You buy one adapter that converts your incoming Internet signal to a form that will travel through your home electric system. These adapters are about the size of a thick cell phone, and good ones are available for well under $100 (and prices are beginning to fall as the devices become more popular). I have both the Netgear XE102 and the Linksys PlusB10; a full list of suppliers is available on the Web site of the industry’s standard-setting organization, the HomePlug Powerline Alliance. You connect the adapter to your router or modem by Ethernet cable, and you plug the adapter into any outlet on the wall.
From that point on, your home wiring is also an Internet carrier. You can plug in a second, similar adapter anyplace else in the house and have an instant Ethernet port (yes, that means spending another $50 to $100). Or you can plug a different model, like the Netgear WGX102 (similar size and price), into any socket and create a new WiFi zone. (The adapters now available can create either an Ethernet port or a WiFi hotspot, but not both.) You can move one of these adapters from room to room or leave several of them permanently in place. On early models, the transmission speed through the electric wires was noticeably slower than through a direct connection; BPL technology is improving so fast that now there is little speed penalty. These in-home systems have escaped opposition from the ham-radio operators, both because they radiate less interference than transmission on outdoor lines and because they are “notched” to protect the hams.
That’s the benefit to the individual. The potential benefit to the country comes from another emerging BPL feature: “smart grid” operations.
The nation’s electric system is indispensable to modern life but in many ways old-fashioned. As anyone who has lived through a long post-storm power outage knows, it can take electric companies hours or days to figure out exactly where the problem is and how many customers have been affected. “It’s a one-way broadcast of energy,” says Bill Berkman, the chairman of a BPL company called Current Communications. “The companies have no knowledge whatsoever about whether the power is getting to consumers, whether enough is getting there, how the load is balanced across the system.” His company’s business includes installing small sensors on transformers and utility poles, which send status reports back to the head office over the power lines using BPL data-carrying technology. “You can monitor the voltage, the tilt of the pole, the oil pressure in the transformer drum—these all sound boring, but for a utility they are huge,” Berkman says. The company has installed smart grid systems for utilities in California, Ohio, Texas, and elsewhere. The industry trade press is full of reports about potential huge savings to utilities through automated meter reading, easier maintenance, and other advantages of smart grids.
The real value of a self-sensing electrical system, according to Berkman and others, lies in the electrical generating plants it may keep from being built. This benefit comes from the possibility of using a smart grid’s monitoring capacity to detect exactly when, where, and why power use is surging—and to shift or limit it in precise ways, to avoid costly spikes in demand. The bane of the power business is the “peak load” phenomenon—providing the extra 5 percent to 10 percent of power to run air conditioners on a summer afternoon or electric heaters in the winter. Meeting that small increase in demand is disproportionately expensive, because the extra generating capacity is usually more polluting and less efficient than the normal plants. “If you can reduce the peak even a little bit, you can reduce costs a lot, especially in some regions of the country,” says Susan Tierney, a former utility regulator in Massachusetts (and my sister).
In principle, smart grid systems should be able to do just this. Devices on equipment with high power demand—air conditioners and refrigerators in the home, a wide variety of commercial equipment—could, with the customer’s agreement, automatically slow or shut these appliances down briefly as peak demand neared. Or they could report, via thermostat readouts or some other measure, real-time price changes, so the customer could decide what to turn off. Many new power plants are built to meet peak-load demand. In much of the country building new plants is difficult or impossible because of environmental or other regulatory factors; in all parts of the country, power generation creates greenhouse gases or nuclear wastes. If BPL can reduce those, it’s got my attention—as it’s already got my customer loyalty.