Powerline communication to survive but in niches

Powerline communication to survive but in niches

Summary: Powerline communication (PLC) technology has lost some of its appeal due to the gain in popularity of wireless and mobile broadband, but interest in the area will be sustained by its application in niches such as smart grids.


Getting Web connectivity and data at home via electricity lines, or powerline communication (PLC) technology, took a backseat despite the initial hype several years ago, as wireless and mobile broadband became more affordable and pervasive. However, analysts say PLC will carry on in niche uses, such as the smart grid.

PLC technology, also called broadband over powerline (BPL), was talked about more than 10 years ago, said Ian Keene, vice president at Gartner Research. He noted that there was a lot of hype back then around the idea of using the power supply lines that existed in homes or offices to become new broadband communication infrastructure.

However, the hype never made it to reality: Products were delayed into the market due to technical issues, prices were high, and field performance often did not match up to laboratory performance, he explained.

Simultaneously, while all this was going on, the bandwidth available from telco networks continued to increase, so being able to supply a few megabits per second (Mbps) of Web bandwidth was just not competitive from the carriers' standpoint, Keene added.

Julie Kunstler, principal analyst for telecommunications at Ovum, said PLC was not infallible in terms of connection quality in the first place. "You could get connected [to the Web], but the connection wouldn't always be good or stable.

"Powerlines were never made to handle communications. Think about it, you're asking the electric network to handle communications [besides] electricity," she pointed out.

The result was a poor and inconsistent communication network, since PLC would unsurprisingly suffer from interference problems with other appliances that are also plugged into the electricity at home, she argued. "What happens if I can't turn on my microwave oven or refrigerator because of an interference problem?"

Consumers obviously want a home broadband network that always works without having to think about it, she added. "PLC often could not meet that requirement and so did not become the technology of choice."

The other reason why PLC did not take off was because alternatives proved more appealing, Kunstler noted. Wireless technology became very successful and inexpensive both in and outside the home, and in some markets, third- and fourth-generation (3G and 4G) mobile broadband has since surpassed desktop Web access.

Bill Rojas, director of telecom research at IDC Asia-Pacific, noted that the emergence of HSPA (high speed packet access) mobile broadband technology and now long-term evolution (LTE) offer more attractive cost-performance for home broadband access, especially in developing markets. And this basically meant PLC would only be utilized where even mobile broadband cannot be delivered cost-effectively or fast enough, such as particularly remote rural areas, he said.

Kunstler disagreed when asked if PLC would more likely take off in developed countries, which typically have more established electricity infrastructure. She explained the reason was simply because if the electrical cables were very old, the BPL connection would not be good enough.

Not at death's door
Despite these issues, industry watchers were unanimous that PLC would not fade away as it still had its uses, just not in home broadband.

The promise of Internet delivery via BPL may not have materialized, but PLC has found a niche in the smart grid space, said Varun Nagaraj, senior vice president of product management and marketing at Echelon, which designs energy-control networks.

According to him, narrowband PLC is the leading technology used around the world for smart metering, with millions of PLC-based smart meters deployed every year.

Ovum analyst Kunstler highlighted that utility companies themselves are "very big users" of PLC technology in their own networks. It makes sense for them, since the total cost of ownership is low as they already own the electricity grid. "They don't have to pay to use their powerlines for data communication throughout that network. PLC hence works very well for automated remote communication with smart meters."

PLC will ultimately find a niche purpose in vertical markets, she said, adding: "I don't think it will ever be dead. But it would never get as big as proponents hoped."

Topics: Broadband, Networking, Telcos, Tech Industry

Jamie Yap

About Jamie Yap

Jamie writes about technology, business and the most obvious intersection of the two that is software. Other variegated topics include--in one form or other--cloud, Web 2.0, apps, data, analytics, mobile, services, and the three Es: enterprises, executives and entrepreneurs. In a previous life, she was a writer covering a different but equally serious business called show business.

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  • Powerline Networking is very reliable

    "What happens if I can't turn on my microwave oven or refrigerator because of an interference problem?" quote from Julie Kunstler.
    I wonder has she even tried this technology? I have been using it since 2006 and it works perfectly. I am still using the same powering network adapters that I bought back in 2006 and they still work great. They only time they have issues is when the router itself cannot connect to the internet.

    I don’t doubt that such powerline devices are subject to interference but they appear to have a built-in method of removing such interference (the adapters appear to have many capacitors which could be used for such filtering). Appliances such as the microwave, fridge and even the powerful electric shower do not interfere with the connection. The connection has always been convenient and extremely reliable for me.

    I also use a wireless router in my house. The power line adapters bring the broadband connection to a number of desktop PCs that would otherwise not receive a reliable wiresless connection. For me, mobile broadband while very fast and reliable would be very expensive as I use the internet a lot.

    I do not wish to promote one brand over another but my adapters are from Devolo. Netgear, ZyXel and Linksys also make fast and reliable adapters.

    Thank you.
    • Powerline differences for intranet access vs. internet access.

      JimboC421, you have experienced the confusion between the BPL and the home powerline networks. The article is referring to the internet connection between your home and the world wide web. BPL was to go over the big very high voltage main electrical grid that is connected to the electrical power plants of an area. It does not work well for broadband. Too much signal attenuation over the long distances and too much interference.

