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Saving Power in your Home Office
cweditor writes "Rob Mitchell shows how he measured energy use of all his home office equipment, and then targeted the energy pigs for replacement. With better equipment choices, he'd save $90/year. If you've got more than a couple of computers and printers at home (and if you're a Slashdot reader, you probably do), the savings would be a lot higher. Includes detailed formulas as well as a spreadsheet on monitor energy usage."
For those of us who need to think bigger EnergyStar has a report and ways to cut energy usage for a whole data center... But energy saving starts at home.
Ask not what you can do for your country. Ask what your country did to you
The Kill-A-Watt (and its competitors) are a handy item. I was surprised to find that my desktop PC was pulling 118W doing "nothing" and 139W when working pretty hard. Even more surprising, when I switched to Volt-amp mode, the numbers were 189 and 210 VA, respectively. My office is usually too hot anyway, so I figured that was a good excuse for a new power supply. I got an "80 Plus" power supply, and now "Hymie" pulls under 88W/89VA when slacking and about 95W/96VA breathing hard. The power factor correction isn't just a gimmick. The case is much cooler, and I unplugged several of the now-unneeded fans, saving a couple more watts. On top of that, my immediate desk area is more comfortable and quieter. See website http://80plus.org/ for more info on "80 plus" program.
I am not a crackpot.
Give me a break. Turn your house up 1 degree in the summer and down 1 degree in the winter and you will save more money than that!
"TV, a medium as it is neither rare nor well done." Ernie Kovacs
It said the new LCD was better on the eyes. I think it worths $200 to not ruin your eyes...
But i agree, he probably spent 5x more to save $90.
Patents Drive Free Software as Hurricanes Drive Construction Industry
If you want to estimate the manufacturing/energy costs, multiply the wholesale price by x2
Then compare that to the estimated reduction of your energy bill over the lifetime of the item.
If that LCD costs $100 but saves you $90 a year, then you will break even after about 2 years and start saving energy (and the Planet).
Obama likes poor people so much, he wants to make more of them.
Where I live, electricity is about twice as expensive as natural gas for heating, so heating with waste heat is not quite as economical as one would think. Plus it's an extra liability in cooling season. But when I heated with resistive electric in an apartment, I too didn't worry too much about leaving things on in the wintertime.
I am not a crackpot.
In terms of grams of CO2 per candela, a candle has a carbon profile worse than that of an incandescent bulb. Beeswax candles are an exception but most paraffin wax is derived from petroleum.
Multiplying Amps by 127 doesn't take power factor into consideration and gives you VA, not Watts, unless your load is purely resistive. It can give you a vague idea of whether you're saving any power or not, but not always since electronic and inductive loads can draw current at different parts of the AC waveform such that a clamp ammeter won't show.
There's a short explanation of the difference here: http://www.powervar.com/Eng/ABCs/CalcVAWATTS.asp
Putting moderation advice in your
Beyond the question of whether or not anyone 'needs' even one computer, some of use just do it cause we can, or because we want to. I still have an old laptop on my network for no other reason that when it got replaced, it got several different linux builds tested on it and then stuck in a corner, chugging away at Folding@Home and acting as my print server. It was a great learning experience, getting the different platforms (two different windows versions and a linux box) to all talk and play nice and friendly (i.e. beyond using a common internet connection). Some people use old computers as firewalls, routers, file servers, etc. and some people simply can't throw things out. There's a second desktop that I use for playing older games that don't run properly on newer OSes, but it's off unless I'm using it. I've probably got parts enough to build two or three computers (less cases) stored in my closet because there's no reason to throw out old but working parts. I would say that is probably true of a signifigant number of Slashdotters.
Anytime some one says "Oh my is broken", I've probably got a replacement and I simply give the part away. I admit that having a bunch of computers running 'just because' is probably wasteful in terms of electricity cost, but throwing them out is wasteful if they're just going to sit in a landfill.
