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11/03/2011 Why's power hard-wired? Dollars and physics

NEW YORK (AP) — With our wireless Internet connections and far-ranging cell phones, it's easy to forget the hard-wired electricity that powers our homes and gadgets — until the lights go out.

But the freak fall snowstorm that left millions of homes in the Northeast dark this week is delivering a startling reminder of the limits — imposed by both dollars and physics — that keep many Americans reliant on above-ground wires for power, more than a century after Thomas Edison created the modern electrical utility business.

Despite a technological revolution that has transformed the ways people communicate in barely a generation, the mechanics of delivering the electricity that powers all those new devices remains fundamentally unchanged.

The outages have ignited anger among some utility customers, many of whom also lost power during Hurricane Irene in August. Some are demanding to know why power providers haven't spent the money or adapted the technology necessary to prevent such problems.

The short answer is that moving electrical wires below ground, where they'd be protected from falling trees, is so expensive that it would likely send consumers' electric bills sharply higher.

And then there's the fact that a new and improved technology for moving power — one that would replace wires — doesn't yet exist.

"If Alexander Graham Bell came back today he wouldn't necessarily recognize the telecommunications system," said Bill Zarakas, of The Brattle Group, a Cambridge, Mass.-based economic consulting firm specializing in the electric power and utility industries. "But if Thomas Edison came back today he would completely understand our entire grid. It hasn't changed very much from a design standpoint."

A big part of that is physics. The signals transmitted to our wireless devices are photons that move readily through air. But the electrons that make up the power supply move much more efficiently through dense substances like metal wires. So far, nobody has figured out a way around that.

"I don't really think the capital is the constraint. I really think it is, to a great degree, the technology and what makes sense from a price point to consumers," said Ralph LaRossa, president and chief operating officer of Public Service Electric & Gas Co. "There is some kid in a garage who's going to come up with something great. It just hasn't come out yet."

LaRossa's company can't afford to wait. Last weekend's storm cut power to 571,000 of its 2.2 million New Jersey customers. By Wednesday afternoon, 37,000 remained without power, but even many of those with the lights back on were frustrated. LaRossa says he gets it, but that he doesn't believe most people grasp the costs that would come with moving lines underground.

Zarakas said many electrical providers, struck repeatedly by severe storms, are studying the costs of "hardening" power supply systems by moving lines and transformers below ground. But installing lines below ground can cost 8 to 10 times what it does to hang lines from poles, experts say.

A 2009 report by the Edison Electric Institute estimated above-ground installation costs at between $150,000 per mile in rural areas to $5 million per mile in cities. Installing lines underground ranges from $1,100,000 per mile to $23 million per mile in urban areas.

Zarakas points out that utilities request rate hikes based on their total investment in infrastructure. Customers are already paying rates based on the cost of installing existing above-ground lines. If the lines are relocated, utilities would seek rate increases covering not just the differential, but the cumulative costs.

"The cost to underground all our facilities would be astronomical," said LaRossa of PSE&G. "We don't believe that it will ever come close to being an economic advantage for folks to go ahead and underground all the facilities."

Many cities, as well as suburban neighborhoods built in the last 25 years, depend on underground lines. But the density of cities helps spread the costs, and newer developments, often mandated to put power lines underground, are built without having to replace an existing above-ground system.

In an age of technological marvels, utilities and consumers are left with decidedly low-tech, real-world choices. Many utilities spend half their maintenance budget on tree trimming, money that would be saved by moving lines below ground, said Ken Buckstaff of Los Angeles-based First Quartile Consulting, which compiles an annual survey of power providers. But when lines are underground it makes it much harder to locate and fix outages, he said.

Buckstaff notes that, in his own California neighborhood, residents voted down a proposal to move their power lines below ground after estimates showing it would cost the average homeowner $50,000.

PSE&G's LaRossa says customers and local officials complain when utilities prune trees too aggressively. Maybe one solution would be to replant with species of trees that grow more slowly, he said. But for the moment, he's got more immediate concerns. As of late Wednesday, he was still coordinating a list of 4,000 repair jobs needed to restore power completely. The biggest of those would bring power back to 700 customers. But 3,000 of those jobs would only succeed in returning the electricity to a single home or business. Maybe someday, technology will change that hard-wired reality.

"Right now," LaRossa said, "we've got hand-to-hand combat."

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