Stand-by Current - Does it really matter? - Page 1
Forum section: electronics / general

author: Unknown
author_rank: Unknown
timestamp: February 19, 2015, 11:11:36 am
content: Dave, this one could be for one of your EEVblab's...We constantly see news articles about "How much devices in stand-by mode are costing you money". I suspect it's largely click-bait, but is there any truth to it? I don't really have the appropriate devices (or time) to actually measure the "average" household stand-by device current consumption (USB chargers, monitors, televisions etc...)Sure, they all consume power, but is it significant?Discussion open :-)

author: Mechanical Menace
author_rank: Super Contributor
timestamp: February 19, 2015, 11:56:23 am
content: I've an habit of just leaving my PCs on, no sleep mode or anything apart from the monitor power down, just in case I want to set them going on a job or need to access some files. Everything else gets left on standby. Through what I can tell from my electric meter my house only uses about 40-50 watt when I'm not there. At a guess I'd say the none PC stuff is 5 watt of that. I don't feel guilty at all, and my "green" energy plan and small generating capacity has nothing to do with that lol.Standby isn't such a big deal on a home by home basis, you'd have to be looking closely to notice the savings by turning everything off at the sockets. It becomes a problem when you think of the millions of devices across whole countries sucking energy when not in use. Though I personally think the solution to that problem isn't getting everyone to turn them off but to encourage people to at least look into producing at least a small amount of the energy they use. An 100 watt solar panel per home would more than cover everyone's standby usage even here in the north of England.

author: wraper
author_rank: Unknown
timestamp: February 19, 2015, 12:49:24 pm
content: Yes it is costs money actually. For example, if you have some device that consumes only 5W but all the time. Not a big deal you think? Well, 0.005 kW * 24 hours * 365 days = 43.8 kW/h annually. Now lets take electricity cost here in Latvia which is 0.17 EUR kW/h * 43.8 = 7.45 EUR annually. Now let's assume you have 10 gadgets in your home always being in standby mode...

author: madires
author_rank: Super Contributor
timestamp: February 19, 2015, 01:22:04 pm
content: ... and I have to pay about EUR 20 per year for 10W 24/7. I love switchable power stripsBTW, I power my network und communication devices which run 24/7 by a central DC power supply, if necessary with a DC/DC converter. This setup needs about half the power of running the original wallwarts (mostly SMPS).

author: cimmo
author_rank: Frequent Contributor
timestamp: February 19, 2015, 02:32:08 pm
content: A few years ago, when most devices and wallwarts were powered by an iron core traffo, standby power could easily add up to some significant numbers (5 to 20w+ per device?). We may have more gadgets now, but as the switchmode converter is almost ubiquitous, the standby per device is often less than one watt.

author: dexters_lab
author_rank: Unknown
timestamp: February 19, 2015, 02:44:06 pm
content: doesn't matter much to you personally but nationally and globally yes...250 million devices drawing 2 watts on standby = a nuclear power stations worth

author: Neilm
author_rank: Super Contributor
timestamp: February 19, 2015, 07:53:42 pm
content: It certainly matters in Europe - I think the CE declaration now includes standbys having to be less than a certain power for consumer items.

author: funkyant
author_rank: Unknown
timestamp: February 20, 2015, 11:01:54 am
content: Quote from: dexters_lab on February 19, 2015, 02:44:06 pmThis. Worldwide there must be a LOT of wasted energy on devices that are not even being used.

author: AndyC_772
author_rank: Super Contributor
timestamp: February 20, 2015, 12:26:22 pm
content: Don't underestimate the extent that public and political opinion can be swayed by how easy something is to understand, rather than by how significant (in percentage terms) something actually is. Anyone can grasp the concept that:standby power == wasted power...and...wasted power == bad...therefore...standby power == bad...without any grasp whatsoever of the figures involved.Suppose a product draws insignificant standby power, but when operating, its cheap PSU is inefficient. Why doesn't this get the same coverage in the popular press? It's still wasted power, but because it's fractionally more difficult to explain to the public, it doesn't get the same attention.

author: BradC
author_rank: Super Contributor
timestamp: February 20, 2015, 12:50:07 pm
content: Quote from: AndyC_772 on February 20, 2015, 12:26:22 pmOddly enough the Australian and New Zealand governments get it..http://www.energyrating.gov.au/about/other-programs/meps/

author: hamdi.tn
author_rank: Frequent Contributor
timestamp: February 20, 2015, 12:58:34 pm
content: sure it matter, maybe not at individual level ( for the same reason AndyC explained, you may not care about so little consumption compared to what you actually use) but at national level it does ...

