Slashdot Mirror
Efficient Power Supply Contest
A reader writes: "In the June (paper) issue of Scientific American, there is a mini-article descibing the energy being wasted by power supplies in computers. Those things are only 60-70% efficient in converting line-voltage AC to low-voltage DC, and there are so many millions of them out there that a modest efficiency increase could trim $1billion or more from the annual energy costs of the USA. Well, various governmental agencies are seeking to get improved power-supply efficiency into the marketplace. The central "clearinghouse" site is at efficientpowersupplies.org, and details of their contest are in this PDF."
I'll give 2:1 odds its down before 10 comments are posted...
Please enjoy Google's version of the main page (efficientpowersupplies.org)
Please enjoy Google's HTML Version of the PDF.
I promise no Karma Whoring, courtesy of your (sometimes) friendly AC :)
Its a step in the right direction, alot, alot of people burn electricity like its free.
For The Best Jazz/Hip-hop fusion > COlD DUCK
You can also check out power supply reviews on Silent PC Review. They concern themselves with efficiency since an efficient power supply can be quieter and produce less heat.
The site also has a lot of other good info.
Energy costs at a company I worked for in SiValley were becoming such a factor that they dropped the use of all CRT monitors and towers in the work place. They switched us all to thinkpads. Now, on a small level this is very inefficient, but from a large perspective, I am assuming the energy cost savings would be enormous. My tower/crt costs me at least $25+ per month at home. I could easily lease a lowlevel laptop for that.
Aj
GroupShares.com A free and interactive stock market community. It is just getting started so check it out!
-------
artlu.net
you build it, they will come
Great idea! There are so many things that we keep doing in a wasteful and inelegant way just because it's "good enough" (or at least was in the past -- when things get wider distribution, problems are magnified).
Power supplies are a good example, as are cars (so much wasted energy -- hybrids are better in that regard, though, like in converting braking energy into electrical energy that can be re-used later to help the engine when it's at its most inefficient RPM levels).
Treehugger? Treehugger... Treehugger!
especially since i use several UPSes which add another layer of inefficiency.
i want an efficient AC to DC UPS which connects directly to a DC powersupply for my box(en).
that would rock.
don't get me started on an entire DC house running off of a fuel cell and/or wind/water generators. woot!
I wonder how they are going to name the eventual award statue/sculpture and what it's going to look like...
Does anyone have anything to say about the efficiency of wallwarts (those small powersupply bricks)? What about having them plugged into the wall but not plugged into any device?
Switching supplies can approach 90% efficiency if they are carefully built. Such supplies will cost more, naturally, but an improvement from 60% to 90% efficiency will save you the extra cost over the course of a year or so. And, of course, you can feel better that you are contributing slightly less to carbon dioxide emissions.
How much extra spent on power supplies? High efficiency, high-current (500W+, where PC supplies are headed) are not cheap to produce.
It would be far better if government worked to reduce the amount of petroleum being consumed through initiatives to encourage telecommuting, locating companies in locations that don't require commuting in the first place, and research into fuel cells and hybrid vehicles.
..don't panic
They keep my bedroom warm in the winter without kicking on the furnace, and the fan blowing air over them masks the street noise outside.
i have something to say on that:
"don't do it"
simple enough. they are still converting even though it's more efficient than normal since there is smaller load.
I'm not sure that cumulatively saving a billion dollars accomplishes anything.
The difference per person won't be felt.
The difference in income for the power companies might be felt.
I don't feel sorry for them, but they are a big part of our economy.
Like any other industry I would expect them to raise their price to maintain their income.
Sure, this is contrary to supply and demand but most of our economy is.
I would guess that the cheap power supplies waste more than others?
The Opportunity Power supplies are one of the crucial building blocks of a modern society, converting high-voltage alternating current (AC) into low-voltage direct current (DC) for use by the electronic circuits in office equipment, telecommunications, and consumer electronics. Over 2.5 billion AC/DC power supplies are currently in use in the United States alone. About 6 to 10 billion are in use worldwide.
While the best power supplies are more than 90% efficient, some are only 20 to 40% efficient, wasting the majority of the electricity that passes through them. As a result, today's power supplies consume at least 2% of all U.S. electricity production. More efficient power supply designs could cut that usage in half, saving nearly $3 billion and about 24 million tons of carbon dioxide emissions per year.
The Purpose of This Web Site This Web site was created by EPRI PEAC Corporation and Ecos Consulting to initiate a global dialogue about energy efficient power supplies. Our focus here is particularly on the issue of energy consumption in the active or "on" mode of product operation. According to our research so far, nearly 75% of all the energy used by power supplies occurs in active mode. For those interested primarily in standby power consumption or other low-power modes, please visit Lawrence Berkeley National Laboratory's Web site on that topic at http://standby.lbl.gov.
The California Energy Commission's PIER (Public Interest Energy Research) program has funded Ecos, EPRI PEAC, and the Energy Innovation Institute (E2I) to assess the efficiencies of modern power supplies and recommend strategies for improving them. An open exchange of design information, test methods, measured results, and other related documents is essential to that project's success, tapping the best information available from manufacturers, government agencies, utilities, and product users.
In addition, Ecos and EPRI PEAC are working on a variety of other power supply efficiency initiatives in the U.S., Europe, and Asia, described in more detail under Projects. Our goal in every case is to accelerate the market for more energy-efficient products, saving energy and preventing pollution.
How You Can Get Involved
Chaos will always win out over order because chaos is more organized
apparently computers are also a huge source of greenhouse gas. if you're feeling environmentally friendly, check this out: http://www.npr.org/features/feature.php?wfId=19604 28
-ninjaneer
WTF kind of tower/ctr are you using that uses that much power??
me thinks you dropped a couple of decimal places on that one
A great concept to inspire a broad range of entries.
LETS DECOMPOSE & ENJOY ASSEMBLING
What if the same idea where applied to computers. Right next to the standard wall outlet would be a world standardized jack with six or eight pins for each of the required voltages.
Low voltage computer mains would make UPS systems less complicated too.
I've even heard of vendors who make telco friendly rackmount PC's that take 48v DC mains.
This is a boring sig
My tower/crt costs me at least $25+ per month at home.
Jesus! I knew electricity wasn't cheap in California, but I didn't know it was THAT expensive
The power supply in my S-100 bus Z-80 computer weighed about 20 kg. Apple was one of the first microcomputer companies to use switching power supplies.
Mea navis aericumbens anguillis abundat
the processors will continue to use more power... given current technology.
so fret not thyne egg fryer for your AMD powered stovetop shall still run hot!
http://www.mini-box.com
You should look into telco equipment then, I understand they do a lot of stuff with 48VDC.
7 November 2006: The day Americans realized corruption and incompetence weren't addressing 11 September 2001
Why cast the argument in such statist terms: "trim $1billion or more from the annual energy costs of the USA"?
Nobody except liberals consider 'the annual energy costs of the USA'. People do (and should) consider THEIR annual energy costs. The fact that this decreases the amount of money spent in the USA is a secondary benefit, directly derived from the primary, i.e. the reduction in cost to the individual. The USA is not the Borg, and no country should be. Treating the entire country as one entity is the first step on a long, dark road.
I want to delete my account but Slashdot doesn't allow it.
by switching from energy guzzling CRTs to cool power efficient flat screens. I went from a 19" CRT at 350w to a 19" flat screen at 50w quite painlessly.
I doubt you could achieve that kind of savings no matter how power efficient you made the PS.
Reminds me of the one about the Canadian Government buildings being determined to cost $200 a year per sq ft to maintain, so they replaced the CRTs with LCDs because they used less space, and therefore would cost less to maintain.
*sigh*
If you could be told what you can see or read, then it follows that you could be told what to say or think - BoC
I am definatly interested in more efficient power suplies, as well as more efficient processors. I have just recently built an arcade system dedicated to the game NeverBall and NeverPutt which uses a 7" LCD and a Trackball for input. The PC sits under the bar and idles most of the day. The 600MHz Celeron CPU uses little power, and I'm sure a Transmeta or Via C3 would use even less but its what I had. My main concern with leaving the box on all of the time is the power drain. Already with a MythPC and a Squid box running all the time my powerbill is in the 100-150 range for a guy a cat and an apartment.
