San Diego Gas & Electric is installing several smart grid technologies on the electric grid in the San Diego region that are creating a more resilient and responsive energy network for local residents. These technologies include wireless sensors that automatically detect outages and other problems on the electric grid, and devices that smoothly integrate environmentally beneficial renewable energy. With the installation of these technologies, SDG&E is creating a more automated electric grid that promotes greater awareness of system conditions and can quickly respond to changes and events. In many cases, this grid will even be able to use this information to “heal” itself remotely or sense problems before they occur.
“San Diego’s electric grid is becoming one of the most advanced and reliable energy systems in the nation,” said David Geier, vice president of electric operations for SDG&E. “The grid can respond immediately to outages and is increasingly resilient to events, while being more sustainable overall through the integration of clean energy. We are proud to be implementing these innovative smart grid technologies for the benefit of San Diego residents.”
By using an efficient broad-based wireless network provided by a local San Diego company called On-Ramp Wireless, the fault detectors described above immediately send alarms to grid operators if a problem occurs anywhere along the power lines. Instead of the time-consuming process of dispatching crews in the field to look for faults on electric wires during an outage, SDG&E will know where the outage occurred on the electric line and can quickly send crews to that location based on the automatic wireless signals sent by these devices. SDG&E has installed 2,000 of these devices throughout the region and intends to install 10,000 by 2017.
In addition to enhancing reliability and reducing outage times through these wireless sensors, the automation of the electric grid will also provide numerous environmental benefits by efficiently integrating clean renewable energy onto the system. These new cleaner forms of renewable energy – wind and solar – pose some challenges to utilities because they are intermittent by nature. If a cloud moves in front of the sun or the wind stops blowing, the power output of these sources can become unavailable suddenly and indefinitely. The smart grid is designed to counter the highly intermittent nature of renewable energy sources through new technology that senses and accounts for any variability in near real time.
For example, SDG&E is deploying a new voltage stabilizer called a “dynamic VAr device” on a circuit with a large solar array that is already causing voltage fluctuations on the grid. The new device will level out the voltage drops caused by the fluctuating solar generation, thus preventing potential power quality problems. SDG&E also installed five batteries in 2012 – three small units in the community and two large units at SDG&E substations – designed to provide power and support the grid when the output from renewable sources fluctuates or becomes temporarily unavailable.
SDG&E also has embarked on a condition-based maintenance program that can extend the life of valuable infrastructure by remotely “sensing” potential problems and alerting utility crews when maintenance is needed. SDG&E has installed these sensors on 75 percent of substation transformers and has used them to detect several problems before damage occurred to these million-dollar pieces of equipment. This not only saves money and reduces maintenance trips in the field, it can prompt repairs to vital infrastructure before they fail, which enhances electric grid reliability and safety.
SDG&E in late 2012 launched a new Outage Management System that leverages the utility’s 1.4 million smart meters and other smart grid technology to speed up the detection of power outages and help restore electricity to customers faster than ever before. By combining the capabilities of this system and the advances described above and continuing to install new smart grid technologies, SDG&E will create a safer, more efficient and greener energy system for San Diego residents.
All these efforts are aimed at transforming older infrastructure into a new, more versatile, “self-aware” energy grid that is able to sense and respond to real-time information faster to enhance reliability and make the system more sustainable overall. The “self-healing” aspect of the grid is a key element of SDG&E’s overall smart grid deployment effort, which is one of the most ambitious in the nation and consists of more than 60 separate initiatives for the benefit of the region.