Lose: misplace or fail || Loose: not bound together
This article is kind of timely, as I just got a Kill-A-Watt on Tuesday for the purpose of measuring office equipment electrical usage. What I found was that my old Athlon64 3200+ (1 gig of memory) was drawing 100 watts idle, while the new Athlon64 X2 5400+ (2 gig of memory)that I just got to replace it runs at 40 watts idle. Given that I am paying $0.32 kwh for my top usage, that comes out to a $14.29 savings per month by purchasing the new, noticeably faster machine. Given that I paid $150 for the motherboard/processor/video card/memory upgrade, in 10 months, the machine will have paid for itself if both would have been left to sit idle. The normal usage numbers are 120/77 watts which comes out to a $10.07 a month savings if both machines were run under normal loads 24/7. The new system also has WAY better power management, so I'll actually use it. This means that when I am not using the system the numbers will be 100/5 watts, and a savings of $22.25/month. Based on my usage patterns, I expect about $15 a month in savings.
After seeing these numbers, I decided to check out my wifes machine. Her system has the known Windows bug that makes it go to the "It is safe to shut down your system" message instead of actually shutting down when the computer is instructed to shut down. This combined with her usage pattern of sitting down and looking things up for 5 minutes, then walking away for the computer, and coming back 2 or 3 hours later to spend another 5 or 10 minutes on the system, means that getting her to turn off her computer when not in use is simply not an option. There is no way I am going to convince her to wait the 3-4 minutes waiting for it to boot up, and another 3-4 minutes waiting for it to shut down, to get 5 minutes of use out of it. Her machine runs at 110 watts idle, and 150 watts under normal load. Given that the new motherboard has suspend that actually works, 99% of the time her system could be running 5 watts with, again, better functionality. This would lead to a savings of $22.25 per month in savings. This would mean giving her the same upgrade would pay for itself in ~7 months. You can bet I am going to do that very soon. I expect that my son's system is only slightly more efficient than my wifes, so his will likely follow shortly after.
I have a small 1200sqft home and my electricity bill is over $400 per month. We went around the house and tried to figure out the biggest hogs. Nothing seemed off par until I went into the garage and noticed that the fridge and freezer were running. So I sat down for awhile with a book and listened. It was summer and these things were running 25 minutes out of the hour. Then i went inside the house and it was no more than a total of 10 minutes and hour. I disconnected them for 2 months and saw my bill drop over $125 a month! I no longer have them in my garage. I later read that they should never be in a garage unless it is climate controlled. I bought a bigger unit for my house and no longer need them anymore.
Mike18067
www.slipcoverhome.com
Additionally, I have a radio remote controlled master power button, to which I've connected all monitors, speakers, chargers, and everything else non-essential for running the computer. This makes it easy to kill all power while still leaving the computer on. A bit more power could perhaps be saved by using an even better power supply, but not buying it will probably save more money and environment.
True confidence comes not from realising you are as good as your peers, but that your peers are as bad as you are.
My next $5 will be spent on a timer for my overly large tv, satellite box, surround sound system, (leaving the TiVo intact for late night recording)etc. to kill standby mode on that stuff as well. I am saving more passively than the guy is actively managing his power.
No. A full load in the dishwasher actually uses less resources than doing dishes by hand. And the dishwasher will actually clean and disinfect the dishes properly, whereas most people doing dishes by hand won't actually kill all the bacteria while using at least twice as much water.
Don't replace things to save energy. Just make energy conscience choices when the time comes to replace things.
The idea is if you don't buy the new toy you don't discard the old one.
EX: I had a 91' Volvo with ~230k miles which I replaced a few months ago with a brand new Acura TSX. The Acura get's ~50% more miles to the gallon but costs 500$ month. If it had cost 700$ a month I would have probably kept my Volvo for another few years because I don't drive all that much.
PS: Yea the car analogy is messed up because there are several reasons to buy a new car. However, when things cost more the tendency is to stick with what you have.
There are many energy-saving questions I'd like to see investigated. For example, I have an old Subaru, and I'm not sure if I should buy a new fuel-efficient car. Mine isn't a guzzler, and I can afford a newer one. But that new car, even if it gets twice the MPG, costs energy to make--would an extra 20mpg offset the energy cost of making the car, and if so, how long would it take?
There is more to the question than just gas savings. Repairs and routine maintenance are another part as well as resale value. My wife and I both bought used cars in 2003. We both bought 2002 vehicles for $18,000. Hers has 80,000 miles and mine has 101,000 miles.
Let's check current bluebook...