/. which showed what the average powersuply costs in $/mo but I cant seem to find it right now. I use a power brick for my laptop and see similar products for sale for Mini-ITX PC's. Is there a way to use these for an ATX and are they more efficient than normal PSU?
The PSU in the NeverBall-Box is a 250Watt ATX from Compusa (not sure who makes compusa brand PSU). I once ran across a link on
PS: OT: Anyone else have issues with neverball and ATI? Got texture probs with Rage and Radeon on XP. Sorry so off topic.
Im dreaming ofa big bndwdth, That can resist the
In short, there is almost NO reason to not use those fluorescent bulbs and it would result in a far greater amount of energy savings right now...
Every electronic doodad I can think of has an AC/DC adapter. It's not just an issue with computers.
And it would be nice to get rid of those bulky AC/DC power bricks too...
Carl
Vote Libertarian
link no workie,
can't find references to the article
I make up for the lost 35% by not running my heat as much.
[wallwarts with the load unplugged] are still converting even though it's more efficient than normal since there is smaller load.
Actually, they're LESS efficient than normal. With no load, ALL the power they consume is wasted - efficience is 0%. B-)
Now the total AMOUNT of waste IS typically lower. But it's not trivial. Even the lowest tech wallwart burns power heating copper in the transformer and making up leakage in the capacitors. If it has a switching regulator it's also burning a bunch of power keeping that alive. And a voltage-flattening/capacitor-discharging resistor actually INCREASES the amount of power wasted in the wart when the load is gone (by eating some of the power that WOULD have gone into the load).
So why waste ANY by leaving the wart plugged in?
You can guesstimate the power by feeling the wart when it's been sitting there with no load for a while. The hotter, the more waste.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
If you're not drawing any current, you're not using any power.
Now there are losses in just having them plugged in as they usually have some form of circutry in there, but these are pretty minor. Nevertheless, if you want to be truly energy efficent, unplug them from the wall.
I really wish there were a standard 5V/12V DC interface for home/office use. If you want 60 Hz 120V AC (or 50Hz 220V AC for much of the world) you plug in your device into a standard power connector (ignorning the us, uk, and european connector divergance). Anyway, if you are like me, you probably have about 20 little wall warts (smallish DC power transformers) plugged in under your desk. Wouldn't it be wonderful if there were an ANSI/ISO standard 5V/12V DC power bus that all these devices could plug into? Imagine the joy of not having 20 wall warts plugged into 4 power strips under your desk!
-Erik -- --This message was written using 73% post-consumer electrons--
'$1billion or more from the annual energy costs of the USA'
Woah, that's like three whole dollars per person per year. Now it will only take me three years to save up to see that one extra movie. Yes!!
I remember measuring the power factor of various serverers that we were evaluating at come point, and discovering that it will vary greatly between cheap and expensive servers. Some of the cheapo ones had a pf of .4, while high-end Intel server have a pf above .9. The interesting thing is that most people (even and especially those that sell and service computer hardware) don't even know what pf is and why it is important (unless they are electrical engineers or have been directly involved in building large computing facilities where it directly impacts the cost of the electrical infrastructure).
I'm a professional engineer, and have done several designs of switchers that were better than 95% efficient. But they cost more to make, so dream on, it's not going to happen in the mainstream with out some sort of mandate. The tricks are simple, better inductors (cost more for bigger copper and more ferrite), synchronous rectification (fet and drive costs more than a diode), taking care to be clever about quiescent currents (more engineering time) and so forth.
Doug Coulter, owner
C-Lab
http://clab.mystarband.net
Because it is convenient to speak of things in their global impact. Not becuase you want to pick on liberals. You're digging kind of deep.
-- Having a Creationist Museum is like having an Atheist place of worship
Switching supplies can approach 90% efficiency if they are carefully built.
A downside of high efficiency is that the energy lost to heating is a tiny fraction of the energy handled. When certain components start to fail they can increase their losses - and this increases the heating. The higher the overall efficiency, the greater the extra heating is as a percentage of the NORMAL heating.
If this is not taken into account in the design of the supply (and its cooling budget), the supply may be prone to thermal runaway and catastrophic failures as components age.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
it's a law.
shutup. way to take a simple comment WAY to far. would it mean more to say "it'll save you $2.39/yr" or "it'll save the country a few billion?" they're just trying to show some scope here.
ugh. politics-obsessed trolls.
sweet, i can run a CoCot at my house. ;-p
...
looks like 48VDC maybe a new standard? aren't cars moving toward 48v? or was that 42? no, that's life the universe and
i was prolly going to use 12v because the wind turbine i'm planning uses used car alternators. although i could put them in series to get 48V. sweet...
All the 'inefficiency' in your computer gets emitted as heat, noise, RF or light.
Ultimately, most of the non-heat forms of energy loss get turned into heat in the surroundings when they get absorbed by something, like a wall.
So if you are trying to maintain your house at a higher temperature than it is outside, then all the lost energy from your computer goes to do useful work heating your surroundings. Hence a 100% power efficient computer.
Now if we could efficiently generate electricity, we might have an efficient total system. I don't see that happening soon.
Evil people are out to get you.
150W I could understand, but 350W! Yikes. What type of Orwellian Nightmare CRT was this?
... or about 18 in terms of electricity.
I went from a 100W-150W 19" CRT to a 50W-80W TFT monitor (not that I've measured actual power usage at the plug socket for either). Considering that I use the computer 10 hours a day, 300 days a year, that is a saving of 180kW a year
The official model of the US, put in place by the Founding Fathers, is "E Pluribus Unum" or "Out of many, one". The founders did not share the philosophical view of Ayn Rand, and creating a state was exactly what they were committed to.
Besides, energy efficiency is a national security interest. Over-dependence on oil imports means the US is more likely to engage in foreign wars.
Power company exec 1.
As you can see gentlemen, with all these efficient switching power supplys RIPPING us off, we have to do something to stop this silly efficiency craze. Its costing us a billion dollars a year!
Power company exec 2.
Well, we could always raise the rates we charge, or bury some "switching supply" tax in the customers bill every month.
Power company exec 1. Dude! You're a genius!
"I bow to no man" - Riddick
Isn't it just the transformer that makes the power supply ineffeicent (and also heavy)?
I've never understood why they don't just bridge-rectify mains to get DC, then feed the result ( via a suitable resistor and smoothing capacitor ) straight into some voltage regulators . Obviously the marketable version would require some safety mechanisms.
Can someone with more electronics knowledge than me (which is probably just about everyone) explain what the problem is with this approach?
Wouldn't it also approach 100% efficiency, assuming the voltage regulators were reasonably efficient?
but not connected to its device, the circuit is not complete and thus the PS is not drawing any power. (IANAEE but think I'm on reasonably solid ground here.)
Heh - 'ground'. I kill me.
When the PS and device are connected and plugged in, I think the efficiency depends on the quality and design of the PS. I've noticed the inexpensive 'universal' models seem to get warm, but the one for my Sony Clie does not. Better design (re: heat transfer)? Better quality? I'm guessing a little from column A and a little from column B.
PS Yes, I'm using PS and charger interchangebly to some extent, but that's the context in which I normally see these 'wallwarts'.
I want to drag this out as long as possible. Bring me my protractor.
i want an efficient AC to DC UPS which connects directly to a DC powersupply for my box(en).
that would rock.
I too have thought about this recently, and yes it would rock. It would remove the heat from the power supply from being inside of the case of the computer, make the computer case smaller, and it would really rock in the sense of high density rackmount installations.
The efficiency of coal-burning plants, generators, etc. is probably considerably worse.
Some large buildings have very large flouresent ballasts in the basement (or where-ever) because they can more effectively provide that power as a large unit rather than hundreds of small units.
What if the same idea where applied to computers. Right next to the standard wall outlet would be a world standardized jack with six or eight pins for each of the required voltages.
Computer supply voltages are VERY LOW - and trending lower. That means, for a given amount of power, their currents are VERY HIGH. Losses in wiring (for a given size of wire) go up with the SQUARE of the current.
