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Internet World Stats > Site Links > Internet
Broadband
BPL - Broadband Over
Power Lines
By Enrique De Argaez,
webmaster
Broadband via electrical wires is
certainly an encouraging idea since nearly every home in the
world is served by power lines. What's more, most residences are
threaded with electrical wires terminating in multiple outlets in
almost every room. So homeowners can get a high-speed Net
connection -- up to 3 megabits per second -- just by plugging a
special modem into any outlet. That matches cable modem speeds
and outpaces most DSL offerings.
What is BPL?
Broadband over Power Lines (BPL) also goes by a few other
names and acronyms: Power Line Communications (PLC, Power Line
Telecommunications (PLT), and Power Line Broadband (PLB) are
terms also used. Most of these papers and links use the term
"BPL." There are a number of types of PLC systems, using
different approaches and architecture. All are "carrier-current"
systems, a term used to describe systems that intentionally
conduct signals over electrical wiring or power lines.
The principle behind BPL is simple: Because electricity courses
over just the low-frequency portions of power lines, there's room
for data to stream over higher frequencies. For years, utilities
have sent basic network-maintenance data across their lines at
relatively low data rates. Now, by installing more sophisticated
computer chips into the network, they can send and receive fast
data streams for more high-bandwidth applications, such as
real-time, always-on meter reading. (Say good-bye to the friendly
meter reader.) And for the first time they can offer new customer
services, such as voice-over-Internet or even video on
demand.
That, however, will require significant upgrades of utility
substations and power lines. And nobody knows exactly how big an
investment will be necessary. First, power companies have to
mount boxes on certain utility poles to deliver data signals.
Early estimates of installation costs range from $50 to $150 per
home passed, plus $30 to $200 more for modems in each home,
according to a study by EPRI and its consulting arm, Primen.
Internet service provider EarthLink Inc. (ELNK ), which is
testing BPL schemes with Con Edison, says that to make money from
selling broadband access at $20 to $30 a month, a utility may
have to get installation costs down to $20 per home passed and
less than $100 per modem.
Given the challenges, utilities will welcome any cost savings
from improved energy management. By injecting intelligence into
the farthest reaches of the power system, utilities can monitor
their networks in ways never before possible. Currently, for
example, power companies don't know about local outages until
customers report them. With BPL systems watching the flow of data
to individual homes, they can pinpoint the neighborhoods without
light. While testing residential broadband service in Briarcliff
Manor, N.Y. this summer, Con Edison discovered that BPL could
help detect impending faults. A residential customer noticed that
his Web service was slowing down. Con Edison crews traced the
problem to a cracked insulator on a pole next to his house. Now
the company is modeling normal circuit conditions, then looking
at even slight deviations to spot budding problems on its
systems. That's a far cry from periodic street maintenance
checks, which Con Edison and others mainly rely on today.
In an era of increasing power usage by computers and other
digital devices, many utilities are hoping BPL will bring them
closer to an elusive goal: demand management. To encourage
conservation, power companies would like to charge customers more
during peak demand and less at other times. To bill accordingly,
they need to measure how much power a home consumes every minute
of the day. BPL could help by taking constant measurements. Some
experts argue that existing approaches, using two-way pagers, are
good enough and that new wireless options are cheaper. But BPL
proponents say their wires are faster and more reliable.
Today the very idea of a smart electrical network is in its
infancy. But demand for cheap Web access is mounting and so is
the need for better power management. To satisfy both ends,
utilities could embrace broadband and bring the electrical system
into the Internet Age.
Web Access from Wall Outlets
One day soon, getting a broadband connection at home could be as
easy as plugging a cord into an electrical outlet in the wall.
The same power lines that deliver electricity to light rooms and
run refrigerators will transport messages, music, and video
across cyberspace. To link up computers, music players, and TV
set top boxes in a home network, people will no longer have to
mess with a tangle of wires or Wi-Fi settings. Over the
powerlines, they'll have the convenience of plug-and-play.
Many power companies on the US and the world over are exploring
so-called broadband over powerline (BPL). BPL deployment would
bring more competition to telephone and cable companies that sell
web access, more Internet penetration to rural areas and
hopefully lower broadband rates for the Broadband Internet users
worldwide.
There is Concern: RF Interference
Because power lines are not designed to prevent radiation of RF
energy, BPL represents a significant potential interference
source for all radio services using this frequency range,
including the Amateur Radio Service. Overhead electrical power
lines and residential wiring act as antennas that unintentionally
radiate the broadband signals as radio signals throughout entire
neighborhoods and along roadsides. Interference has been observed
nearly one mile from the nearest BPL source.
Others lean on worldwide trial failures as strong evidence that
the technology is doomed-for-obsolescence; during its run
bringing plenty of trouble (and interference) to areas
contemplating the option.
About the Author:
Enrique De Argaez is the webmaster of the "Internet World Stats" website. Since
2000 he has been collecting Internet Usage Statistics, and
publishing the data for over 233 countries and regions of the
world for free use by the academia, the global business community
and the general public. For more information on Internet World
Usage, please visit: http://www.InternetWorldStats.com
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