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Standby TVs Waste Electricity, How About ACPI?
twitter asks: "There's power management and there's standby, do you know the difference? The BBC is running story on how much electricity is wasted by TV standby mode. Thanks to the very useful EnergyStar program, I'd be the one in seven who thought they were saving electricity, with the standby button. I've been very happy with APM and hibernation on laptops, and want to do something similar with the desktops I use. What's the state of APM / ACPI Wake-on-LAN for Linux these days?" Slashdot touched on this issue, earlier in the week, but that article was more on TVs, not on computer power saving technologies.
While the vanilla version works basically, Suspend2 is a more complete implementation. I use it on my laptop regularly.
Escher was the first MC and Giger invented the HR department.
WakeOnLan is basicly a matter of sending a 'magic packet' to the MAC address of the comuter you want to wake up. There is no need ofr the OS on that machine to actually support that functionality (except for there being a few cards around that require WOL to be re-enabled after each boot).
Sending the 'magic packet' is not difficult, and there is a variety of tools that can do this, including a ready made perl script, on a gentoo system, type 'emerge wakeonlan'. I bet it is available with most other distributions as well.
It's a fallacy to point out the total energy used by such TVs.
It's not a fallacy. There isn't just one of those TVs, there are hundreds of millions of them. They all use energy. Legislative mandates for more efficient electronics would go a long way. Right now, efficiency is simply not a criterion the manufacturer even attempts to optimize when developing a power supply; cost is a much, much bigger factor. This obviously needs to change.
Are you basing that on anything but intuition?
Don't be childish. If you take money out of your bank account at an exponentially growing rate and never put any in, it will run out in only a few decades. Regardless of how much is in there initially. Considering that energy use is growing exponentially, 50 years would be the upper bound for a shortage. I'm willing to bet on 10-20 before energy prices go up a LOT. Not like going to $2.20 per gallon for gas instead of $1.20, more like $20.00 per gallon. If this is to be avoided, the exponential growth has to be stopped.
It's amazing how quickly you learn to understand and control your energy usage when you're running off battery banks replenished by PV panels and wind turbines.
Every watt, volt and amp becomes precious, which means you must be aware of what is consuming how much and when.
Cooking and heating is done via as and intelligent construction methods, such as efficient use of insulation. Water gets heated via a thermosyphon, which works very well, even though I'm in an alpine environment (6,200' asl).
The only things I've given up are electric hotwater heating and clothes-drying, plus one or two other very heavy load devices. I still have my computers, stereo, and basics such as light.
Getting raw ethernet frames, in Linux, is trivial. For example, to get such a socket from python: (copied from the scapy startup routines)
self.ins = socket.socket(socket.AF_PACKET, socket.SOCK_RAW, socket.htons(ETH_P_ALL))
Whats that? You want to only get the traffic from a certain ethernet card, or want to transmit out a certain card? Easy. (In C, from my own code.)
struct sockaddr_ll device_sa;
int filedes;
filedes = socket(AF_PACKET, SOCK_RAW, htons(ETH_P_ALL));
device_sa.sll_family = AF_PACKET;
device_sa.sll_protocol = htons(ETH_P_ALL);
device_sa.sll_ifindex = ifindex;
bind(filedes, (struct sockaddr *)&device_sa, sizeof(device_sa));
You can get a device's ifindex with the SIOCGIFINDEX call, or with the rtnetlink RTM_GETLINK request.
All you need for this is root, or suid root. In fact, I think you can just use CAP_RAW and CAP_NET_ADMIN, I believe.
fnord.
Contrary to popular belief not everyone in the US owns a gas guzzling SUV... In fact my american car (Chrysler) gets better MPG than the subaru you mentioned.
As for everything else...
I did change my light bulbs, the effect I have to say seems negligable... Either my power company doens't bother to look at my meter to figure out energy use, or my lighting costs are fairly low and therefor the change made to small a difference to notice...
I don't have solar panels used for hot water... My house is already built (& I didn't build it), so the cost to change things now is to much for my fairly average salary to cover... I could try to get a loan to pay for it, but that would nuke any savings I'd see for years... I also doubt anyone would give me a loan... Winter would also cause some issues for this... Heating bills are largest in the winter and solar isn't very effective in general when the solar panels are covered in snow...
As for wind.... That's not a change I can make... Even if I did live in a good area (& I think winter would kill any effective use where I live), I'm not likely to be able to put up a tower... First their is the money issue again... Then I think my city would probably frown on it to... When I looked into wireless internet options I found out my area is heavily restricted on building anything over 30" tall... Less would probably not be so good with the number of trees around here...
