I’m happy with my LED lightbulbs

Yesterday I received the new LED lights I ordered last week. They are quite nice, very little power consumption, and they do quite a nice light. The 2W spotlight version I have in my bedroom now make as much light as a 25W incandescent lightbulb.

It sure isn’t the flood of light I had before, with just two fluorescent lights, but I didn’t want so much light in my bedroom anyway, it distracted me wile reading, and caused me not to sleep when I wanted to read something. The new lights give me a cone of light just on my bed, and keep the corners of the room in half-shade, which is a very nice visual effect, I have to say. There is enough room to cleanup and to choose my clothes day after day.

I’ve traded 2x8W fluorescent lights with 3x2W, so it’s a decent improvement in consumption too.

I also bought another one, spherical, true white rather than warm (amber) white as the ones of the bedroom, to put in the lamp on my office room. I used a bigger 20W fluorescent light before, it flooded the whole room with light. Now it only lits the area of the desk where I work, exactly like I wanted. The bulb there is less than 2W, which is quite a nice saving too.

I’ll be looking for some different kind of bulbs for the stairs though, as the opaque types I found on the eBay store where I bought these didn’t seem powerful enough to light my stairs properly.

But, for all the people skilled with electronic out there, I’d like to know something. Somehow the lights I have in my room lit up even when I turn them off. It’s not entirely bad for me as I actually sleep better with a minimum of light around, rather than in pitch dark. But I’m a bit concerned. I thought it was a condensator before, but it doesn’t uncharge even after a whole night, so I’m more thinking along the lines of a possible electric problem, like a wrong return line, or some problem with the grounding, but I admit i have o idea how to proceed. If I unscrew the light, it shuts down.

Also, the fluorescent lights I removed started being employed already: one replaced one of the stairs’ bulb, that was the last one in the house, now I can say that the whole house is powered by green lights, either fluorescent or LED.

LED lamps, part two.

You might or might not remember that the last post on my blog for the three weeks I spent on ICU was talking about mirror lights.

Well, my interest in LED light bulbs hasn’t disappeared yet, so a few days ago I decided to take a look to eBay to see if there are other similar LED lights to put on a desk lamp (I needed one in my bedroom to read something before sleeping without having the ceiling light on, which makes it difficult to get sleepy.

When I looked for LED lamps last summer, the only eBay shops carrying them were Hong-Kong shops, and indeed I bought them there (they arrived while I was in the ICU). When I looked the other night, the shops were mostly German instead. Nice change I’d say, although I can’t tell how this happened.

So I ordered four new lightbulbs, two of a “candle” type, and two spotlights. The (cheaper) spotlights have a reddish light, unsuitable for me to read (I react better to greenish light), but still nice, they would probably be good for either my mother or for big flashlights. The two candles instead are quite good, they make quite some light, and consume less than 2W. I put one of them in an old ceramic and glass desklamp my mother was not using for a while, and put it in my bedroom (strange effect such a classic lamp against the modern bedroom, but the light is quite good); they have a soft white tone, which makes it perfect to read before sleeping, and it’s enough light even to get to the drawers to get socks and company.

Not sure if LED technology improved this much while I was in the hospital, but at least I have to say that the LED lightbulbs are becoming quite interesting even for ceiling lamps. Who knows, maybe in a few years we’d be all saying “fluorescent lights? bah you’re not green enough!” ;)

Mirror lights

When you feel depressed for your personal situation, there are many things you can do to stand up again and don’t think about it. Myself, what makes me feel better most of the time is bricolage. Just making a new hole for a frame, or recabling a power plug, or changing the disposition of my room. Today, it was changing the ceiling light in my bathroom.

Let’s skip over the fact that my neighbour had a new ceiling light at home, and just focus on why I wanted to change mine: the previous one was quite small and a fluorescent light wouldn’t fit, and the bathroom was the last room in the house with an incandescent bulb. Well beside a couple of desk lamps that are never turned on.

I’m not sure if it’s a testosterone thing or whatever, but punching holes on the ceiling with a 18V battery drill is something that makes me feel powerful. Am I a freak? Probably.

Anyway what I want to hear others’ opinions about is about the lights of the mirror: right now it has two E14 screws, with just one 15W incandescent bulb in it, I used it mostly while shaving (as the 75W incandescent light on the ceiling wasn’t good enough) or when I didn’t need much lighting and this was a nice power saving. Now, the fluorescent light takes 20W, so I’ll probably just turn that one on, as it has better performances when compared to the amount of light, and it shouldn’t be much of an issue while shaving.

Even if the need for the mirror light is now quite reduced, it doesn’t mean I’ll never have to use it. Sometimes you need some more near lightsource to look for instance at a broken nail. It bugs me to have to use a 15W bulb for so little light. First I thought to replace the lights with some kind of halogen bulb, but even if those have way better performances, they still consume quite a bit. I don’t need so much light, I just need to reduce the power consumption.

