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Electric Company Using Power Lines for Data
Snags writes: "The local electric company PPL Utilities is testing a system to send electricity usage readings back to the company over its own power lines. According to a local newspaper article, they are using the TWACS system made by DSCI. I'm just hoping this doesn't interfere with other ideas for sending data over power lines."
Boy, I can't wait for the first time I can take a tcpdump of my electrical wiring in to dispute my bill...
:)
And how about a DDOS attack? Do I have to firewall off my toaster now?
this idea has the potential (get it?) to make a short in your network card a little more hazardous. This is a BOFH moment waiting to happen.
One CPU cycle wasted on digital restrictions management is ONE TOO MANY.
A proposal to use power lines in the UK for data transmission was dropped because of a number of difficulties, most notably the fact that HF radio (about 2MHz to 30MHz) would have been rendered unusable in urban areas. Street lamps made great quarter-wave antennas.
In ohio, they are doing this in several place,
In a small town (where I work) they have pretty progrewssive ideas on power and communications,
First they have community power, almost 1/2 the cost of Ohio Edison in the next town over. Second is community cable, once again much cheaper, third is cable internet access, $20 a month compared to Time Warners, which you can still get here,
NOW about a year ago Wadsworth put FIBER to every home in wadsworth, long term plans include long distance. AND the ability to selcetivly shut down electical stuff on peak demand, (just your air conditioner, etc) to avoid brownout, because of the above reasons , and one of the best public school systems in the country, population is exploding.
Wadsworth is a great town and I lived there during my high school years, BUT If i lived here again an axe and cutters would hit that fiber so fast it'd make your head spin. Shutting down services on your panel selectivly MY ASS.
Sig went tro...aahemmm.....fishing........
I read in this article (Wired magazine... not on the web), the total corporate history and research of this project idea.
Basically, big ass companies like AT&T etc.. did a lot of testing and decided that it was just too expensive to offer net over the powerlines. The main problem was that although one could effectively transmit data over the powerline.. once it hits a transformer the data is lost, and the only solution that 3 big companies could come up with was a device installed on each transformer to carry the signal, which is completely uneconomical and defeats the whole purpose of using the existing powergrid.
There is even a big scandal with another company that claimed they could overcome this problem.. and it turned out to be a total fake, and lawsuits galore occured.
Of course there is no problem with using the powerlines in your house to network... so Rock on Lan parties!
The communication uses the zero crossings of the 60Hz waveform--same as X-10. Last thing I'd want is my lights turning on and off when they do meter readings.
bp
Many power companies have fiber up on the high voltage towers - which generally terminate in metro areas and rural areas at power stations - they use it now mostly for substation monitoring and internal networking. However, given the bandwidth potential of this fiber - they've got the ultimate backbone available. They just need to get that last mile figured out - no easy task!
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HydroQuebec, in the provinde of Quebec (duh!) tried this a few years ago (circa '97).
At the time, there were a number of obstacles that made this technology unworkable. If I remember correctly it had something to do with electromagnetic field sensitivity. The earth's EM and solar flares made the whole system too error prone, at the time.
This brings up another memory. A company, 10 years ago, had a cheap office wiring system that used the ground outlet as a network transport. With their adapter, any machine plugged (quite literally) was on the same network.
What made that idea (and company, I think) fold was the lack of security. Anyone could connect to your house's power outlet and get connected. Furthermore, there were no filtering devices that served as "firewall" between your house and the external power grid.
TWACS currently reads at 300bps. There's technology out there that will up that, but it isn't going to get anywhere near what's needed for a decent Internet connection anytime soon.
My husband has been working with DCSI for about 2 years on the system in NE WI and there have been a few issues with interference, but not with homes and shit. The pulses aren't strong enough to interfere with normal shit, though there was one incident of a substation - which sends time synch pulses out to individual meters - setting off the railroad crossing alarms every 15 minutes.
It's a better solution than using RF to transmit the readings back to the sub - most of those are using 900MHz to transmi and you can imagine what kind of problems THAT causes.
I don't have a solution, but I certainly admire the problem.
Our competitor got their hands slapped pretty bad by the public utility commission for that one and had to eat the entire investment. There was just no justification for such fancy toys to handle such a low-tech task.
sPh
This article gives no indication that signals over power lines could acheive any reasonable amount of bandwidth. Power lines simply aren't designed to carry information, and I'd bet there would have to be a lot of upgrading of the electric company's equipment to enable this sort of thing.
I would compare this technology to that of x10.com's wireless devices, which send very small amounts of data over house power lines. There's a lot of limitations to it... flourescent lights don't work with them, and the lack of shielding on power wiring sometimes causes devices to spontaneously turn on or off. (this happened to me with my bedroom light....it would turn itself on at 3am, very annoying).