author: Tepe
author_rank: Frequent Contributor
timestamp: February 20, 2015, 04:35:47 pm
content: Quote from: hamdi.tn on February 20, 2015, 12:58:34 pmA small percentage for each individual adds up to a small percentage on the national level...

author: DmitryL
author_rank: Regular Contributor
timestamp: February 20, 2015, 05:41:53 pm
content: Quote from: dexters_lab on February 19, 2015, 02:44:06 pmWhen calculating something on "national" scale, usual arithmetics doesn't apply, imho.When this "energy vampires kill our mother-earth" bullshit started about 5 years ago and some nuts at work felt very excited about swithching numlock LED on keyboard in order to save power, I suggested them to calculate power losses in the mains because of the bad power factor of their computers' PSUs and compare it to the standby losses.. No one did anything smart about this fact

author: wraper
author_rank: Unknown
timestamp: February 20, 2015, 05:42:21 pm
content: Quote from: Tepe on February 20, 2015, 04:35:47 pmSometimes a few percent makes a big deal - is small margin company profitable or goes bankrupt over time. Often small percents in many areas adds up to the huge numbers. On country level few percent is a big deal, like country economics growing or falling.

author: Kevin.D
author_rank: Frequent Contributor
timestamp: February 20, 2015, 06:00:20 pm
content: I think this matters, Certain things can use a significant amounts of power when in standby or doing nothing usefull. A quick test on my wireless modem when not being used with a power meter shows it using 11.2 Watts continuously, doesnt sound much but over time it adds up, thats 98 kWh per year. At 20per kWh (average price per kWh in uk) thats £20 a year for a wirless feature thats very occasionally used (all my pc are connected by ethernet.) My pc related stuff (pc/monitor/printer/speakers) all came in another 10.3 Watts when in standby so theres another 90 kWh/year . I tested my tv in stanby,it shows 9W theres another 80kWh/year. thats 270kWh on just those few things (~ £50).These ones are probably among the largest wasters but theres loads other stuff I could have checked that are usually left on standby microwave,clocks,tvbox etc but you can see it's already quite alot with the few things I did check. This mutliplied many millions of times in each house, thats a few power stations worth of needless output, all because of poor design decisions to shave a few cents on manufacturing cost.heres a recent list from ecotricity of standby running cost of a few common items they tested .(based on 19p per kWh I think )Wireless Router (e.g. BT Hub) - £21.92Printer (Laser) - £18.26Set-top (Satellite) - £18.26Amplifier - £12.18Compact Hi-Fi - £12.18iPad charger - £12.18Nintendo Wii - £12.18Set-top box (Freeview) - £7.31Alarm Clock - £6.09Microsoft Xbox 360 - £6.09Modem - £6.09Sony PlayStation 3 - £6.09Air freshener plug-in - £4.87CD player / Tuner - £4.87Television (Plasma) - £4.87Video Player - £4.87Inkjet printer - £4.26Desktop PC - £3.65Nintendo DS - £3.65Oven (Electric) - £3.65Microwave - £3.04Television (CRT & LCD) - £3.04Mobile phone charger - £2.44PC monitor (CRT) - £2.44Electric toothbrush - £1.22Childs night light - £0.73 .regards

author: Mechanical Menace
author_rank: Super Contributor
timestamp: February 20, 2015, 06:27:17 pm
content: Quote from: Kevin.D on February 20, 2015, 06:00:20 pmBloody hell. My wireless router's PSU can't even supply half that much power.QuoteAnd hearing that makes me feel even less guilty at using about 4 times that leaving my PCs turned on just in case.

author: SeanB
author_rank: Super Contributor
timestamp: February 20, 2015, 06:32:34 pm
content: I also looked at this, so unplugged the TV set years ago as it was not being watched. Microwave over is the good type with a mechanical timer, so no standby power use ( interesting fact is the clock on a microwave typically uses the most power overall, as it is on all the time) there.Years ago ( in the 1990's) I started to use more efficient lighting, starting with PL lamps and iron core ballasts, and then using HID lamps along with 2D lamps. I used CFL lamps when they were $20 items, and I repaired them when they failed, and the first ones were made so you can replace the lamp at EOL, using a standard PL lamp.As an aside, one street lamp burning during the day is about the same power use as 200 households of cellphone chargers left on. Which one is reported more.......As an aside I got the metro bill today. Electricity is not the most expensive item there, neither is water. If you are not overtly wasteful you can easily use less power, and insulation and management is cheap and easy to do.