Then an idea was in my mind: I have a sort of flashlight in a three-in-one tool (screwdriver and spirit level are the other two tools); the light tool uses a LED, supplied by a button battery, and has quite some autonomy. This convinced me that the best thing for my mirror lights would be a LED-based light system.

Now, do you think there are already kits to set up LED lights on a mirror closet? Are there LED-based bulbs that just need a socket and a controller? Are those 220V supplied, or should I decide for something battery-based? Any pointer and suggestion is very welcome.

Saving energy?

Disclaimer: I’m not an expert, my physics knowledge is limited to high school classes, and I probably forgot most of it already; what I’m trying to do here is apply some low-grade math to a few numbers that got inferred out of reading about active PFC supplies around the net when I discovered I needed a new UPS. It might be accurate, in which case I’m lucky and happy, it might be totally bogus, in which case I’d like to know what is wrong, and what the truth would be. Don’t take my words from granted, and if you can give some more in-depth knowledge to either agree or disagree with this entry, I’ll see to update it.

This is a stream of consciousness entry, as I was thinking if it was worth the investment of replacing the three other PSUs I have in my home office with with active PFC, now that the UPS is replaced with the new one that supports them.

I’ve read that the improved efficiency of these PSUs is between 5 and 25… Alessio told me that it can reach 40% trying to avoid hyped values, I’ll try to make some calculations counting about a 10% saving over the size of the PSU, so that a 400W PSU replaced with an equivalent active PFC unit would save about 40W.

Now, I have three boxes in my home office, one of which is Farragut, which is turned on 247, meaning 8760 hours in an year; the PSU should be around 300W, so with a 30W saving, I would save 262.8 KWh in an year, which would then cost me (assuming the price for the second range: 1801-2640 KWh/year) €/cent 13.65 per KWh, which would be about €36 in an year. Considering the price of an active PFC unit to be about €80, in less than three years, it would have been paid back for good; if we count with the highest price, it would be about €59, so two years and I’m already in active.

The other two PSUs wouldn’t save me nearly as much, let’s say they would save me €10/year, it would take me a few years before paying them back, but then, they would help me with the noise (Farragut’s PSU’s is the most silent beside Enterprise, the other two are quite noisy) and the heat they generate.

It’s not bad after all, and saving energy is an important task nowadays anyway. But I wonder, how much can be saved for instance in my old ITIS (High School)?

I know of at least six or seven “servers” that are old PCs with ATX cases and PSUs, when I left the school three years ago; considering their age I’d suggest an average of 300W each too. That would be about 2000W and thus 200W saved by moving to active PFC equipment. They would also be active 8760 hours in an year, as most of them are active even when the school is closed during the summer; it would be already 1MWh/year saved.

Then there are about 9 laboratories with an average of 10 PCs turned on for about 9 months an average of 6 hours a day (and more than half of that time, someone is playing on them); they are usually newer so I’d suggest a 400W average PSU, saving 40W each. The save here would be 5.8 MHw/year.

For sure the price of energy for a school is lower than it is for an house, but it’s still a huge amount of energy, and money, even counting 10 eurocents per KWh, it would be about €600/year, for a single school; I don’t know how many schools like this are present in Italy, but seems like to me they can be quite a big amount of energy waste, considering the abundance of cheap hardware in their PCs, and servers.

Now that I’ve done a bit of math, I think I can say that the European Union directive that forces the use of active PFC power supplies does have a sense, and I’m glad it was issued, even if it forced me to buy a new (far from cheap) UPS.

Suspending a PC

I’ve already written about my tries to use laptop policies on my desktop to be able to preserve my UPS’s battery runtime. Today’s focus instead is on Intel’s PowerTOP initiative, which is quite intriguing. I also remembered that Nokia decided to make more prominent the signal of charge completion on their new phones, so that users remember immediately to remove the adapter from the line.

Looking at this, I started wondering even more about my usual patterns when it comes to power consumption. I’ve started lately to shut down the multiple power cord I have where the amplifier and a few adapters are connected, when I go to sleep, but this has at least one problem (I can’t recharge the mouse this way), and still wastes the power consumed by the adapters when it’s day (and thus the amplifier has to be running), and I’m not using them. Attaching and detaching them every time is not really an option, as it’s quite difficult to get down to them, so for now this is a decent mediation between power saving and easiness of using the chargers.

To solve this I was already thinking, and now I’ve decided and just need to enact as soon as I get to make some shopping, to buy a new multi-plug, possibly with per-socket switches, so that I can avoid attaching/detaching the connectors, but still be able to disable what I don’t use, then I’ll attach it to the side of the table, so I can reach it easily without going under the table. This way I can just connect what I need and then remove it when I’m done.

Then there are the ATX power supplies, which still uses 5V for the wake up check; I shut off Prakesh every time with the switch, but that is because the ACPI on that box sucks and it doesn’t power off at all when I ask it to, but I don’t shut down Klothos because it’s difficult to do so.

