Blog Post

The Case for Powerline Communications

Smart grid watchers spend a lot of time arguing about ZigBee versus Wi-Fi, or public versus private wireless networks. But what if the answers to these debates lie in the wiring? Power line carrier (PLC) technology (sending data over the same lines that carry electricity) has some nice advantages for communicating over household wiring and along the power lines that make up the grid. In fact, in my weekly update at GigaOM Pro (subscription required), I make the case that PLC may be set to capture a bigger share of the smart grid market than it has had so far.

That’s a bold assertion, given that wireless is king in all the major smart meter deployments and home energy networking plans underway in the U.S. today. But in Europe, PLC is taking a far larger role. Italy’s network of 30 million smart meters runs on PLC, based on technology from Echelon (s ELON), and France and Spain are looking to PLC as their main way to link up multi-million-smart-meter networks that extend nationwide. Then there’s China, which wants a low-cost PLC technology to connect tens of millions of its households.

Running data in electricity itself gives PLC technologies some unique ways to help manage power more effectively. Echelon says its smart meters and upcoming smart grid “edge control nodes” can provide “automated topology mapping” that can link every PLC-connected device to the transformer that’s powering it. That could make the technology useful for balancing EV charging and load control devices in homes, for example. Steve Nguyen, Echelon’s marketing director, told me last week that the company would announce some load control device partners in the near future.

On the home front, the 70-member HomePlug Alliance is trying out its new energy-specific Green PHY technology in a few smart grid pilots by utilities including Energy Australia and Germany’s Yellostrom. But HomePlug’s higher-bandwidth AV system is already in some 45 million devices, mostly delivering IPTV to households in Europe, giving it a potentially big base to expand into energy management. Michigan utility Consumers Energy is testing out HomePlug AV in smart meters from General Electric (s GE), HomePlug president Rob Ranck said.

GE is a HomePlug board member, and has smart meters, smart appliances and EV chargers in its portfolio, all of which could see an appeal in PLC connectivity. After all, with certain exceptions like thermostats — many of which in North America aren’t connected to household wiring — most of the devices utilities want to connect to are already plugged in.

Read the full post at GigaOM Pro here.

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3 Responses to “The Case for Powerline Communications”

  1. RF has two major advantages over PLC in the Home Area Network (HAN) in North America and one globally. The universal advantage is that RF goes everywhere. PLC seems to but doesn’t. It doesn’t go to thermostats or anywhere else there isn’t power (e.g. window and door sensors, lawn moisture sensors, temperature sensors, etc.) And PLC goes only where there is a ground wire, which is not present in roughly half the existing sockets in America (I found this out the hard way). The North American advantage is economics: you need a concentrator for every distribution transformer, and there are only five homes per transformer in North America. In contrast, the RF systems typically get from 100 to a couple of thousand homes per concentrator. In Europe, there are roughly 100 homes per concentrator, which is why PLC is economic there.

  2. Agree with you that for in-home communication HomePlug may be a great solution (e.g. smartmeter to thermostat or in-home display), but PLC/BPL technologies for communicating over transmission & distribution lines are more problematic. Transformers are the bane of any type of power line communications. PLC/BPL is more cost-effective in Europe where local distribution often has dozens/hundreds of residences per distribution transformer. Here in the US, with only a handful of residences per transformer, much more installed equipment is required to “work around” the transformer issue, at least if anything approaching high speed/bandwidth communications is required. The sweet spot may well be wireless for backhaul comm. and power line for in-home.