The result is that you'd need to wire such outlets with fat copper bars, rather than "wire", to avoid losing far more in the wiring than you'd gain in the improved power supply in the basement.
Computer requirements (especially voltages) are rapidly changing, the voltages have to be well regulated (meaning you need regulation after the outlet anyhow), and a lose connection interrupting one of the set of voltages can be big trouble. So you're stuck with power supplies in the box.
(Indeed, makers of some high-reliability networking devices, including the company where I work, put a set of power supplies on EACH CARD, rather than depending on a redundant pair in the box to power all the cards.)
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
Last night, while I was out watching my power meter spin and spin and spin... It got me thinking about a digital whole house power meter that I could monitor. I want to be able to get a true RMS power meter that can measure 100+ amps AC, and outputs the data somehow. I'll write a little app to track and graph it, and work on lowering my overall house power usage.
:)
Todd
Anyone know of such a device? There are industrial ones out there, but I haven't seen a reasonable priced one for household use.
Hey, I am an electrical engineer; maybe I should just make one.
Think about the number of devices in your home that use some form of transformer to operate - Odds are it's MOST of them. With the exception of appliances, most things run on DC and require a transformer/power supply to operate. While we are at building this efficient power supply - why not make it one big efficient supply that goes in the basement of your home, with 12v 9v and 5v lines running throughout the house, instead of the 120v lines we currently have. Imagine the savings when a device no longer has to come with a special power supply, you just plug it into the 12v socket. Wire gauges inside your houses walls could be smaller and safer, with only the larger wires being run to certain devices. Even lighting could run on 12v instead of 120, likely at an energy savings........
Don't Tread on Me
whoa, wait a minute. Most UPS's connect you directly to the AC lines. They only switch on to the DC-to-AC circuit when power is lost.
No inefficiency there buddy. Most of the time you're just connected to the AC lines like normal.
Last summer, when I was wiring my newly acquired house with Cat-5, I had a very similar idea: in addition to the standard AC line, you could add even just a single Cat-5 strand with phone, ethernet, and DC power. You would then install a single common power supply in the wall, somewhere, hooked to both 4AC and DC lines. You could even have multiple power supplies, depending on your needs -- one per room, floor, building, etc. Aside from being much more efficient, this would also do away with "wall-warts" once and for all (yay!), replaced with small inline voltage regulators or DC-DC converters.
...
You could also make the outlets themselves more intelligent by hooking them to the ethernet (perhaps with little 4-port hubs in each outlet), and have the outlet itself be able to control voltage output (a la X10). For extra spiffiness, you could include a per-outlet digital ammetter to keep track of the power consumption of every device and appliance. With this in place, you could also have a house-wide UPS, such that when the power went out, the master controller would tell the outlets to shut off high-drain devices to conserve power for the important stuff.
Of course, all this might make the outlets a tiny bit more expensive
Ha, I was just going to say the same thing.
Like the supplies they use in satelites are way more efficient than 95% even.
Watt's law - P=VI = V2/R - double the voltage and you can get 1/4 times the power loss over the same wires .... the really low voltages (high current) used by PCs would require huge copper bus bars through the building
I've seen one model of PS out there with no moving parts (ie. no fans). They claim that it's also more efficient (it woudl have to be because if it releases a lot of heat, it would need a fan, etc). Is it theoretically possible to take all of the components of a working PS and spread them out throughout the entire case? This would A) increase the airflow around all of the heat producing components and B) make way for interesting case mods/new form factors. The downsides that I can see are the loss in voltage over the increased wire lengths and idiots who don't know what they're doing zap the sh** out of themselves by touching the wrong thing. Does anyone think that this has potential or is it just a great way to kill off... er, teach some not-so-bright people about what 120VAC can do to your extremities?
"The object of war is not to die for your country, but to make the other bastard die for his." - Patton
errrmm.. I think the wire guages might actually get larger....
If you decrease the volts by a factor of say 10 to go from 120 to 12v, you'll need a 10x increase in Amps (current) to get the same amount of energy (watts).
"i want an efficient AC to DC UPS which connects directly to a DC powersupply for my box(en).
that would rock."
It exists. The only useful feature of a laptop computer (apart from being able to play Myth2 on the train) is that it's got a built-in UPS with hours of battery backup.
Ignore the crappy small screen that's too low to see, ignore the crappy keyboard that's too small to type, and ignore the crappy touchpad that makes you think it would be easier to control the cursor by blowing on a straw. Just plug in your big monitor, your proper keyboard, and your optical mouse, close the lid, and it becomes a proper computer again, which will carry on working even after your power company's totally capable 60-year-old equipment takes a short nap and redirects your power to Oklahoma.
And if you've got enough laptops in the area, the wireless mesh network might even survive cuts in the telephone system. If only we could create a mesh network without getting spam sent 'from' our connection...
In other words, efficiency can save your ears and lower your stress level too.
Lacking <sarcasm> tags,
But you wont need as many amps to run most devices - yes appliances will still require larger 120v lines like we already have, but things like your cell phone charger, a small 12v lamp, your electric shaver, etc - require very little amperage.
Don't Tread on Me
Out of many (states), one (nation). Basically this statement refers to the representative government (republic) that was established, not a pure democracy.
It has nothing to do with the role of the citizen, let alone imply any obligation of citizens to a collective.
Though we do agree that energy efficiency is indeed a national security issue.
"Ask not what your country can do for you." --John F. Kennedy
You would STILL need heavy busbars with 12VAC, for the same reason you would need them with low voltage DC--VOLTAGE DROP. To transfer a given amount of power at low voltage, the current must be correspondingly higher. High currents cause excessive voltage drops at connections and in conductors. Wire sizes become impractical, both from a physical as well as a cost standpoint (copper costs money!). The 120 VAC standard is a good compromise between required current and voltage hazard.
Remember "News for Nerds, Stuff that Matters"? Help make it a reality again! http://soylentnews.org
... but what about stuff like my l33t gamerz PC with the newest amp-guzzling NVidia 6800 video card? (I read somewhere it requires a minimum of a 550 Watt PSU in the PC).
There are so many devices requiring low voltage that governments should start considering a new standard. Along the 120V/220V wall outlet, a little 12V wall outlet should become standard. This way, we would not have to provide a transformer for the telephone, the battery charger, the portable vacum cleaner, the portable CD writer, kitchen counter lighting, etc...
Obviously, retrofiting old houses is out of the question, except when major renovation. But it should be introduced for new houses. Thus, you would buy your equipment and transformer separatly, and those who already have 12V wall outlet would not need to buy the transformers.
Remember the year 2000? They promised us flying cars. They delivered the PT Cruiser...
That's not a totally inane rational.
Each worker needs a minimum amount of space to get their work done. My two old CRTs took up my entire desk, requiring me to have another desk in order to do any work that required paper. The new LCDs have freed enough space on my desk that I can use it for both purposes. This would allow them to mandate removal of my other desk and reduction in size of my cubbyhole.
If everyone's space needs can be reduced by a few square feet, we can pack in more people without the current occupants feeling more squished. Alternatively, we can improve the working environment for cramped people without actually investing in new office space.
Thus if I save 2 square feet at $200 per foot, I can actually justify spending $400 on a new monitor. I can spend more on monitors for workers in space limited work areas.
This is not a political statement. This is not legal advice. It's a frick'n Slasdot post. However: I'm Running For
is to NOT convert from the AC power at all.
I have several mini-ITX boards with a 12Volt to ATX power supply on them that has a much higher efficency rating.
coupled with the fact that the mini ITX board does everything a larger computer that uses 4X the power, I'd think the power supply is not the only place to look for efficiency gains.
I built a wifi/data server for my Motorhome from a K7SOM+ motherboard with a 1.2ghz duron on it. It uses, with all the other parts and drives, almost 150 watts of power. the SAME setup with a miniITX motherboard uses 45 watts and runs non stop for weeks on the batteries+solar panel I have on the motorhome. I do not see a drop in my battery voltage or storage from leaving it running along with it's wifi gear. (I have 4 batteries in the RV with 1 100 watt solar charging panel.)
and the mini-ITX board is just as fast and capable as the other board, plus would be plenty of machine for almost 70% of the computer users on this planet (ok no gamers)
Do not look at laser with remaining good eye.
