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Broadband via Power Cables trials in Scotland
Wacko writes "Scottish Hydro-Electric have started a trial of Broadband internet access via power lines. Just plug the modem into any power point in your house, with no need for additional lines into the house, and reasonably priced too. Details are a bit scketchy right now but interesting to see how the trial goes."
The contractor bringing this to homes in North America is Current Technologies. They have a demo home set up with Pepco and will be doing customer trials this year.
Competition == Good.
The prices are reasonable, at £15/month + VAT, but that is subject to change at the end of the trial period (31 December 2003). The price appears to be this low due to a grant from the Highlands and Islands Enterprise, and the Department of Trade and Industry.
At the moment, availability for the trial is limited to Creiff and Campbelltown, Hopefully this will be extended (I live in Aberdeen - by no means Rural, but this would still be useful for me personally).
There is a form provided for users to register their interest in the service... Perhaps if enough people register, this service will be rolled out on a wider scale... Here's hoping...
Disclaimer: I meant what I thought, not what I wrote! What? You can't read my Mind? Oh dear!
http://computertimes.asia1.com.sg/v20020501/updt01 .shtml
Apologies to all those folks in rural America, but they're still screwed. Actually, this technology would be much more difficult to implement in the United States and Canada than in Europe.
The U.S. power grid typically delivers moderately high voltage to each little neighbourhood--a small handful of homes at most. At that point, there is a small transformer (a "pole pig"--no ethnic slur intended) for the last step down to 110 volts.
European grids usually step down to 220 volts, and do it further from the homes. There are significantly fewer transformers per capita, as each transformer serves more homes.
The problem is this. The high frequency data signal gets flattened out going through a transformer--those big coils act as a low pass filter that eats your data. You have to pick up the signal from the server before the high voltage side of the transformer and reintroduce it on the low voltage side (and do the same thing in the other direction for upstream signals).
In Europe this is not an insurmountable problem: you just need to hop over a few transformers in a handful of central locations. In the U.S., you have to install some sensitive electronics on every pole pig--exposed to the elements in a lot of widely separated, awkward to service locations.
Oh, and rural America has it even worse--some homes have their very own transformer, and would need their very own jumper for signals. Also, if there is a long enough length of power line back to the substation, the inductance of the power line will be enough to eat any high-bandwidth signal.
~Idarubicin
The biggest problem is getting the signal through the pole pigs (can-type transformers on top of the hydro poles) -- they are big iron monstrosities that don't pass much past 1kHz or so due to their design.
One method which can be used is to simply wire some high voltage capacitors across the primary and secondary of the transformer -- they'll conduct at high frequencies (you tune this) and voila -- your signal jumps the transformer.
Of course, the problem with that is you're no longer isolated from the street-line voltages -- anywhere from about 6.9kV to 44kV, depending on who else is in your neighbourhood. The "right" way to do it is to have a line-powered conveter box at each pole pig which jumps the transformer optically, but that's expensive.
I've always been a fan of power line transmission. There's one in particular I was always amused by (no link handy) -- they claimed that by using a maser they could modulate the magnetic field without altering the voltage and current. I wonder what they think of Maxwell.
and it's easy to put between the HV side and the LV side of a transformer. Colleges have been doing this trick for decades..ever hear of Carrier Current AM signals?
My parents live in rural IL (61330 area code), and are using DirectWay (DirectTV satellite internet ), with success.
No, it doesn't have the ping time you guys like, but its extremely popular among rural farmers already.
Byron
In Spain this technology are taking off. The most important power corporation here (Endesa) are doing the "Massive Test" since february in Zaragoza, (Medium/Big city with about 600,000 hab) with about 2000 test users. Before, more simple experiences taked place in Barcelona and Sevilla.
They use two technologies one with 2/3 Mb/sec (ASCOM) and another with 6/11 Mb/sec (DS2). I personaly used one of this stations and worked pretty well. The big problem at first was that "Modems" were huge (I saw it, huge an heavy), but last time a talked with one of the technicians said they can reduce it now to a DSL modem size.
Seems to work well if they take that big and expensive test.
More info at PLC-Endesa
(Beware of the Flash!!)
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That's the time harvesters,that's the time to be care
get back all this people, so ostentatious and arrogan