a week to spend a year in a RV so power has been a concern.

  • iMac? (Score:4, Informative)

    by Phroggy ( 441 ) <slashdot3@ p h roggy.com> on Monday August 05, 2002 @11:24PM (#4016125) Homepage
    Many of Apple's computers give off little enough heat that they do not require cooling fans, and those that do have fans still run cooler than most PCs. I would guess that this means they consume less power than most PCs (less heat coming out = less power going in, yes?). I'd also guess that the PowerPC being RISC rather than CISC helps a bit; that should mean the processor is less complicated and more efficient.

    As someone else pointed out, LCD displays consume less power than CRTs.

    Would not a G4 iMac then be perfect for this situation?
    • This just shows how ineffective Apple has been at marketing its computers and how entrenched the PC is.

      Here is a situation that seems to be custom made to bring in the iMac, and to reject power-hungry Intel/AMD chips. And yet these people put on their consumer blinders and bought a PC.

  • Micro hydroelectric (Score:2, Informative)

    by Anonymous Coward
    If you're privileged enough to have running water on your property, you can't beat micro hydroelectric.

    For $1500, you can get a 2.5kW micro hydroelectric generator. Compare that to $700 for a little 100W solar system.

    The best part is that micro hydroelectric is a 24 hour power source for 60kW/hours per day of monkey-shocking goodness.

    http://www.solarelectric.com/products/level3_43. ht m

  • Product data (Score:3, Insightful)

    by TheSHAD0W ( 258774 ) on Tuesday August 06, 2002 @12:15AM (#4016258) Homepage
    Linksys PCMCIA 10/100 ethernet card [linksys.com]

    Power:
    5V 260mA, 60mA sleep mode
    3V 180mA, 30mA sleep mode

    Linksys PCMCIA 802.11b wireless card [linksys.com]

    Power:
    5V or 3.3V
    275mA TX, 225mA RX, 20mA standby

    Or to put it simply, when operating, the wireless card operates at up to double the power requirements of the wired interface, while giving a maximum of 1/10th the speed. (That's a very optimistic maximum, as well.) There are a few added power drains for wired networks, such as powered hubs and switches, but I'd have to go with the wired net, every time.
  • This may be common geek knowledge but I didnt learn it till a few years ago. All those AC adapters you have (speakers, chargers, etc etc etc) suck up power whenever they are plugged in, even if the device they power is OFF. I always thought I was saving a majority of the energy my computer uses by turning off the monitor. Turns out that those lil bad boys just really SUCK. I am suprised that they dont have some way to well... NOT do that?
  • I'd like to know how much power my applicances are sucking up.

    He mentioned the Watts Up? Meter:
    http://www.greenculture.com/pr/es.html

    Are there any other cheaper/better ways to do it?
  • Anyone else here (besides me) live in CA? I have a question.

    Would you really consider yourselves ON THE GRID? Even if you are lucky enough not to have an outtage every couple weeks, you're still paying about three-times the price for power.

    I'm not a real wholistic guy myself. I'd be just as happy with an article comparing the COST of solar panels, power grid, gasoline and natural gas (and possibly propane) generators. I love the idea of solar panels, and hope their effeciency improves, but I'm not going to waste money on what's available now.

    If I thought I could get reliable, and cheap power, I'd personally drill a several miles-deep hole into the earth.

  • Apply media company logic to this (Score:4, Funny)

    by lpontiac ( 173839 ) on Tuesday August 06, 2002 @04:33AM (#4016734)

    Approximately 1 in 10,000 households and businesses in the US get their power from people other than their local government-approved grid. Given a population of 260 million, and assuming that one household or business exists for every 2 people, that's 13000 establishments within the US that aren't giving us money!

    Now, since if these people would probably chew through $10,000 per year in electricity. That's $130,000,000 that ends up in other people's pockets!

    The sky is falling on this industry and we need laws to prevent this!

  • get over it america.
  • Anyone know what percent of our national power is used on computers? Should we be thinking wireless on laptops?

    Huh?

    I would put in a vote for ppc notebooks, for low power. Plus, when your batteries die during the night, you'll know about it but your notebook with then keep running for 2-5 hours depending. ppc desktops are low power too. If you have to use x86, I'm sure Intel and Transmetta can help.

    No fancy directional antenna, regardless of how high the Effective Radiated Power, is going to beat the energy efficiency of a cable directed to the other end. : )

  • Solar Works Great in San Jose (Score:3, Interesting)

    by an_art ( 521552 ) on Tuesday August 06, 2002 @12:00PM (#4018628)
    Enron inspired my wife and I to have a 2.3kW grid-tied solar system installed on our San Jose,CA roof in Feb 2002. We entered a Net Metering contract with PG&E, such that we are only billed once a year, and our electric meter is a time-of-use meter that permits us to be charged less for off-peak usage. Our excess energy is fed onto the grid, thereby running our meter backwards most days during peak billing hours. Most of our consumption is off-peak, therefore we mostly sell energy at a higher billing rate than that at which we buy it back.

    We had already installed a setback thermostat, replaced incandescent bulbs with CFL's, replaced a desktop CRT with LCD display and do most food reheating in a microwave. Our desktop is a Mac G4, which uses less energy than an equivalent desktop Pentium due to the nature of the Pentium chip set, and our other computers are Mac laptops, which are very efficient. No wall warts or other gear are left on when unused in our house. [ Note also that with any type of computer gear, all else being equal, the faster the clock rate, the higher the energy consumption, and the more waste heat that has to be dissipated somehow. If you don't like throwing your money away, for any given task use the slowest "suitable" system. No one should ever need 1.4GHz clock and DDR RAM to compose a text message! ]

    The net result is that we will likely generate >100% of our electric needs in an average year, despite our electric stove, and using one or more computers and a TV or Stereo every evening. The installation has a 20 year warranty and will pay itself back in 15-20 years, unlike *any* other toy that I've ever purchased. No, it's not for everyone, and you have to take a long view to justify the expense, but it is quite practical in a reasonable climate, particularly if you have a more or less south facing roof.
    Art

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