One thing that comes to mind is that computer produced heat is not always a problem.
In many parts of USA you have to cool the area where computers are located with AC. That means, if the computer consumes 1kW you might end up with a total energy cost of 3-4 kW.
In colder parts of the world the equation is fairly different. In a room that is heated anyway (often from electricity) leaving computers or lights on cost absolutely nothing - its just a way of using the energy twice. Both a radiator and a computer end up being 100% efficient when it comes to producing heat.
You can save far more energy by shutting them off, as in disconnecting the power going to them. Energy saving devices don't save energy any more than screen savers save screens.
"I may be synthetic, but I'm not stupid." -- Bishop 341-B
It's called a "marine battery." You ditch the internal power supply and feed DC from an external battery (through a voltage regulator) directly to the motherboard. I essence you've now turned your desktop into a descrete componant laptop (for sufficiently large values of "lap"). It's really not that hard.
Now, since you're never running on anything but battery power, you don't need most of the functionality of the common UPS. Your computer's own power managment takes care of all that.
And the beauty of it is exactly where you say it is, you can now draw your energy from any source that can produce electricity. That could be a battery charger plugged into your wall socket, or it could be a solar panel sitting on your cabin top, a small wind turbine sitting on your taffrail, a water turbine being dragged behind, a hand cranked/pedal powered generator, or even, yes, hamsters.
It's completely source agnostic upstream from the battery.
Your case is also smaller and cooler, but your "UPS" is no bigger or heavier if you already use an "enterprise class" (warp overclocking Mr. Sulu!) UPS.
Frankly, so far as I can tell, the only reason we do it the way we typically do it (if you're not a boater or RVer) is because we've always done it that way. We've declined to reinvent the wheel when such might actually be appropriate, chosing instead to add wheels to the existing wheels in extending chains of Rube Goldbergesque functionality.
KFG
It seems that with average driving they aren't quite what you'd expect. The published mileage figures aren't for real world conditions. My properly maintained and driven 2000 Chevy Lumina company car with 92,000 miles gets 26 MPG with a combination of highway and city driving.
Read this Wired's story
"Do the Right Thing. It will gratify some people and astound the rest." - Mark Twain
"Do the Right Thing. It will gratify some people and astound the rest." - Mark Twain
You are absolutely correct with that assessment that 90% efficiency is attainable for all the reasons stated and beyond actually. 97% is attainable in switching power supplies at higher power levels. But the rub is in the increased cost of manufacture and the corrosponding cost increase to the end user versus the payback in energy cost savings over time. Could billions of energy dollars be conserved via increases in efficiency? Not if it costs billions to achieve it and at that, to increase efficiency in one part of a system that gets blown away in others is questionable. I'm thinking of those brute force voltage regulators on the motherboard when I say that. The ones that will burn your finger after a few minutes of run time. Sure, savings is savings and I understand that but without a return on investment there is little point.
For those who seriously want to save a bunch of hydrocarbon from going up the stack, the answer remains as clear today as it was yesterday. Build Nuke plants. You can't conserve your way to prosperity.
Many devices have the wallwart seperate from the actual device, many do not, but this is at least a partial solution. If the power supply is seperate it will probably have the volt/amperage ratings on it. You can use that to build your own super efficient power supply that connects with the standard connectors they use.
I did this myself to power a bunch of guitar pedals, it was cheaper to build my own power supply than to either buy a bunch of small ones, buy a pre-built one (everything for guitar equipment is overpriced), or just keep using batteries for them.
Of course I never checked for efficiency, I just knew it was cheaper to build.
Photos.
The AC that comes into your power supply is first rectified into 300 volt DC.
Note the diode bridge and big capacitors inside. (for those of you looking, DO NOT TOUCH anything because the capacitors may still be charged even after the supply is off and unplugged)
The most efficient UPS would be 300 Volts of batteries connected to the DC bus in the power supply itself.
Using 12 volt (nominal) car batteries you would need 300/12 = 25 batteries in series to provide 300 Volts.
Upside: at $35 per battery, you would have a reeeeeeaaallllyyyy long backup time for $875.
Downside:
You probably need to make chargers that charge each battery individually to avoid imbalance in the cells.
At a weight of about 40 lbs per battery, (total = 1000 lb) you probably want to keep the batteries in the cellar.(although battries will last a lot longer at lower ambient temperatures.)
So - go live in your car, it has a 13.5 volt power supply. Oh, you already live there?
I would think that your best bet for making one from scratch would be to imitate one of those clamp-style ammeters and clamp it around the mains leading into your box, then measuring the current indirectly by measuring the magnetic field strength & inducted current in the clamp.
You'd probably have to compare with the meter to calibrate it, since there would be a few unknowns (e.g. if your mains are surrounded by conduit what the magnetic constants are on the conduit), but you could probably get within +/-10% by the time you were done..
yes you would. To get go from 120V to 12V and do the same amount of work you need 10X the current.
You would STILL need heavy busbars with 12VAC, for the same reason you would need them with low voltage DC--VOLTAGE DROP.
Also: Heating. It's the CURRENT that heats the wire. The limit on wire size in a wall is keeping the heat down enough that it doesn't set the walls on fire.
Your house is wired with #14 for 15A circuits, #12 for 20A, #10 for 30A.
At 120 volts a puny 15 amp circuit can provide 1650 watts, enough to run a space heater with leftovers for a couple 75 watt bulbs, or all the lights in several rooms. 20A will feed several motorized appliances or your whole computer room. A dual 30A feed easily handles an electric stove and oven, or an electric drier.
At 12 volts a 20A feed would be maxed out by four 60 watt desk lamps or a couple 100 watt ceiling lamps. (Forget the toaster.)
Yes, you'd need bussbar. Every 12V circuit would require TEN TIMES the amount of copper as a 120V circuit to provide the same amount of energy with the same percentage of it heating the walls.
That goes for the line cords, too.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
OK, that takes care of the 12V supply, that at most is used to spin things.
The motherboard also gets +5V and +3.3V, and IIRC it may also get -5V and/or -12V. Those don't come from a marine battery, without some sort of extra regulator. They'd better be buck regulators, or some other sort of switching regulators, or your efficiency's shot, again.
Next problem, droop, especially on the lower voltage supplies. I don't know how close you were planning on having the marine battery to the motherboard, or what size copper wires you were planning on using, but supply feed resistance can be an issue. As components get to lower and lower voltages, the supply tolerance tightens. (millivolt-wise it's getting smaller, the percentage is staying pretty close to the same.) This is normally solved with regulation and Kelvin sensing.
Oh, you also can't use marine batteries unless you've also planned ventilation. They can give of hydrogen gas when being charged. UPS batteries are sealed for this reason.
Not that there isn't merit to your thought, it's just that a little more thought is needed before it becomes practical.
The living have better things to do than to continue hating the dead.
Of course you loose a lot of efficency gains right at the voltage regulator. If you really want to do this right you need a DC-DC converter (generally fairly expensive, but often 98%+ efficent).
I read the internet for the articles.
You could put all the computers in the room with the big power supply, and either use thin clients or possibly run DVI + USB cables up to the worker's desks.
Dodges the resistive losses nicely, though it has other problems.
The 300V is because that's what you get when you rectify line voltage, depending on the style of rectifier you use, and if you want to have the simple 120/240V operation in one box.
The fact of the matter is, we're talking about switching regulators, here. They can take practically any DC voltage and turn it into practically any other DC voltage. If you're designing from scratch, the obvious thing to do would be to pick a well-suited battery and design from there.
The living have better things to do than to continue hating the dead.
Bring the USA into line with the rest of the world and use 230VAC instead of 110V. This halves the current through the wiring, thus halving the power wasted. And cables need only half the copper for the lower current, saving raw materials into the bargain.
Here is one example of a DC-input ATX power supply. It uses 24V in, so it's up to you how you want to mix'n'match utility AC and alternate DC sources. For more general info along those lines, check out Home Power.