Nice ideas, but practicality is questionable...
we are all invisible unless we choose otherwise
I've been trying to get power management to work on PCs for over a decade now, and we're still not there...
S1 (aka. sleep) works on most every system, since it's been around forever, but it'll only save you maybe 2% over the system being normally up and running (doing useful tasks).
S3 (aka. suspend) is the damn-good one. It only uses about 0.5 watts more power than your computer being completely off (I suppose it might be different with a more effecient power supply like a Seasonic). However, it's damn near impossible to get it to work. Windows XP, Linux, FreeBSD. Tried on dozens of completely different machines, and I've never seen it work, once. The drivers for pretty much ALL the hardware need to be written with APCI in-mind.
Hell, if I could just find a list of the motherboards, soundcards, and other components that have drivers on FreeBSD6 that will resume successfully from S3, I'd put together a couple systems with just those componets. Electricity in CA isn't cheap, and I'd be saving lots with instant-on from S3. No more boot-up waits, no more opening-up the same apps every time, etc. Just hit a button, and start working (as soon as the monitor can warm up).
S5 (aka. hibernate) writes out RAM to disk, and reads from disk upon restart. I'm not a particular fan of this method, as it would take quite a while to resume on a system with a large ammount of RAM. Still, it has the potential to be even lower power provided you're going to be away long enough.
So, in my experience, you're still screwed... Just shut-off the machine when you're done.
Slashdot gets worse every day... Pipedot: News for nerds, without the corporate slant
Same here. But they have both ACPI and CPU frequency scaling (aka centrino, powernow, longrun, longhaul) enabled.
The reasons are fairly simple.
There is only one case where power management is unnecessary. It is if you are running a computational load which requires your servers to work 365x24x7 flat out. Running without ACPI and cpufreq (if supported) for an average corporate or ISP load is plain stupid. It results in a less reliable server installation.
By the way, do not worry, 99.99 of the server sysadmins out there join you in this stupidity. In fact I did 7 years ago when I knew less about server administration.
Baker's Law: Misery no longer loves company. Nowadays it insists on it
http://www.sigsegv.cx/
Well, it's darn easy to get one of those timer switches + powerstrips/adapters with multiple sockets. Connect the equipment that don't need power (TV-set, non recording dvd-player, etc set-top boxes) all the time and program it turn off devices at least based on your habbits when not watching (like overnight, the time in work/school etc.). Connect devices losing clock and doing recording directly to power. Leave the timer easily accessible to be able to override toggle.
I've had this kind of setup past 4 years, the timer is leftover 20+ years old Theben Timer, still works perfectly and it takes only about stretch a day to reach the timer behind TV-set when back from work.
It's not a fancy high-tech solution but cut's standby waste easily 30-60% (estimate of hours not spent watching or turned on), which was enough for me to implement it. It's not huge savings here per person/family, but accumulated total for a nation it's quite a bit, like the BBC article claims.
Cheers,
ps. IMHO, it's oversimplification to claim that it does not matter trying to save excess power
consumption if you have thermostatic control or have electrical heating. It assumes that
all energy is equal in all ways which it isn't. The production price of power fluctuates and
is very much expensive on peak hours. The heating peak need is usually overnight, AC:s
cooling peak is afternoon etc. Lowering the peaks will lower the need of reserve kept. The
idea of avoiding all unnecessary consumption pays off in many ways globally and nationally.
I haven't checked, but I suspect he also leaves his TV and amp on standby.
I don't know what model TV you have, but if I unplug mine to get it out of standby, I lose all the programmed in channels and settings. Next time I plug it back in I have to reprogram it all. Same with my reciever.
No thanks, it's worth the $1 a month.
Some things I've tested recently:
My PC speakers use 40 watts, even when "turned off". Result: they're on a power strip with a switch.
My HP Laserjet 2100N uses 12-16 watts (depending on the fan), when in Power Saver. Result: it gets turned off when not in use.
My PIII-650 desktop server consumed about 50 watts when idle. Result: replaced it with a Toshiba Tecra PIII-650 (with a broken screen, cheap on eBay), which draws 14 watts when idle.
I also realized that my Powerbook power supply consumes less than 1 watt when plugged in but no laptop is connected, or about 2 watts when the laptop is plugged in and fully charged, so I'm not as concerned about unplugging it anymore.
My next checks: the TV's, older transformer-based clock radios, wall warts and the deep freeze. I will also take running "baseline" checks of my major appliances (fridge, furnace, washer), so I can recheck them once a year and identify when an appliance is running too hard (bad motor bearing, etc.)