author: hamdi.tn
author_rank: Frequent Contributor
timestamp: February 20, 2015, 10:45:11 pm
content: Quote from: Tepe on February 20, 2015, 04:35:47 pmtrue but that national percentage is a 10 digit number when translated to $... usa as example 150 million house , with 270kwh per year per house that's around 40Twh/year

author: Howardlong
author_rank: Super Contributor
timestamp: February 20, 2015, 11:24:25 pm
content: My favourite treatise on this subject is the book "Sustainable Energy without the Hot Air"http://www.inference.eng.cam.ac.uk/sustainable/book/tex/sewtha.pdfwhere the author empirically calculates the energy used by us all in the many daily tasks that we do.In it, many issues are covered but, from an environmental perspective, the author compares the unplugging of devices in standby to bailing out the Titanic with a teaspoon. However, to be fair the point is that we ought to be mindful of the energy, and not simply discount it, but there are commonly much bigger fish to fry.For example, there it is a perverse absurdity to drive your car a couple of miles to your friend's house for dinner, and then take the opportunity to boast about your green credentials and the amount of energy you save by unplugging your phone charger.

author: langwadt
author_rank: Super Contributor
timestamp: February 20, 2015, 11:32:42 pm
content: Quote from: hamdi.tn on February 20, 2015, 10:45:11 pmbut some of them will need to heat their houses so the standby is not wasted, it is offset by the need for less heating

author: Howardlong
author_rank: Super Contributor
timestamp: February 20, 2015, 11:37:50 pm
content: Quote from: langwadt on February 20, 2015, 11:32:42 pmIn the winter, perhaps, but electricity is an expensive way to heat your home. In the summer, no, especially if you have airconditioning!

author: ConKbot
author_rank: Super Contributor
timestamp: February 20, 2015, 11:52:28 pm
content: Quote from: Neilm on February 19, 2015, 07:53:42 pmTake notice when items have a very hard to reach but still present mechanical power switch, and a "standby" button on the front. I.e. the Playstation 2, with a power switch on the back, along with the button the the front."Does it draw < 1W when its off?" 'YEP, draws 0W when its off, see, mechanical power switch'

author: AG6QR
author_rank: Frequent Contributor
timestamp: February 20, 2015, 11:59:14 pm
content: Quote from: Howardlong on February 20, 2015, 11:24:25 pmYou beat me to the quote, but I'll link directly to the page, anywayhttp://www.withouthotair.com/c11/page_68.shtmlAll the energy saved in switching off your charger for one day is used up in one second of car-driving.The energy saved in switching off the charger for one year is equal to the energy in a single hot bath.So if we're excited about cutting out our phone chargers, we should be equally excited about figuring out a way to eliminate six minutes of car driving per year. And if we make a half-hour round trip by car to the hardware store to pick up a switchable power strip in order to switch our phone charger off, the car trip alone used up about five years worth of the savings, before we count the embodied energy that was used to produce the power strip.Sure, every little bit helps, but little bits help only a little, while bigger things help more.There is a lot of very good information, well presented, in that book.While the standby power from little switching phone chargers is pretty minuscule, that's not necessarily the case for all devices that remain plugged in 24/7. In particular, some cable TV or satellite receivers /recorders can use as much as 50 watts while in standby mode, though most aren't quite that bad.http://www.popsci.com/gadgets/article/2011-06/least-electric-bill-murdering-dvrs-every-provider

author: Unknown
author_rank: Unknown
timestamp: February 21, 2015, 03:16:45 am
content: Quote from: AG6QR on February 20, 2015, 11:59:14 pmI was going to say, that seems rather excessive.My desktop PC (Xeon X3430 with a Dell 30" UltrsSharp monitor) consumes about 84 watts while running idle.My entire server rack (3 servers, 2 switches, and a few random bits) is currently pulling 328 watts with everything running.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: February 21, 2015, 06:27:35 am
content: Quote from: Howardlong on February 20, 2015, 11:24:25 pmTHIS.Numbers aren't hard, people!Quote from: dexters_lab on February 19, 2015, 02:44:06 pmThat's it? Considering there areover 7000operational power plants 1MW or larger, I would gladly build merely one additional Sisyphean unit just to make up the total!In reality, eliminating all those loads wouldn't even begin to amount to the excess capacity required to supply daily load variation, let alone seasonal. There is literally no way to account for and detect such a load; it's so deep in the noise as to be nonexistent.As an engineer, I would like to see the push towards higher efficiency devices. Lower standby will be a secondary result but not a primary focus. This has the added "benefit" of allowing product designers to choose whatever whacky molded plastic case they want: ABS is a pretty shitty thermal conductor, so every watt counts. Consider how hot your laptop charger gets at full load (charging the battery plus running the computer at 100% CPU): then consider the internal temp rise -- the transformer, capacitors and transistor inside the poor thing are probably 100C hotter than that!Between faster switching times, better capacitors and resonant topologies, most of the low hanging fruit is already solved; what's left? How about the input rectifier diode? That's another watt right there!The biggest problem is affording it; many things can be improved just by throwing better components at it. Customers will have to accept and indeed prefer a higher cost for their equipment if they wish to follow this path.Tim

author: madires
author_rank: Super Contributor
timestamp: February 21, 2015, 11:37:05 am
content: Quote from: langwadt on February 20, 2015, 11:32:42 pmAnd in the summer you'll have to turn your A/C a little bit up to compensate for the extra heat.