--The more you know, the less you know.
No, your question and your understanding was valid. The power rating on a power supply states what maximum power the supply can deliver to its load. The actual power consumed *from* the power supply is solely a function of the load attached to it (i.e. the "computer" components it runs). The actual power consumed *from* the wall outlet is the sum of the power consumed by the power supply's load (i.e. the computer components) plus the extra power consumed by the power supply (i.e. the waste) which is directly proportional to the power supply's efficiency.
WarriorPoet42 got it right the second time around - but this did not make your question "stupid."
BY THE WAY: Just because you have a 400W power supply in your PC does NOT mean you are consuming 400W of power from the AC outlet. If you put an older (slower) CPU/mobo with no expansion cards, and run, say, a modern low-power hard drive, etc., the LOAD presented to the 400W power supply will be much lower. Think about it. Small form factor PCs are often built with 150W power supplies. This means that the components NEVER consume more than 150W, and probably seldom if ever hit that peak.
A side-effect of this is that the power supply efficiency does not necessarily always *waste* its ratedpower-minus-(1-minus-efficiency).
(whaatt??) Let's say:
R is the power supply's rated power.
E is its efficiency expressed as a fraction of 1 (i.e. 90% efficiency is expressed as 0.9)
So, a 400W (R=400) power supply with 80% (E=0.8) efficiency will *waste* 400*(1.0 - 0.8) 80 watts of power. But ONLY if the LOAD is drawing the full 400 watts of power!
Now let's say we have a 400W power supply with 80% efficiency, but the computer components only draw 180W of power. Let's use C to represent the power draw of the computer, so C=180. Now, just substitute C for R and you get:
C*(1-E) = 180*(1.0 - 0.8) = 36W. This is what you are REALLY losing due to power supply inefficiency.
Note: A switching power supply will have some minimal losses even if there is NO load attached to it. These are small compared to the efficiency losses in normal operation, so for practical purposes may be ignored. You could add a constant (say, K) to the equations above to account for this static power loss in the power supply, but K would be small, when compared to C, so has little effect on the math....
Well, 240V root-mean-square, 377V peak (in the US). Keep in mind that if you're only chewing off the tops of the peaks, your equipment will have a poor power factor.
Using 12 volt (nominal) car batteries you would need 300/12 = 25 batteries in series to provide 300 Volts.
Don't use car batteries. They're very cheap per amp-hour but they'll be ruined by deep discharges. Use deep cycle marine batteries or sealed lead acid cells. SLA's are available in just about any size desired.
you probably want to keep the batteries in the cellar.
Charging lead-acid cells releases hydrogen. Make damn sure the hydrogen can be vented outside instead of building up and possibly causing an explosion. And put the whole thing in a container that can safely contain sulfuric acid.
This isn't turning things off at random. This is scientific method. Hypothesis, experiment, etc. Global warming melts ice caps. Ice caps raise sea level, affect the weather, etc. This isn't guessing. You are basically saying
"lets blow up a big nuclear bomb somewhere. If it's close to us, we are fucked, if it's far away from us, maybe some asshole will die and we are better off for it"
-- Having a Creationist Museum is like having an Atheist place of worship
Remember the primary reason for shipping around (transmission) power using AC is the EASE (simplicity, cost) of using stepdown transformers to change the V*I mix and resultant voltage, it is really power to impedence matching. So unless you have MANY devices that will NATIVELY use a common low voltage DC level, e.g. 12V, you haven't gained anything, in fact you are probably contributing to more power waste (i.e. poor impedence matching). When I say "natively" use 12V, this means that the core circuit really wants 12V. If you are thinking, well, 5V is less than 12V, so that should work too, NO... What are you going to do with that extra 7V ? Well, unless you are into countless DC-DC converters for every single device, you are going to WASTE that 7V x current == POWER in the form of heat. You are much better off using the 120VAC->7V stepdown transformer -- less wasted power). Then you have devices like a common stereo or fluorescent backlighting for LCD displays. These devices REQUIRE much higher voltages, from 30-100V (12V through 8ohm speakers just isn't enough audio power). There just isn't enough commonality in DC power requires to establish a common supply that would make sure, nevermind the fat cables that would be required to carry the current (low voltage, same power, higher currents).
It sounds good to me. What's the downfall?
The man who trades freedom for security does not deserve nor will he ever receive either. - Benjamin Franklin
Seasonic Super series power supplies. My UPS load meter registered a ~15% drop in PC power consumption after I switched to these from Antec. Highly, highly recommended.
/sys/devices/systsem/cpu/cpu0/cpufreq/scaling_sets peed to match the power/performence balance you think is best. See the Athlon 64 Processor Power and Thermal Data Sheet. For example, a current top-of-the-line Athlon 64 3800+ burns 89W at 1.5V at maximum (better than Intel, but still a lot). If you lower the clock speed by 200MHz, the chip burns 72W @ 1.4V, another 200MHz lower burns 53W @ 1.3V, and another 200MHz lower burns 39W @ 1.2V. You can cut it all the way back to 22W max, 1000MHz @ 1.1V. With the current Fedora Core 2 kernel and a power management daemon like powernowd the speed will be adjusted automagically, but if you want to run Folding @ Home without excessively spiking your electric bill it's nice to set a fixed speed manually.
Also, use AMD 64-bit CPUs and set
The Mobile Athlon 64 3200+ (62W @ 1.4V max) is interesting if you really want to limit power consumption. I put one in my ASUS K8V Deluxe motherboard (Zalman CNPS7000A-AlCu heatsink, be VERY careful not to overtighten it and crack the unprotected core as there's no protective aluminum lid like on the desktop CPUs, not all heatsinks will fit). Drop 200MHz and get 46W, another 200MHz gets 34W, and at 800MHz a mere 13W. Given that the new Prescott-core Pentium 4's burns well north of 100W, this is pretty neat. Note that since AMD's transistors have a MUCH lower leakage level than Intel's (20% versus 50%) your idle power consumption at any clock rate is going to be pretty low. Things will get even better when the new 90nm chips come out in a few months.
This means what I think it does. We need to convert away from AC to DC power! Companies would save billions because almost all our devices would be simplier to design and build. As I understand it, it is alot simpler to convert DC to DC than AC to DC or DC to AC.
Here is the question. What applications require AC and would be use more power than DC?
fuel efficient cars? We haven't come all that far from the late '70's so excuse me if I am pessimistic. Wouldn't more energy be saved if people turned their computers off when they are not using them?
Sending low voltages (5 volts, etc) doesn't work. You end up with voltage drops in the wiring. Electronics that run from a specific voltage (such as 5 volts) typically need a well regulated voltage source - say, within 5%. As devices are connected and disconnect from the proposed low voltage power system, the actual observed voltage will be all over the place. Again, voltage drop in the wiring exacerbated by large loads along the line.
This is, essentially, why the original Edison DC power system was replaced by the Tesla AC system: with the DC system the guy at the end of the line ended up with dim light bulbs. (No good.) The way to combat voltage drop is to crank up the voltage on the transmission line (such that a relatively small current can carry the same amount of power) then step the voltage back down before it enters the home (for safety reasons.) In the AC power system this stepping up and down is done with transformers.
Today, you could build a DC power distribution system using switching regulators to step the voltage up and down. This technology did not exist in the Edison/Tesla days. Also, the AC system is (relatively) simple in its use of transformers where a hypothetical DC system would be (relatively) complex due to its use of active electronic circuits in the switching converters.
What could be done "in the home" is a conversion from AC to 48 volts DC. High power appliances would run on AC where lower power consumer electronics would run on 48 volts DC. This is, essentially, how the traditional (analog) phone system works as well as the new "power over Ethernet" systems.
This all gets pretty messy because now you need two types of outlets: one for high powered appliances (like a hair dryer or toaster) and a different style of outlet for consumer electronics.
Just for grins, let's take a typical LCD monitor with an external DC supply. The Monitor is 60 watts and uses 12 volts. In DC Amps X Volts = Watts. To run the monitor, it needs 12V X 5A = 60 Watts. If you simply used a resistor to drop 120 volts to 12 volts, the series current would still be 5 Amps. (the current is the same in all parts of a series circuit) 120 Volts at 5 amps is 600 Watts. You would be tossing out 600-60 = 540 Watts out as heat in that resistor.
