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."

Comments

Saving elsewhere

[luvirini]

A typical slashdotter will likely save way more both nature and money in a year by just not buying one of the gadgets..

Ofcourse saving electricity is good, but often the total enviromental cost of disposing of the previous thing and the making of the new more energy efficient thing is way above any savings made by the new one..

Re:Saving elsewhere

[eln]

The average Slashdotter already saves energy in a variety of ways:

1.) Cutting showers to less than once a month greatly reduces both water and electricity (or gas) usage.
2.) Staying in Mom's basement not only drastically reduces greenhouse gas emissions from automobile usage, but also eliminates all the extra energy waste that maintaining a separate house would entail.
3.) Not dating ensures procreation will not occur, thereby eliminating the energy usage involved in having more people on the planet.

As usual, Slashdot is way ahead of the curve on this issue. Unfortunately, 90% of these savings are used up by the racks of ancient computer equipment still running in many of these basements, but every little bit counts.

Re:Saving elsewhere

[Otter]

Sincere question -- why on earth does any one person need more than a laptop, a desktop computer with monitor and one printer at home? (OK, I'll throw in a "media center", also.) Not that one necessarily needs even that, but I'm always baffled by these comments here about home networks that sound more like 15 person businesses.

Presumably there's an answer, but cross-platform development is the only one I can come up with, and are there really so many people compiling on VMS at home?

Re:Saving elsewhere

[plague3106]

Hell, why do you need your own house? Surely an apartment is good enough for you? Even that's wasteful, why not just live in a building with shared bathrooms and beds. Who needs lights at night anyway, or a TV for that matter? Surely not buying a washing machine would be more efficent too, just do your dishes in the sink. Its also a waste to travel, so lets live at where ever we are employed. And you get one plate to call your own. Who needs more than that?

Re:Saving elsewhere

[TheDormouse]

Surely not buying a washing machine would be more efficent too, just do your dishes in the sink.

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.

I saved!

[monkeyboythom]

I unplugged that appliance that measured my electric usage. However, the power company didn't see the benefit the way I did.

love to see more of this

[misanthrope101]

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? Money aside, I don't know whether to keep the beater (which gets about 20mpg) or get a newer car.

Also, what about TVs? I have a 19" old-fashioned TV. Cheap, and it works. But I'm looking at a 32" LCD. The LCD might pull less electricity, but would the difference offset the energy costs of making the TV?

Re:love to see more of this

[pinkocommie]

Craigs List? Or any other classifieds variants. You're making the presumption that both of those are going to waste when in both cases you'll be passing them on to someone else who would've gotten them from another source otherwise (which could be new or used)

Re:90 whole dollars

[eln]

How much money does it cost to save that much energy as well? I kind of scanned the article, but one thing I did notice was that $200 was spent on a new LCD monitor to replace the CRT. If we assume 100% of the energy savings came from that one purchase (which it didn't), it will take more than 2 years to recoup the money spent on that one purchase, and there was no indication that there was anything wrong with the older monitor other than that it used too much energy.

I would advocate buying newer more energy efficient equipment as your old equipment dies, but I would not advocate going out and replacing perfectly good equipment with more energy efficient (and more expensive) alternatives. It will not only cost you a lot of money, but will also mean more waste from throwing out perfectly good equipment that will likely end up in a landfill.

Kill-A-Watt and "80 Plus"

[Rob the Bold]

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.

Only $90/year????

[rimcrazy]

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!

Re:Only $90/year????

[mdalal97]

Why not do both? It is not that hard to reduce your consumption. Turn off your computers at night, unplug unused power bricks (for cell phones, cameras, chargers, etc...). It is easy. Just because it appears to be a relatively small benefit, it doesn't mean you shouldn't do it.

I thought the article was OK, but it did seem like he we dwelling on the 'sacrifices' he had to make... really, how hard it is to turn off your computers when you are done for the day. It is not difficult to make the changes needed to reduce consumption.

The problem implicit: no value for the individual

[skoda]

The author spent $200 to buy an LCD monitor to replace a 19" CRT, saving $18 / yr electricity: more than a five year payoff. And he's putting a CRT into a landfill somewhere. There's no economic incentive to buy an LCD; savings are pocket change and doesn't realistically pay for itself. And the environmental cost could be a wash, since the reduced carbon footprint is weighed against a CRT dumped in the trash.

This article is fun, and I might play a similar game at home. But people chasing $90 in electricity is nearly trite compared to the real energy users: home heating and cooling and clothes washers and dryers. Globally, this is spitting in the ocean compared to the real change that's (presumably) neeeded.

It's reported that eliminating coal-mine fires (http://freakonomics.blogs.nytimes.com/2007/10/22/from-bagels-to-coal-fires-an-unorthodox-economist-keeps-pushing-for-change/) would reduce CO2 emissions annually equivalent to that produced by all cars and light-trucks in the US. There's little value in individuals replacing 3 W cable modems for 2 W versions when the "easy" targets are still ignored.

I have another way of saving electricity

[ODD97]

I built a system that turns off my lights when I blink. My blinks last approximately 1/4 second, and I blink roughtly 20 times per minute, saving me 5 seconds per minute, or 20 seconds per hour. That makes 160 seconds (2 minutes) per workday. over the course of a year, that's 16 minutes of power waste that I am avoiding without changing any equipment significantly.

... of course, alligator-clipping the blink sensors to my eyelids stings for a little bit, but you get used to it really fast. It's a small price to pay to save the world.

Sometimes, the device is not the problem

[F1Rumors]

Rather, the brick that converts the AC to DC is inefficient.

My savings came from taking an efficient computer power supply (80-85% efficient, depending on the load) and running my own 12V and 5V supplies direct to the devices that use those voltages [includes: cable modem, wireless router, usb hub, network disk, a GPS/VHF radio and a camera]. When I can be find time to finish the job, I'll do the maths and buy the parts to add 19V and 6.8V for two other devices.

In practical terms: I no longer have a collection of bricks generating heat, so I waste considerably less energy; I plug only one device in to the UPS, eliminating a lot of wires, so the installation is simple and tidy; and there's a bonus: the fan on the power supply keeps air moving over the equipment whenever heat builds up...

Saving energy is easy... just do it!

[Anonymous Coward]

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 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 ;->. 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.

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