2002 Dodge Caravan Roughly $6-8,000
http://www.cars.com/go/crp/research.jsp;jsessionid=JOG2KH0OBPGX1LAYIESU2UY?makeid=12&modelid=127&year=2002§ion=summary&mode=&aff=national
2002 Toyota Prius Roughly $16-17,000
http://www.cars.com/go/crp/research.jsp?makeid=47&modelid=2916&year=2002§ion=summary&mode=&aff=national
The Dodge has already needed a brake pad replacement, power steering service and other items. The Prius has no engine belts except for the AC. The power steering is electric, not hydraulic. I had the brakes checked at 80,000 miles when I changed tires. There was 80% remaining due to the use of regenerative braking.
Just from the above, it is easy to see which is the winner on value.. and we haven't touched gas cost yet.. OK what about the gas?
I bought the Prius used with 8,000 miles, so I have put on 101,000 - 8,000 or 93,000 miles since I bought it. Gas went from about 1.50 a gal to over $3.00 a gal. For sake of argument, lets use the average of about $2.25/gallon. I have averaged 46 MPG. I bought approximately 2,022 gallons for a cost of approximately $4,550. On the other hand the gas for the Caravan is over $10,000 spent. At over $3.00/gallon, the savings are more dramatic. For the same distance driven it is either a $30 fill-up or $70.
People often argued that the cost savings in gas will not pay for the premium for buying a hybrid. If you drive a car that gets less than 1/2 that of the Prius and you drive it more than 100,000 miles, and you can still get gas for $2.25/gallon, then the argument is almost valid as this is the break even point on the additional price premium.
I bought the car when the price of gas wasn't over $2.00/gallon. I studied them and found they are not new tech. They were on the road for 5 years in Japan before they hit the US market in 2001. I was impressed with the reliability and the elimination of most of the expensive over 100,000 mile failure items. Items like alternators, power steering pumps, hoses, starters and the like are eliminated. I also knew gas prices were going up and were never returning to under $1.00/gallon. Future gas prices meant future savings. A surprise was just how high the resale value is. That is an added bonus.
One of the big scares of buying a hybrid was that big expensive battery. It is common knowledge batteries are useless after about 3 years in your cell phone, laptop, etc. I'm going to have to buy a $5,000 battery in 3 years... there is no savings as gas savings will need to be spent on a battery every 3 years. Part of my studies was to deal with just this fact. In digging I found the truth, and it's very nice and was the final item that got me to buy one.
Here is the deal on the batteries... Cell phones, laptops and such deep cycle batteries.. BAD. You run them down past 50% and charge them up to the top.. Bad and bad.
The hybrid keeps the battery under 80% and over 50% with almost no exc
The truth shall set you free!
Then again, I still use some of those really inefficient halogen touchier lamps. I use CFL bulbs in the light fixtures that don't dim, but there's something really nice about being able to vary the light from intense and white for reading to warm and dim for movies or dinner.
While halogen lights are not as efficient as CFLs they are more efficient than incandescent lights. As for using CFLs with dimmer switches, there are some CFLs capable of dimming. Though they are more expensive here are some dimmable CFLs. Though I don't see where they say what the manufacturer is on that page both GE and Philips make dimmable CFLs.
FalconShould there be a Law?
Warning... This is a long post, but has specific info on how we did it. If you are really interested in saving energy regardless of your motivations, read on.
;->. We incorporated these ideas in our old location, but we had no idea how much we were saving because power was included in our lease.
We are a small IT company in Colorado that has always had a thing for saving energy. To all you "green" folks out there, no, we did not do it to reduce our "carbon footprint" or any such psudo-math. (I will retract this statement if and when someone can show me hard math and facts where the data doesn't come from a table generated by an "expert"). We simply saw the need to reduce waste, and did what we could. The fact it would help our bottom line didn't hurt either
Recently we moved into our own building, and got a real power bill. The first one doesn't count since we had the deposit to pay and contractors with power hungry tools... but our second one was $37, and no, that is not a typo. The subsequent bills were within 20%. What was done to make this possible was three-fold, Habits, Building, and Equipment.
Change your habits. If you are done with something, turn it off. We power down half the servers and some IT gear when we leave for the night. Laptops get turned off or leave with the employee. Lights get turned off when you are not using the space. These habits were solidified in the old location.
The building we selected is a 1920's adobe with about 2200 square feet. At our altitude (nearly 7000 feet), we needed no cooling except for the hottest months. The rest of the time we pull cool air from under the wood floors as needed. The office stayed at about 70 degrees, and the A/C kicks in at 85. All the area lights have been replaced with compact flourescent and task lights are LED spots. The break room has a small energy efficient fridge and microwave. No real surprises there, but the big savings is in the IT side of the house.