On the other hand a power supply changes the voltage and the amps. The power supply for the monitor would draw 0.5 Amps to provide 5 amps at 12 volts for 60 watts in and 60 watts out if it was 100% effecient. It is not 100% effecient, so you may notice the supply draws 75 watts instead of 60 watts. Tossing 15 watts out as heat is a lot more effecient than tossing out 540 watts as heat. That is why power supplies are not simply a resistor, diode and capacitor.
The truth shall set you free!
I was on a quest to quiet down the PCs I've got, and came across the Seasonic Super Tornado Review over at SilentPCReview.
.98 to .99. I used a Kill-A-Watt meter to measure before/after power draw and PF. The PSUs replaced were 2 generic PSUs and one Antec True Power unit.
I measured the before and after current draw of my PCs and found that the Seasonic Super Tornado PSUs were not only much quieter than the PSUs I replaced, but also reduced current draw out of the wall about 15%. Additionally, they have a PF that I measured at
The Seasonic PSUs are the most efficient that SilentPCReview has reviewed at about 80%. It makes sense that if you are building a new PC or need to replace a failed unit to spend the money on the Seasonic units. They are even competitively priced compared to other name brand PSUs as well.
Most of the time you're just connected to the AC lines like normal.
...which is exactly what he wants to avoid. Power supplies are inefficient, remember?
1st stop would be at an electrical supply house. You want two things right off the bat. One is current transformers. They take the high current of the mains and using a turns ratio, cut it down to something that won't fry your metering. I would recommend a copuple 1000:1 for a good start. (Don't install the current transformer yourself! Use an electrician. Messing with the line from the meter before any circuit breakers is a Darwin Award canidate activity.)A fully loaded 200 amp home panel would give a much easer to meter 200 mA representing the draw. The wires for 200 mA is much easier to work with than wires for 200 amps. Next would be a potential transformer. That knocks the 120/240 volts down to about 12/24 volts depending on the ratio transformer you choose. From there that can be fed into a true RMS wattmeter interface. Beyond that, find your favorite graphing/logging software.
A great place to look for these items and monitoring software is on the web. Look up suppliers of co-generation supplies. Those who generate their own have created a market in monitoring and metering for the small guy.
The truth shall set you free!
With modern semiconductors (such as power mosfests used as synchronous rectifiers) it's easy enough to make a more efficient supply, but of course the parts are more expensive. Power supply makers want to make the cheapest things that pass UL/CSA/whatever standards (or go even cheapers and not even bother with safety standards).
And from a buyer standpoint, it may or may not make economic sense to have more efficient power supplies. If using ten dollars more in parts makes a computer that usees one dollar less electricity per year, then why would anyone buy it, other than government regulations require it to be made that way?
Highly efficient switching supplies are indeed being made - these are often DC-to-DC converters for for internal use in various products. I've seen a device that takes 15 to 30VDC and outputs 5V at 20A (that's 100 watts, enough for a really hot light bulb), and it's the size of a book of matches (this was six years ago, I'm sure things are even better now). It has to be 95 percent efficient just so it can be made so small without burning up from its own waste heat.
A more substantial savings in electric power consumption can be made by replacing CRT monitors with the latest thin/flat monitors (using TFT/liquid crystal/whatever-it-is technology). I'll be the first in line to trade in my 17" and 21" CRT monitors for lower-power current-technology replacements if someone (The Government, for example) wants to pay for it.
I don't know what the real agenda might be of the entitiy that came up with this idea, but if they really want to reduce overall power consumtion, they can surely find other things with better cost/benefit ratios.
Tag lost or not installed.
Your electric meter tells how many kilowatt hours you consume. The same meter with the help of a clock that measures seconds and some simple math can show you how many watts your appliances use. The disk that rotates in your meter has a black reference mark. On the dial plate, usually in the lower right, is a conversion factor for that particular meter (for example Kh=7.2). To read watts, start counting seconds and disk rotations when you see the mark. Stop counting after a minute or after several disk rotations. The formula is watts = (Kh x number of disk rotations x 3600) / number of seconds. For example, you count 5 rotations in 64 seconds (7.2 x 5 x 3600) / 64 = 2025 watts. You can measure your whole home consumption or you can turn everything off and measure one appliance at a time. You may be surprised to see your meter turning when every appliance, including your refrigerator, is turned off. That's because "phantom loads," devices that are on even when you turn them off are still using power. Televisions, phones and answering machines with "power cubes," VCRs, etc. are some phantom loads.
I tried this and found over 200W of phantom loads!!!
I forgot to mention, read the instructions that come with the current transformer. When you are not using it, short the output. Otherwise it tries to be a potential transformer. If it drops 1 volt in the primary the 1000 turn ratio can easly produce 1 KV on the secondary. You would rather short the secondary to 0 volts and reflect that into the primary so it also has 0 volts drop.
This does not apply to the potential transformer. Shorting it is a good way to fry it.
The truth shall set you free!
We are in the process of building a Solar array for our summer home and I was blown away at the inefficiencies in DC to AC conversion. In fact they were on the order of 30% - 40% and the amount of solar power needed to maintain any sort of charge on the battery system was way more than expected. We found that finding a nice balance between AC and DC lighting would be the best win in our case as the efficiencies in DC to DC conversion (yes I was surprised about this one too) were much greater.
In the summer months there is more than enough sunlight to power our inverter system and keep the batteries charged enough, but we will have had to add a small hydro electric system for the winter months, which will allow for up to 40 AMPS (48V DC) which won't die through the night.
Wouldn't it be cool if our govt worked with Apple, Sony or MS and developed a standard residental power protocol that had similar features of IEEE1394 that you could plug into and get 12 volts && data transport??
If it was done correctly, your computer could have 1 cable attached and play to your stereo or TV.. Your TV could display your email. You would use waay less power because everything could go through a single transformer. You would have a lower risk of fire, and 99% fewer cords and cables tangled up everywhere.
I feel a little like that guy in Brazil but instead tubes I have wires everywhere.
-Scott scott@surrealistic.org
Umm, what?
The exact same thing is true of 110v AC, you just need to spend $30 up-front to buy an inverter. Then you can power your desktop computer from your car's cigarette lighter, solar panel, wind-powered turbine, hamsters, etc.
In fact, the easier way to do this would be to hook your power source directly up to the 12V battery in your UPS, since it already has an inverter, convenient outlets, and a serial or USB cable to attach to your computer, through which it can effectively monitor the status of the battery, and automatically shut-down when the electrical supply isn't keeping up with demand.
Slashdot gets worse every day... Pipedot: News for nerds, without the corporate slant
There are large differences in light load efficiency depending on the regulation method used (e.g pulse width modulation versus pulse frequency modulation).
:
:
However, every increase in the efficiency at light load will cost an extra few pennies (better filters, smarter controller, bias circuitry that does not rely on a minimum switching frequency) so that cheap (i.e. most) power supplies will not make this extra effort.
The best way to change this would be the requirement on the PC Manufacturer to put a sticker on the box stating
"Assuming 8h operation per day at full load, this computer will require XXX Dollars worth of electricity over a 4 year period."
With $249 PCs at Walmart, we are not far from the point where the electricity bill is higher than the price of the computer
4 [years] * 365 [days] * 8 [hours] * 150W = 584KWh
At 15Cent per KWh, this is 87.6$ over three years.
If you do not turn your computer off and it has no useful idle mode or runs Seti At Home, you end up with an electricity bill of 24/8 * 88$ = 264$ over 4 years - more than you initiatially spent for your PC.
If you are serious about rolling your own, check out:
http://www.edcheung.com/automa/power.htm
Enron has been shutdown for months!
There is a big problem with this, without going into technical details, it is very hard to run low voltage DC very far due to line losses. Runs of more than 50 feet are almost impossible with 12 volt DC, and even those require extrememly large wires to avoid voltage drop. It gets a bit easier with 24 and 48 volt, but that does not help much inside a computer case where the typical largest power draw being on the 3.3 volt rail fromt he processor.