      What you are using is home intranet powerline networking. Because the distances are shorter within a typical residence, the voltage is lower, and the amperage is lower the home powerline solution can work very well, as you have experienced. If the residence has good quality wiring, the results are quite impressive. I have read that by 2020 the devices may be capable of delivering up to 1000 Mbps intranet capability using the house wiring. One issue that might hurt the technology are the fuse or circuit breaker box, assuming the wiring and electrical power outlets are of good quality. The signal may get stopped at the box. The other issue is having the home powerline devices on the same circuit as big electrical motors, like clothes washers, clothes dryers, dishwashers, refrigerators, air conditioners, or some stoves. My friends who use the powerline devices say the networking devices will stop working sometimes when those devices are running.
      David Hoffman
  • BPL

    BPL that provides narrowband smartgrid may be good enough today, but I think in the future, after 2020, the electrical power companies will be running more fiber optic networks to allow for more bandwidth intensive applications that provide control and information to both the electrical power company and their customers. For those of us who live in areas where most of the electrical grid is above ground, the grid could have an enormous number of WiFi, cellular, or white space small coverage area access points for voice or data connections. Lots of cellular dead spots could be addressed with mini cellular sites located on electrical power poles.
    David Hoffman
  • In-home broadband over power lines and smart-grid applications

    The article is missing the target in a few areas.

    First, keep in mind that "power line communications" covers more than a singe technology. The concept includes broadband over power lines (BPL), but also covers lower-data rate signalling, which can also be done on ac electrical wiring. Each combination of data rate and the type of ac wiring being used (building wiring vs overhead distribution lines) has its own set of strengths and weaknesses.

    When it comes to using overhead electrical wiring to conduct broadband signals for Internet access, history leaves little doubt -- the technology never lived up to its hype. The article was spot on for one of the reasons why -- electrical wiring was never designed to reliably carry high-speed data. The problems encountered included leakage from the wiring causing interference to radio services such as Amateur Radio, international shortwave broadcast and others. The reliability of the Internet access BPL systems deployed by utilities was also rather poor. In working to resolve interference issues with access BPL, I have had the opportunity to talk with most of the electric utilities and/or BPL system operators. Most have reported that these systems just were not reliable. Between the interference problems, the poor reliability and the costs, all but a tiny handful of the access BPL systems tried in the US have been shut down by the utilities, sometimes at a cost of many millions of dollars.

    This is a point important to my comments on this article because if sending high-speed Internet access bits over electrical-distribution wiring was unreliable, it will be no more reliable to send the same type of bits using the same equipment over the same wiring for smart-grid applications. To date, the vast majority of the developing smart-grid industry is using something other than BPL as the backbone for smart-grid applications. Technically, this is exactly the right choice, because using the grid to try to control the grid is a pretty poor idea, as control is needed most when the grid has developed some sort of problem. Wireless or fiber applications seem to be the technologies of choice.

    The article also missed the mark significantly with respect to in-home BPL. First, there are many tens of millions of in-home BPL modems deployed right now. While this is only a subset of the technology used within buildings, the deployment of in-premise BPL is far greater than the article implied. Premise wiring is being used to send broadband signals around a home, as well as lower-data rate signaling used for some control purposes.

    The developing smart-grid technology is primarily focused for now on utility control of equipment, but a major piece to this puzzle is going to be what is known as "demand-side management," where utilities can be given control of some appliances within a home, or a consumer can run computer applications that accomplish some control. The benefits of this type of technology are just now being explored, but I think that management of loads will become more and more important over time. Right now, many power grids are operating above capacity. Utilities sometimes have to manage this by the use of things like rolling blackouts. How many people would choose to have some process turn off their air conditioner for 15 minutes, as opposed to having a rolling blackout remove power for a few hours time? The utility can also use the technology to implement price structures tied to the spot price of the electricity they have buy at peak times. This is a two-edged sword, allowing a utility to better control costs, while allowing consumers to buy some of their electricity at the lowest possible rate. Control of appliances and other loads inside of premises is an important part of the overall potential of the smart grid.

    Although it is a poor idea to use the distribution lines as a backbone, there is no more natural approach to control appliances within buildings than to do so using the wires they are already connected to. What doesn't work for distibution lines can and does work within buildings. The in-building AC wiring does still have some issues, but not as extreme as trying to use overhead distribution wiring, and any broadband technology has pros and cons, so in-premise BPL is just like WiFi and other technologies in that regard.

    For in-premise applications, industry groups such as HomePlug and the HomeGrid Forum have devised protocols that have resolved most of the interference issues involving radio services. International regulations have been put forward that do the same. (In the US, the FCC is still way behind this power curve, but it may yet be persuaded to join the rest of the world with good regulations to address interference.)

    So, IMHO, the article was incorrect in its conclusions about in-premise BPL. It did touch on interference issues, but didn't outline how and why it can be resolved and it didn't touch at all on the present inadequate status of some regulations and standards with respect to BPL interference.

    Ed Hare
    ARRL Laboratory Manager (the National Association for Amateur Radio
    225 Main St
    Newington, CT 06111
    Tel: 860-594-0318
    Email: W1RFI@arrl.org
    Web: http://www.arrl.org/bpl