But of course the main problem is Enterprise: being my workstation, I usually have it turned on most of the time; sometimes it’s building, sometimes it’s simply playing back a movie for me, but there are times when it’s totally idling, and in those cases, I should really shut it off. The problem is that often I have the four virtual desktops full of windows, browsing source code and Konsole sessions full of output I’m working with. Even with KDE’s session support, it’s not easy to return to such a point when restarting, the main problem being that the window gets misplaced, more windows are opened, and opening 10 different Konsole sessions ends up timing up the SSH/GPG agents, which then requires me to close and then reopen all of them, and I lose the output; Emacs also doesn’t seem to support save and restore of the session this way.

So I decided to look at ACPI sleep states: suspending to ram might allow me to just shut everything down, then restart the day after with the desktop exactly as it were. It’s like when I close the MacBook Pro when I’m on OSX, and that is nice.

So I look up what I need: kernel didn’t have ACPI sleep states enabled, so I enabled them, rebuilt the kernel and rebooted. Merged hibernate-script, and run hibernate-ram. The first try failed after 20 seconds, lirc_dev module disallows going to sleep. Bummer, especially since I don’t want to touch, or to contact the upstream of, lirc anytime soon (remember in the early 2.6 days when you had a kernel patch to get LIRC to work, rather than using drivers directly from LIRC? That patch was mine, unfortunately). No problem, remove lirc_dev for now and try again. It slept, and then it frozen after a few seconds from wake up. Maybe it’s lirc remaining half loaded, so I decided to remove it from the kernel directory and reboot. Nothing still freezes afterward.

Now I’m not sure exactly what it might be, and it’s too late to experiment, it might have been DynamicClocks I did just enable in X11 (after all I never use 3D, if there was a decent graphic card with only a good Xv driver, and nice Xinerama support, I’d be all for it), tomorrow I’ll check. Hopefully it will work, then I’ll just shut down Enterprise all the nights when I go to sleep, and wake it up in the morning (or in the afternoon) just when I need it.

I also started wondering about the kind of processes that are running in the background on my box even if I’m not using them: just in KDE there is KTeaTime, that I use when I need to remember to do something in X minutes, KBluetoothd (I use BT only to transfer data to the cellphone, and it’s rare), KOrganizer (okay this one I need more often), and a bunch of other stuff. Leaving them there ends up sucking CPU and power, thus causing more heat. In the background I have lighttpd, distccd and again a bunch of other stuff that I usually don’t use. I should actually start by stopping everything I don’t need and start it only when needed (if I’m not building on Prakesh or Farragut, I don’t need distccd; if I’m not printing I don’t need cups – and the Printer is now shared by the AirPort Express, so I don’t need it to share anymore).

I suppose that it would be nice to have something that actually starts a service only when it’s requested; inetd is probably the nearest thing you get for this, but I wouldn’t be surprised if it used low performance methods for waiting for connections (epoll should be better than poll on this regard, if I remember correctly; on FreeBSD instead there’s kqueue). I could also write a simple tool for starting/stopping services as I need them, without having to use a console to start mysql when I’m working on job stuff that requires it.

I’m also considering connecting the bluetooth dongle on the fly when I need to do a phone transfer; the problem here would be to have programs starting up when needed too (like kbluetoothd). It would certainly be nice.

So this long blog post might be just a start for a comments’ spree: what can software do to make sure we don’t run code that is not needed to be running? Smarter startups? Better bookmarks? Ideas?

Laptop policies on a workstation

As I bought the new UPS, I now have quite some time to work with it while I’m without power, as the two UPSes can keep the system online for about one hour without any kind of interruptions, included network access. This is quite nice, but there is one thing I was thinking of today…

When the workstations are running on UPS’s battery power, it’s comparable to a laptop running on battery, so I could be just using the same method laptops use: reduce the frequency of the CPU. At least Enterprise is able of CPU frequency scaling, so I’ve configured it to switch to power saving profile when the onbattery event is received by apcupsd.

It was actually quite simple, first of all apcupsd runs as root (although it should drop all privileges, but I’m not sure about it), and I have powersave installed and configured to handle this, so I just changed the /etc/apcupsd/onbattery and /etc/apcupsd/offbattery scripts to add a call to powersave binary, with -e Powersave on the onbattery event and -e Performance on the offbattery event; unfortunately I don’t think there is anything else beside slowing the CPU speed during UPS battery supply that can be done on a Workstation :(

Now I’m going to look to split the connection of the power cables in my home office so that the hardware that would just go in standby while I’m sleeping would be connected to a single multi-socket, which can be disconnected at once, to avoid leaving the hardware consuming power without any reason. I’d like to be able to do the same with the monitors (that otherwise would remain in standby as they can’t be shut down. If I wasn’t using the same UPS for both networking and monitors, I could probably use the UPS to shut them down and turn them back on at my command.

Sigh, I’m afraid there will be a looot of work to do, and I’m sealing envelopes, once again :(