Ike
Probably an easy (DIY) way would be to point a web camera at your meter. If you have a digital meter (like me) simply have your computer OCR the meter and indirectly convert this to instannous watts/kilowatts. If you have the older model with clock arms and a spinning meter...you would have to implement a more sophisticated method. I think this would make a great open source project, since once written, the software would be very reuseable with minor hardware costs for web cameras..
The cheapo power supplies used in PCs cost less than a tenth of that. Many of them don't have protection circuitry and forged UL certifications are common. Most won't deliver their rated load, and many, if loaded up to their rated load, will burn out, or worse, catch fire.
The real problem is to get to 90-95% efficiency at $0.10/watt.
Actually what would be cool is -48 volt DC supplies. Where I work we make a bunch of telco type equipment and one of the big requirements is the ability to run off of -48 volts DC. 48v is a lot better than 12 since the amount of current required is 1/4, hence the amount of power lost in transmission is significantly lower. Also, -48v is a nice multiple of 12v, so using 4 12v batteries in series makes a nice UPS, so UPS are also cheap with virtually no loss due to switching up to 115VAC.
This post is encrypted twice with ROT-13. Documenting or attempting to crack this encryption is illegal.
That has nothing to do with UPS's though. Which is what we are talking about goofball.
Its called a flywheel, and they do exist, but theyre not usually practical. As a sibling poster pointed out, it'd have to be heavy to store any kind of useful energy, and then if you bumped your case, it goes off kilter, tears through the aluminium and takes some poor kids head off. I dont think anyone wants that.
"Sic Semper Tyrannosaurus Rex."
I have a wife & todler and live in a 5 room apt (2 br, 1 bath, kitchen & living/dining room) and we use very little power. Granted we don't have a washer, drier, water heater, or electric heat. But we pay attention to our power use.
1) our tv (27")& dvd/vcr is on an outlet run by a light switch. TV's have instant on where they are charging the capacitors all the time. ITs not like the old B&W tv's that had to warm up. Also, the vcr drains power displaying the time and what ever else it needs to do.
2) The computer stays on most of the day (7ish - 11ish), its a 200w pwr supply and I've got a raid 0+1 on 4 drives. the 21" monitor which is an IDEK iiyama from circa 1992 is turned off when we are not using it. If we leave the house for a few hours we will pwr down the computer and flip the surge protector and turn off the wap, cablemodem, printers(if on), and speakers.
3) we use the toaster oven & microwave more than the regular oven & stove top. They use way less energy. If I'm only heating up some french fries and dinner rolls it takes less to heat up a small toaster oven that a large stove. The fridge we can't do much about, its ancient, we just don't open it more than we have to. THe more it's opened the more it has to cool back down.
3) lights, we have energy efficient bulbs, they cost $0.39 each after the rebates from effiency vermont. We turn them off when we are not in the room.
4) We only have one clock that is plugged into an outlet, the other clocks in the house are battery operated and the battery will last 2+ years.
5) we unplug the wallwart for anything we it is not being charged/used.
The only things that may be left in to suck power when not in use is a radio down stairs and the one in my daughters room that we leave on at night for her.
6) the a/c in the summer time, I've insulated as best as possible around the window it sits in. I ahve it on a timer, it only comes on at night in my daughter's room to help keep her cool. It's on from 7- 12, by that time it's cooled off enough and the cold air stays in pretty well. We adjust the shades/blinds to keep as much direct sunlight out of the apartment and from heating it so we don't use fan's very much. Only when it is above 80 degrees.
So less than 200kwh per month is possible for a family and you can still watch a decent size tv & have a computer on all day. Even if we forget to turn something off or unplug something, its not that big of a deal. Plus living in a town that owns it's own electric company, I have never seen a bill for my place over 27$.
~bigmoose
is more likely for common PC supplies. Otherwise PCs will be smoking...
Unfortunately a switch mode power supply would have low efficiency when it too lightly loaded or at its full load. The static load is usually higher for a bigger power supply while the I2R losses is smaller for a big power supply. At 50%-75% rated load is the sweat spot for highest efficiency.
The moral of the story is to pick the optimal sized power supply.
How 'bout a pluggable DC power strip to replace all my bricks.
You could have a nice long power strip that plugs into the wall and then runs DC along the strip. At each plug you could have a setting for volts and amps and then you could simply plug in your scanner/printer/usbthisorthat and not need a giant freaking brick on each freaking cord.
If you had to dumb it down for my mom and yours, you could make a special plug for 9v15A or 4.5v or what have you (polarity considered). There are enough commonly used DC power supplies, but each manufacturer has to reinvint the wheel for each freakin device. Pain in the ass.
I guess instead of waiting for the industry to create a nice and neat standard setup like the one described above, we could homebrew it and cut off the bricks and plug in the wires.
Patent Pending, so fuck off evil corporate bastards.
http://jclark.org/weblog/2004/01/11
someone do this. Please.
Bring the USA into line with the rest of the world and use 230VAC instead of 110V. This halves the current through the wiring, thus halving the power wasted
And you can pay for ripping out and replacing every wire, plug, powersupply, and wallwart.
Thing is, it would be nicer if we could all change to better standards. In most of America, the entire phone system, power grid, gas/water/sewage system, unit measurement standards are really screwed up. But, they are standards for a reason; Everyone uses them, and they don't want to change.
I'm really curious how big K is....
I tend to leave the external power supplies for my laptop plugged in all the time, even when not connected to the laptop. Is the juice thus wasted truly trivial, or is it enough to worry about reaching down/around to unplug?
plus-good, double-plus-good
Hey, if everyone switches to Apple computers think of the power saving across the world !
(Macs use 25-35 % less power on most machines due to lower power draw on the CPU)
Maybe the goverment should subsidize buying Macintosh computers...
{ Pillar candles great for when the power fails and you cant see the keyboard..
I've been wondering about the same thing. An interesting addition would be to allow it to monitor the current price of energy (various websites) and enable/disable devices based on the current price.
Setting a delay on a dryer is useful for pushing it to 2am. Telling it to turn on when the price hits 3.5cents per kw is even better.
Rod Taylor
There's a big reason not to use those flourescent bulbs - they contain mercury, which goes into the environment when the bulbs fail. I've used many different brands of flourescent bulbs, and the advertised claims of long life are utter lies. They fail just as often as incandescents.
Here's a tip: Put all of your wall-worts on a seperate power strip from your main machine. Make sure that power stip has a hard power switch, not some standby crap. If at all possible, get a strip with a hard power switch for each outlet. When a wall-wort isn't used, flip the switch to keep power from being wasted. I have 2 of those under-monitor multi-switch power strips with individual switches for my workstation. The computer switch is on 100% of the time as I never, ever turn my machines off. But all the component wall-worts get shut off when I'm not using them.
"Why do you consent to live in ignorance and fear?" - Bad Religion
Don't forget to add a factor of 2 or so since all that heat released in the office buildings usually (at least in the summer) requires the air conditioning to work that much more.
Anyway, I use the heat factor as an argument so I can leave computer on, idling, in the wintertime, but try to save in otherwise.
Normally I don't reply to rant and rave freaks but..
The cost would be minimal. New wall outlets are about $1 per. Standard romax wiring is good up to 600 volts, and if you really wanted to, just rejumper your panel since most households have 220 volt service anyway. You'd be out of luck for breakers, those are still about $10 per or higher depending on amperage/features.
And getting down to serious techie geekness, most any electronic device today has internal jumpers for 110/220. You could put a proper 220 plug end on it and you are good to go.
No real need to do it for anything that draws less than 60 watts though, and lightbulbs would be a problem if you really wanted to get into all 220.
That is the answer. Running DC to the computers. California, Texas, Arizona, etc., etc. If you want the cleanest power - hey - I'm talking sine waves here - brew your own DC on the rooftop, around the office, and put in some batteries. Mobile AL has some of the dirtiest power for being brown (undervoltage) and jagged what with all the lightning strikes. Computers last longer with cleaner power. So it is just a little bit more expensive. It means that you have more control over your system. If shit happens, your puters are still up. It should be the wave of the future, but then Reagan gutted aid to solar power in the 1980's.
if there's no juice, where do i plug in my "big monitor"? otherwise you're right though; just use the laptop as a LCD monitor..
