Southern California Edison designed and installed what it calls the country's most advanced neighborhood circuit with aims of making the grid more reliable.

          "A high-tech world can no longer afford a low-tech electricity grid," said CEO John Bryson.  "With smart grid technology, power outages will be fewer and shorter."

          SCE's grid is split up into 4,200 circuits that carry power from neighborhood substations to homes.

          The advanced version serves one neighborhood now -- but SCE is in the midst of a $14 billion upgrade and plans to roll out the technology in more areas, it reported.

          The big change is a digital controller that identifies, analyzes and isolates power problems.

          Older circuit designs rely on electro-magnetic devices that shut down the whole neighborhood's power or at best half in an emergency event while the digital version can isolate one fifth of the circuit, said SCE.

          The circuit is linked to grid operators with fiber optic cable that can alert them to a problem at one customer's place.  The old system could only indicate the status of the whole circuit.

          SCE's system is the first in the US to use powerful new surge protection devices called fault current limiters, said the IOU.

          The limiters can detect and control fluctuations in current levels caused by short circuits almost instantly, protecting infrastructure from damage.

          The circuit's computers can monitor the temperature of underground high-voltage lines that supply them.

          Older systems couldn't -- and supply lines had to be run below capacity because temperature data was not available.  The new system allows maximum capacity on the lines.

          SCE will be able to plug in a portable substation to the new circuit that will supply the neighborhood with power in times of an overload, thus preventing outages, said the firm.