When you hit the button to turn on a light, there is about a two-second delay. Considering that the remote is transmitting approximately 12 bits of data (4b house code, 4b device code, control bits), the data rate seems to be on the order of a few bits per second.
I'm assuming the power company is using a similar form of technology for data transfer. By the time (e.g. years down the road) a system could be set up to transfer a reasonable amount of data over a power line, access to cable/dsl/wireless internet should be advanced and widespread enough such that trying to transmit over power lines shouldn't even be worth the effort.
Of course....the concept of sending data where data shouldn't go is still pretty damn cool... 8-)
"If at first you don't succeed, lower your standards."
IIRC from my tour of a substation years ago, electricity suppliers use power line carriers (PLC) to communicate between substations to relay switching information. If you happend to be driving by a substation, look for these large cylinders called wave or line traps, that are used to "capture" the RF signals...Cool stuff especially since they are operating on something like a 500kV line. Probably a much simpler modulation scheme though.
"Karma can only be portioned out by the cosmos." -Homer Simpson
The high speed data over mains, as they are testing in the netherlands, has been shown to create massive disruption to radio services. It would take a real lot of money to bribe (lobby) the FCC/congress to allow this in the US, money which would be hard to raise considering the dismal state of the telecom industry.
The service indicated here seems appropriate for telemetry. I wonder if they have accounted for security in control situations though. It may be too easy for someone to forge a packet. Still, at 300 baud (or what that bps?) its interference problems maybe be far less.
We canned the idea for Internet, but this application sounds ideal; low bandwidth, low contention (presumably), and if it goes wrong, you can always send the legacy meter readers around in a van... Or you could upgrade all your kit, I wonder which one they'll opt for...
UNIX? They're not even circumcised! Savages!
There's very little in common. TWACS works by doing phase-shift modulation on the 60Hz carrier; this is a wonderfully robust method when implemented correctly, but at best you get a bandwidth of a few tens of bits per second. This is great for reading power meters (where a few bits per hour is plenty of bandwidth) but it has nothing to do with high-speed internet connections.
I was outside the house the other day and noticed that my electric coop had installed a new meter. Upon closer inspection I noticed a little red light on the meter. Curiousity was peaked so I called up a friend of my that works for the coop and he went into a long explaination about these new meters they are rolling out. He called them Turtle meters and a quick net search turned up http://www.turtletech.com/Products-Sales/standardt urtle.htm
To quote their website
It monitors kilowatt-hours and records peak and minimum demand. The data is time-stamped and is continuously transmitted across the utility's own power lines. As long as the meter has power, the Turtle transmitter can provide a count of short outages (blinks) and establish whether the transmitter is in power fail.
The Standard Turtle transmitter can be programmed to return one of eight different data transmission options. The time needed to transmit a complete packet varies from 13.9 to 27.2 hours depending on the amount of data being transmitted.
Which falls in line with my friend telling me that it can take a day to get a reading because they are using a super low frequency. So yeah, they can remotely read meters. But they have definite problems with lightning. My friend spends a lot of his time in the summer replacing the Turtle units in the meters because they fry very easily he says. But they are cheap enough that it is still cheaper than sending a meter reader to all the houses.
Hunt says they've been doing this since 1995, so its not new, but few people have seen it because it has taken a while to get them out.
I think my local power company (FPL) is using a two way version of this for their ON CALL system. This lets them brown out selected appliances in your house (such as your water heater or Air Conditioner) for brief periods during high power demand. You tell them which appliances you will let them control and they install a special box between them and the power line. They only brown 'em out for brief periods (I forget what the max power cycling periods are). For this you get a lower rate on your power bill. Makes sense for some people.
I live in Reykjavík Iceland, and the power company here has already implemented internet over powerlines, although only a few people are using it now it seems to work just fine.
I guess we can use this technology because the entire population is about 280.000 people (and about 260.000 of them use the internet) check out Fjöltengi even though most of you wont understand a word of that page, you can check out the pic of a chick using the magical-gadget on the main page.
Hitler's in the fridge.
Yes, they have been doing that for quite a while. I looked at the board design for a meter like that maybe 8 years ago, although finally the job of producing them went to the Tampa plant, since the customer was a Florida utility...
And this is redundant, but dozens of idiots still haven't got the message: It's NOT an internet connection. It's not even a 300bps teletype connection! Power lines are not built to carry signals -- but you can sort of make it work if you send just a few bits per second, with lots of error detection and correction coding, and ask for a repeat whenever a switch flips somewhere and drowns out a packet.