Facts do not cease to exist because they are ignored. - Aldous Huxley
Since I was a kid. And as you see i'm alive. It all depends where the current runs. If it runs between 2 of your fingers, but you won't get killed. If it runs through your chest (one hand 220V, other hand or leg grounded) or similar, it'll get nasty, and I don't think 110V instead of 220V would help much.
:\ These fuckers in university couldn't care less about their own students...
Last time it was a badly connected plug in an ELECTRONICS lab in university. The steel screw in a plug was connected to one of the wires. I scolded the lab assistant, then took a screwdriver & my knife and fixed it myself
--Coder
A stupid question, but why doesn't the graphics card power off when the monitor timeout kicks in?
I'm sure my PC could be using a lot less power when its just sat doing nothing.
The RFI output of CFs is pretty bad. I have to turn them off to receive some weak AM stations. My CRT monitor causes the same problem.
Contribute to civilization: ari.aynrand.org/donate
if you scum sucking leftists pigs hadnt blocked nuclear power, we wouldnt have an oil war, and oil crisis, peak oil or the need to fuck with these made in china SHIT fucking power supplies and make them more efficient.
FUCK YOU PIG FUCK FUCK YOU commies fuck you.
Slow Down Cowboy!
How about this, fuck you fat pig cowboy neal. ill post when i please, im rick james, bitch.
One of the big energy wasters in current PCs are those way too big PSUs. Most PCs consume something between 100 and 150 watts. Most PSU are designed for 300 or even more watts. Switching power supplies are more efficient than older models, but even those reach their maximum efficiency only at or near their peak output.
... But choosing a high efficient *and* correct (=enough) output PSU is one of the most important.
So if you want an efficient PSU be sure to buy a high efficiency but low watt PSU. (Those Mini-ITX Boxen come supplies with a 60 watt PSU).
There was a very interesting article in German computer magazine c't (sorry, not available online) that discussed the use of mobile CPUs in desktop boards. The conclusion was, that in a normal PC only half of the power savings of the CPU transform into real power savings. When you put an Mobile Athlon in your board (as I do) your CPU uses around 30 watts less than the normal Athlon. But in a real PC only 15 watts will be saved. The rest is still wasted in the PSU. (of course a 30 watt CPU is still much easier to cool, so I think it's still worthwile)
Btw. the second big source for power wasting are all those power regulators (correct term?) on your mainboard. Ever wondered why some mainboards come with heatsinks on them?
Building a really efficient PC is not a simple task
Bye egghat.
-- "As a human being I claim the right to be widely inconsistent", John Peel
have a look at bones, snails etc and many marine creatures - all include Carbon locked into calcium carbonate - much of the marine carbonate falls to bottom of ocean thus removing it from the atmosphere - similar schemes have been proposed for industial removal of CO2
However emissions from transport (cars aviation) is a major source and will need to be curtailed
I thought I'd add a few interesting ideas and resources to this discussion.
...and various other quantum-effect computing technologies.
Check out the works of Amory Lovins / L. Hunter Lovins / Paul Hawken;
they have an interesting book which can be read free online or be purchased
in print depending on one's desire --
Read 'Natural Capitalism' free online or buy the book!
Read 'Natural Capitalism' free online
Read 'Natural Capitalism' free online
Amory Lovins has a lot to do with the Rocky Mountain Instutute
Rocky Mountain Instutute and there's a lot more information about efficient
technologies and industrial / social evolutions there.
"Natural Capitalism: Creating the next industrial revolution" is all about
paradigm shifts that evaluates efficiency and resource conservation as
being key factors both for environmental reasons as well as economic reasons --
economics is about the market prosperity of the most efficient products and
services, and surely there are disadvantages in inefficient use of one's
inputs.
"Achieve multiple benefits with single expendutures" -- and the book/ebook
is full of really thought provoking and compelling practical paradigms to
illustrate the power of that thinking!
Ok so my next salient point and resource on the subject of power supply efficiency is to look beyond the power supply to the load and realize that
computing itself can be as close to a "zero power needed" technology as one
cares to implement. Current digital circuits waste the vast majority of their
power by irreversably converting 1's to 0's and 0's to ones, basically charging
up capacitors to make a high voltage "1" where there was no voltage before
and then wasting all that energy a bit later shunting it to ground / zero volts
to make a "0" again. This isn't necessary to achieve the computing function!
And here are some interesting readings on that area:
"Reversible Logic" is one such practical approach to it --
Article At MIT
http://www.google.com/search?ie=UTF-8&q=%22rever si ble+logic%22+%2BMIT
And otherwise: Book Info: "Complexity, Entropy and the Physics of Information"
"Complexity, Entropy and the Physics of Information"
a great read on the relationship between information theory, computing,
and thermodynamic entropy's relationship to data entropy, even touching
on how many "bits" of information a black hole must accumulate based upon
the entropy of the infalling matter/energy!
Besides classical circuit theory implementations like "Reversible Logic"
to save power there are very exciting opportunities in other quantum-computing
technologies like "Spintronics" (e.g. using the spin-quantum of currents flowing between magnetized metals / semiconductors to represent "1", "0" or
multi-level logic which is basically related to the way a NMR device gets
its signals):
Spintronics
Google It
As for efficient power supplies, how about one that's 99% efficient,
generally non-toxic, cheap to manufacture (actually it's self manufacturing!)
and generates perfectly 'clean energy'?
Wired: Algae based fuel cells!
How about using the same kinds of photosynthesis that every green plant
on earth uses to split Hydrogen apart from Oxygen and create a microscopic
electrochemical fuel cell complete with the option of integrated
efficient 'storage batteries' for holding power when the sun's no
That's exactly the point.
If I were to give you two 21" LCDs, your cubbyhole would suddenly be less cramped and you'd be happier.
Maybe not as much happier as if I gave you real walls, but we're talking maximum happiness for the dollar.
[assuming the LCDs were up to the task.]
This is not a political statement. This is not legal advice. It's a frick'n Slasdot post. However: I'm Running For
.......but even those reach their maximum efficiency only at or near their peak output........ Not really, this is a myth - Computer Multi output PS reach maximum efficiency at or near 50% loading - based on testing several dozen power supplies...go to INTEL's form factor website and you will see the recommended efficiency levels for ATX and other form factors are higher at 50% loading.....
there is no commercially available 90% or 95% PC power supply in the world!! There are many DC to DC or single output AC-DC power supplies that can reach +90% efficiency level - but not multi output AC-DC power supply for PCs with ATX12V or other form factors. In addition to cost, the technology for making a multi-output AC-DC power supply with universal input voltage is difficult. The most efficient PC power supply that I am aware of is made by Celetron (http://www.celetron.com/Power-IDF-2003.pdf) which is in the range of 85%. will be very interested to see if anybody knows about a PC power supply (multi output) that is > 90%
The discussion is already old, hopefully some of the EE who participated still read it ...
Let's say I am convinced and want to start using more efficient power supply now. First thing, I checked the spec for my PC PS at http://www.antec.com/specs/true330_spe.html. I used to think this what somewhat of high-end power supply, but I can see that the rated efficiency (in the Input section of the table) is only >= 68%. Is this normal for consumer-class PC power supply ? Any suggestion of PS with better efficiency ?
Something else: would it be worth it to replace all the power brick of my computer accessory (cable modem, hub, speaker, etc) with a standalone power supply with multiple voltage output (if such a thing exist) ? If yes, what would you recommend ? I guess finding "patch" cables (PS -> devices) with the appropriate connector could be somewhat of a problem, unless they standardized. A nice side-effect would be to cut the cable clutter.
:wq
On cheap (consumer) UPSes, yes. On high-end equipment, you're running off the inverter the whole time, so there's no gap in power when the AC goes down. The rest of the time, you're running off the AC-DC-AC circuitry as the battery is continuously charged.
± 29 dB