author: Galenbo
author_rank: Super Contributor
timestamp: February 21, 2015, 11:58:07 am
content: Quote from: dexters_lab on February 19, 2015, 02:44:06 pmAs long as Obama flies over his own team of cooks(and douzens other guys) because he doesn't trust the (carefully selected and monitored) cooks of his own USA embassy in central-europe countries (with their already own and monitored food supply)...And hundreds of similar stories.It Does Not Matter.

author: Mechanical Menace
author_rank: Super Contributor
timestamp: February 21, 2015, 03:06:37 pm
content: Quote from: mojo-chan on February 20, 2015, 10:41:36 pmDIR-615, and yeah it has a 4 port switch built in and the range isn't that bad. It's range is better than the one my ISP supplied and that's rated for 12W. Though it doesn't have a USB port (and I've got to admit I've never found that useful as anything but an ad-hoc phone charger) so that probably helps keep the power down.

author: Ice-Tea
author_rank: Super Contributor
timestamp: February 21, 2015, 03:18:22 pm
content: Yes, it matters. The difference between 0.1 and 0.3W standby is a big "meh", but having half a dozen old style trafos around the house *does* present a cost. In addition, my DSL router, setup box, NAS etc all consume considerable amounts of power. In many cases, this is all because of sloppy or at least very cost sensitive engineering. So a little incentive (ie laws/directives) on the other end of the scale does a world of good...

author: madires
author_rank: Super Contributor
timestamp: February 21, 2015, 05:16:26 pm
content: If I got 10 devices, each using 5W in stand-by mode, I'll pay EUR 100 per year for that. If I buy some switchable power strips to eliminate the stand-by power, I could buy a Rigol DS1054Z with the money saved in 3.5 years. That's a no-brainer!

author: langwadt
author_rank: Super Contributor
timestamp: February 21, 2015, 05:25:21 pm
content: Quote from: madires on February 21, 2015, 11:37:05 amthats like being concerned about wasting a drop of water while you are watering your garden with a firehose

author: wraper
author_rank: Unknown
timestamp: February 21, 2015, 05:54:37 pm
content: Let's view standby power from another point. Probably it is just few percent of total power consumption. However it is significant part of the energy saving. Household do have many devices: TV, computer, light bulbs, dishwasher, refrigerator... Well, when you decide if buying LED or CCFL backlight TV, you think - nah I take cheaper CCFL, I'll probably save less than 5% of my energy bill with LED one. The same with light bulbs, refrigerator an all other stuff. However if all those things were bought with energy saving in mind, your energy bill could be 2-3 times smaller. So how should you decide particularly which part of this energy saving stuff is insignificant, while all this small stuff when added together can make a difference of multiple times of total power consumption? If you consider every tiny part as insignificant, then you do not have energy saving at all and country will need 2x+ of power stations.

author: wraper
author_rank: Unknown
timestamp: February 21, 2015, 06:03:48 pm
content: Quote from: mojo-chan on February 21, 2015, 05:50:02 pmMy TP-link Archer C7 have 12V/2.5A PSU, yet consumes only 2.5 - 4.5W in different usage scenarios. Likely this is for external USB HDD and similar stuff.Quote

author: Mechanical Menace
author_rank: Super Contributor
timestamp: February 21, 2015, 06:09:09 pm
content: Quote from: mojo-chan on February 21, 2015, 05:50:02 pmWouldn't surprise me if the (very unfashionable) external antennas help a lot with that. The internal antenna also seems a little better quality than your standard PCB affair too.EDIT:I'm also not using the standard firmware, before I dropped that it was a bit crap.

author: madires
author_rank: Super Contributor
timestamp: February 21, 2015, 06:17:46 pm
content: Quote from: langwadt on February 21, 2015, 05:25:21 pmWe're collecting rain water from the roofs to water the garden. A m³ water inclusive sewage is about EUR 8 over here.

author: SeanB
author_rank: Super Contributor
timestamp: February 21, 2015, 08:20:53 pm
content: I don't have to collect rain water, seeing as about 50mm fell this evening between 4pm and 8pm.