Most of our real power consumption on the AC side are the printers. We have 3 laser printers, 2 B/W and 1 color, that we keep turned off when not in use. I wish we could move to something more energy efficient, but in business, there is still no replacement for a laser printer. We also have an inkjet/fax/scanner/dishwasher combo (just kidding about the dishwasher bit), but it also runs on AC, and stays on nearly all the time. We use it mostly to print proofs before they go to the laser printers for production.
We have 8 pieces of non-computer equipment (phone systems, routers etc...) that run on 12 VDC and 3 run on 5vdc. We selected the equipment because it ran on DC at one of these voltages. Wall warts are just miniaturized linear power supplies; they draw power whenever they are plugged in, and produce heat, even when they are doing nothing for you. Switch mode supplies, such as PC power supplies use power in proportion to their demand and are most efficient at 70-80% load. We use a 500W dual output switch mode power supply to power everything that normally has a wall wart, charge the battery banks for failover... sort of a UPS with an 24 hour run time, and all the servers.
Waitaminute... Servers??? Yep. While you may think you need God's own server for what you do, take a real look at it. We had a file server, 2 web servers, a mail server, an applications server, a database server, and a development server. They were mostly dual P4s with one single CPU. We replaced the servers used for the file and mail servers with one box with a Via C3 processor, 200W 12vdc power supply (for ITX machines), dual 500GB hard disks and 2 GB RAM running CentOS. It is plenty fast for our work group of 4 office people, 4 techs, and 2 sales weenies. In fact most have commented that it "feels faster" than our old SMP machine running 2000 Server. Better still is the power consumption... about 3.5 amps on the 12V line, or 42 Watts. Nearly identical machines run as our web servers, a combined application and database serve
But yes, overall, simplifying our lives and living situations would go a long way towards reducing our energy footprint; but we should also avoid false optimizations.
- "History shows again and again how nature points out the folly of men" -- Blue Oyster Cult, 'Godzilla'
I look for the new 80 Plus rating whenever I buy a new power supply for a computer. The 80 PLUS performance specification requires power supplies in computers to be 80% or greater energy efficient at 20%, 50% and 100% of rated load. Many computers come with much less efficient power supplies. I used an 80 Plus rated power supply in the most recent computer that I built. On my slightly older computer, the power supply recently died and I replaced it with an 80 Plus rated power supply.
Another problem is the energy consumption of inefficient auxiliary equipment with transformers which consume power even when the device is off. Those cheap poorly designed external transformers are sometimes called "vampire taps." The Smart Strip Power Strip could probably help there. When the Smart Strip senses that you've turned your computer off, it automatically shuts off your peripherals, too, preventing them from drawing an idle current. It does that by sensing the flow of electrical current through the strip's control outlet.
By the way, I live in the U.S., where we use 120 volts.
What is 80 PLUS
Smart Strip Power Strip
Dad's Computer
Mom's Computer
Kids Computers
Dad's printer - Laser
Mom's Printer - Scanner/Injet
Kids Printer - injet
and that's just in my house. Dad's printer is used for work, Mom's is an all-in-one and the kids get basic injet for school work, while ensuring when they run out of ink/paper, it's doesn't mean dad's out.
Add in a home network and I've now got all three desktops Folding 24/7
This of course doesn't count the Media Center (don't have one anyhow) the fact that there's a home NAS, Dad/Mom/Kids all have backup folders on them. Plus doesn't include the game consoles, Gaming Rig, and so on. All told, there are 7 computers in my house running 24/7 for a total of 5 people (3 pre-teens).
Now if you asked are they in use all the time then Hell Yes - Folding at Home on all of them and every system is as energy saving as possible.
Mod me up/Mod me down: I wont frown as I've no crown
Not mine. Used to when it was new, but not lately. Have to rewash things constantly which leads to more resources being used (including time). And before you start, its only 6 years old and I don;t thing replacing all our dishwashers every 5 years is efficient use of resources either.
We do not inherit the Earth from our parents. We borrow it from our children.
It just seems to be a shallow field--either the Prius, or the Honda Civic Hybrid.
You haven't been paying attention and it shows.
http://www.fueleconomy.gov/feg/hybrid_news.shtml
Toyota in addition to the Prius has the Highlander and Camry.
Thanks for the info--it was this kind of post I was hoping for.
You are welcome.
The truth shall set you free!