Slashdot Mirror

X10 is [...] heavily unreliable. The modulation scheme hasn't been revamped in decades to take advantage of modern ECC schemes (which are no longer computationally expensive).

They could have had great success with an "X10 version 2" with a more robust ECC scheme and larger address space

They did revamp X10 to some extent, and called it A10. No doubt engineering has long surpassed X10's decades-old approach, but few other standards are affordably anywhere near mass market and "FLOSS-friendly".

However, 2-way communications only shine where the return channel provides useful information such as the position of blinds or the power consumption, ambient temperature or brightness at the remote location where a device has been switched on (and all of these sensors, or a simple standard plug or screw terminal to wire the latter two as appropriate, should only add about a dollar combined to the cost of making the modules).

Sure, but mind you, I have electric baseboard heating, which means it's 240 V, 15 A resistive load, not the regular 24v line you're used to with furnaces.

TH115, this thing is awesome. If you can stay with AUBE, they make good stuff, they might have some good 24v ones too. I can't find their main website, looks like they may have been bought by honeywell recently, or something, but anyhow, the model I have has three modes:
A - Ambient Temperature Mode
F - Floor Temperature Mode
AF - Both Ambient and Floor temperature modes (Allows heating to a certain ambient temperature, while putting a cap on floor temperature).

Pretty advanced little buggers, very reliable. Nice backlight on it. Tells you what percentage of power they're supplying to the heaters at any given time.

31W in standby, for just PC + LCD? I wonder if there was other stuff plugged into the same power strip that he was measuring, like cable modem, router, powered USB hub, powered speakers, etc. LCD monitors seem to vary more than PCs but most are around 1W in standby. On the other hand, my big LCD TV (with built-in HD tuner) does draw something like 45W in standby so maybe he has some crazy inefficient TV+monitor like that. (I use a smart power strip to control that monster.)

I noticed that those intelli panels have UK plugs or something and wondered if there was a US version. There is. It looks like the same people that make the Kill-a-Watt power meter have the same type of power strip here.

I have two computers and a couple of Kill-A-Watt meters, so here are the power consumption figures for my two home computers just for comparison:

My most power efficient computer at home is 1 year old and has a 1.83 GHz Intel Core 2 Duo processor, 2 GB of RAM, Windows XP and is hooked to a 20-inch LCD flat screen monitor. Not counting the monitor it uses 24 Watts. The 20-inch flat screen. monitor uses 40 Watts (or only 1 Watt when in the sleep mode). This is not a laptop computer, it is a very small desktop computer, but it does happen to have a very small motherboard which is normally used in laptop computers.

My other computer is hooked to the same keyboard, monitor and mouse through a KVM switch. I had room for more than one computer but not more than one monitor.

A 2-year old AMD-64 computer running Kubuntu Linux is my main computer, which I am using at the moment. It is a dual-core AMD-64 4200+ and is hooked to the same 20-inch LCD flat screen monitor. It is using 82 Watts at the moment, plus an additional 40 Watts for the monitor. It can use more power under heavy load. When the monitor goes into the sleep mode it's power consumption drops to only 1 Watt. The computer has 2GB of RAM and 2 large hard drives. It has a 380-Watt 80+ power supply that is over 80% efficient. I use Kubuntu 7.10 Linux and by default it has the AMD-64's Cool n' Quiet feature enabled which saves power by dropping the CPU's clock speed from 2.4 GHz down to 1 GHz when the computer is idle or not doing anything difficult.

By the way, it does use 7-Watts even when it is turned off.

• Kill-A-Watt meter
• What is an 80 PLUS power supply?

That must be one monster, power hungry, computer to use that much power when idle with the monitor off. I suppose that would include the power that you air-conditioner uses to remove the computer's heat from your home. I seem to recall hearing that it takes about as much power for your A/C to remove the heat generated by appliances as what the appliance itself uses. So during the summer we could probably just double the actual power consumption figures of your computer.

If you had a Pentium IV with a power-thirsty high-end video cards with a cheap, inefficient power supply, it might possibly use as much as 250 or 300 Watts when idle (I don't know for sure). I don't know how much you are paying per KWH, but even including the effect on your air-conditioner, I would guess about $50 per month at most, for one computer, if I am calculating that correctly.

My computer probably uses less power than most desktop computers. It is plugged a Kill-A-Watt electricity usage monitor, at the moment, which shows that I am using 82 Watts (not counting the monitor). My LCD monitor uses an additional 38 Watts, but only uses 1 Watt when in the sleep state. If I left it on at night the the monitor would be in the sleep state using only 1 Watt. I also have a UPS, speakers and a few other things not on the meter so lets just round it off to 100 Watts.

A pay about 14 cents per KWH for my electricity where I live. If I am calculating this correctly, that would be about $10 per month. During the summer, I could probably call that $20 per month, if I include the added load my my air-conditioner. I hope I calculated that correctly, including the conversion from Watts to Killowatts and canceling of the units. Perhaps, some engineer or math geek could check my math. Here is my $10 per month calculation:

(100 W / hour) * (1 KW / 1000 W) * (24 hours / day) * (30 days / month) * ($ 0.14 / KW) = $10.08 / month

Kill a Watt EZ Electricity Usage Monitor

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

I switched to more energy efficient computer hardware, but did not just suddenly go out and buy new computer hardware all at once. I waited until each item became semi-obsolete or quit working, then I replaced it with a more energy efficient replacement. Perhaps the author should have suggested that people do it that way.

There are other advantages besides just saving money. For one thing, during power failures, my computer can now run much longer from UPS power. There is at usually least one thunderstorm, every summer, which knocks out the electricity for an hour or more. There are also usually other thunderstorms that are so loud and close, that I pull the power plug and unplug from the Internet, to avoid damage. I can now keep on working longer from UPS power while waiting for the worst part of the storm to pass.

An energy efficient computer is also usually quieter, because less powerful fans can be used.

With my purchasing choices as a consumer, I am sending a message to manufacturers that energy efficiency counts. I do not want a 500Watt power supply and dual power hungry high-end video cards. By purchasing energy efficient products, I am telling them that I want good performance with minimal power consumption.

One thing that the author did not mention was 80 PLUS certified power supplies. They are much more energy efficient that many of the other power supplies. I used one of those when I built my latest computer from scratch. Like the author, I also use a Kill-A-Watt meter. I also save energy by using CFL light bulbs.

I hooked up a Kill-A-Watt meter to my monitor again, just now, to see for myself if dark colors save power on my monitor. In the past, I had noticed that my 19 inch CRT monitor's power usage varied from 64 - 84 Watts depending on background color. With the CRT monitor, the dark color used about 20 Watts less. In the sleep mode, when the screen was blank it only used a little over 1 Watt.

My new monitor is a 20-inch Dell 2007FP flat panel LCD monitor which I will test right now. With Firefox running under Linux, I have Blackle.com open in one tab and Google.com open in another tab. Looking at the Kill-A-Watt meter, I get 35 Watts for Blackle.com and 37 Watts for Google.com. So using a dark color on my 20-inch Dell 2007FP flat panel monitor only saves 2 Watts. In the sleep mode, when the monitor goes blank, it only uses 1 Watt.

Oddly enough the power consumption on both my monitor and the rest of the computer varies from day to day by about 3 Watts. I am not sure if that is due to variations in room temperature or the daily variations in the voltage of the electricity that I get from the power company or what. At the moment the voltage here is 124.5 volts, sometimes it has been about 118 volts. The power company has come out twice, in the last decade or so, to adjusted the transformer on the nearby power pole to raise or lower the voltage.

So anyway, Blackle.com only saved 2 Watts on my 20-inch LCD flat panel monitor, which is not very much compared the the 100 Watt light bulb that is on in a nearby lamp. Just in case you had to ask, according to the Kill-A-Watt meter, the 100 Watt light bulb in one of the lamps is using 100 Watts and the 100 Watt light bulb in the other lamp is using 94 Watts. Switching to a more efficient type of light bulb would help much more than using Blackle.com.

• Kill A Watt meter
• Dell 2007FP 20-inch Flat Panel LCD Monitor

things.
If you put your TV in the control socket then presumably when you turn the TV off (or put it on standby) it would completely power down whatever other items you have in the switched sockets and there are constant hot sockets for your PVR and whatever.
It's not exactly what you described and wouldn't shut off the TV standby power. On the upside it wouldn't give you another remote control to keep track of!

Around here you can buy power strips with a special "TV" socket. Plug the TV in the TV socket, and the rest (DVD etc.) in the other sockets. As soon as the power strip detects the TV using less than 20W, it powers off the other sockets. At least that way it's only the TV on stand by.

Is this the one you're talking about? Looks like a good solution, from what I can tell; I'm intrigued. Combine that with using compact fluorescent lights instead of incandescent light bulbs as possible, and you can significantly reduce your home's electricity consumption.

1) Presumably you've looked into 'home automation' and suchlike? I've never used it, but I understand there is a home automation standard known as X10. A quick search for "X10 HVAC" reveals there's a few about.

2) You talk about VNCing in from work. A system that needs a PC on 24/7 probably won't lead to a net energy saving, since your computer is probably consuming more than 100W any time it's on. If you would have your computer on anyway, consider turning it off and getting a $10/month shell account somewhere for your server needs - that may well represent an overall saving for you.

3) Captive tappets rock my world. No stupid digital timer with a tedious 3-button interface, and much better than most other designs of mechanical timer. Not that appliccable to your needs, I know, but I thought I'd mention them anyway.

4) Get a radio-controlled system! I always thought they were a bad idea since you have the bother of batteries, but as I recently discovered, it means you don't have to mount the control unit anywhere, meaning you can keep it right by the door, or on a convenient shelf. Beats going into some upstairs cupboard to set things up - especially if you're changing it regularly.

Michael

Eh???
Does "world's first" now mean "one of hundreds, developed anytime within the last 10 years?"

What about Lightstat's i-stat, the Internet Thermostat
or perhaps the Shell Home Genie system
or perhaps ProAction's industrial system
or perhaps just go google and pick one of your choice...

• SmartHome
  
• PCS
  
• Leviton
  
• ACT/Smart Products
  
• Lightolier
  

You mean like this one?

I got one for $25 late last year at the Brookstone outlet in North Conway, NH (all Brookstones have them I think, but for $100).

I played with it for a few minutes -- voice training was quick and easy (I think it can recognize 3 or 4 people, assuming each trains it), supports macros and multiple devices (but alas, doesn't learn). Seems like a decent toy for average, mid-range stuff, but doesn't know how to talk to my ReplayTV (maybe not an issue soon, but it doesn't know TiVO-speak either) -- I just haven't had time (or desire) to program it completely, as my wife pretty much has taken over that room and seems uninterested in voice remote, despite the fact that she still juggles 5 remotes and won't even use the already-programmed yamaha universal remote that came with my receiver. Heck, she won't even enable the surround for TV most of the time (unless we're watching a movie and I insist) -- she uses the horrible TV speaker and seems fine with it. Sigh.