Smart meters empower customers to take control over their energy usage. These devices are one of the foundational technologies for the smart grid, and San Diego Gas & Electric (SDG&E) will be one of the first utilities in the country to equip all of its customers with a smart meter. The utility, which was once installing 7,000 smart meters per day, will complete its smart meter installation in December 2011.

SDG&E partnered with VSI Meter Services (now Grid One Solutions) to deploy 1.4 Itron smart electric meters and 850,000 gas modules to its customers. Since that time, SDG&E has been the first utility in the country to file a comprehensive Smart Grid Deployment Plan, which is available at www.sdge.com/smartgrid/deployment/index. This plan outlines a road map for the utility's future.

SDG&E linemen are taking the smart grid a step further by installing anemometers and Intellirupters to boost the system's reliability and safety. By installing two smart grid technologies listed in the deployment plan, the utility is already noticing the benefits.

Coinciding with its smart meter deployment, SDG&E began exploring tools to detect extreme weather conditions in its service territory. The utility serves an area filled with canyons and valleys prone to Santa Ana winds that can spread fires at extreme speeds. These winds wreak havoc on the company's electrical system because they can slap heavy lines together or pick up branches and debris and carry it into power lines. Because the winds are so dry, the debris can easily catch fire and spread.Electric Tool Corp., and as a result of working on the steel poles, they have altered their grounding practices.

To solve this problem, SDG&E's supervisory control and data acquisition (SCADA) line crews have installed wireless anemometers from Campbell Scientific throughout the service territory. These devices give the utility remote weather-monitoring capabilities. Without them, the company would have to rely on the sparsely located public weather stations. SDG&E needed more detailed information near the locations of its electrical systems, so the linemen installed additional anemometers. SDG&E now has the country's fourth-largest weather system. And the system has public benefits because SDG&E shares the data with emergency responders.

When it comes to the smart grid, it gives the company the ability to forecast. The anemometers provide information such as wind speed, temperature, direction of the wind and barometric pressure. Line crews also have installed pyrometers, which measure the intensity of the sun as well as the cloud layer. This information is vital to SDG&E's customers, who are increasingly installing rooftop solar-power systems on their homes. In fact, San Diego has the highest number of installed residential systems of any city in California.

SCADA line crews are installing the anenometers on 15-ft fiberglass arms to keep the devices as far away from the poles as possible to prevent turbulence. The company uses ladder arm construction to maintain climbing space for the linemen when they install the anemometers. The devices, which are 18 inches long and 12 inches high, are mounted on existing power poles close to the circuits SDG&E needs to monitor.

The linemen also install photovoltaic panels from BP Solar on the power poles. The anemometers are all self-powered units that include solar cells and a battery backup. The devices are in cellular communication with SDG&E's SCADA system.

The exponential growth of anemometers has allowed SDG&E to collect more data from the field. Some of the anemometers are located in valleys or areas with higher wind speeds. Since these devices are sometimes far apart, the utility can get a good picture as to where the strong winds are coming from as well as higher risk locations.

When deploying the anemometers, SDG&E worked closely with the Western Weather Group. The company provided the field workforce with training on how to check that the sensors are calibrated to factory specifications as well as how to conduct yearly maintenance. In addition, the company offered in-house training at its skill training facility. At this facility, future linemen, apprentices and troubleshooters can refresh their knowledge or get hands-on training.

The second smart grid technology SDG&E has installed is the Intellirupter Pulse Closer, manufactured by S&C Electric. This automated high-voltage switch provides fault interruption and automatic wireless control on overhead distribution electrical systems. Linemen install the controller for the device on SDG&E's system with SCADA options for remote and automatic control, and restoration of the distribution system.

The Intellirupters weigh about 900 lb and measure 8 ft by 36 inches by 12 inches. Linemen rely on boom trucks to hang these big metal boxes horizontally. A four- to five-person crew has two lifting eyes on the Intellirupter so that when they move it, it is balanced to hang straight for the linemen. A lineman then works up on the structure to bolt the device to the pole. It typically takes a line crew a day to two to install a pole and an Intellirupter. After the installation is complete, the company's electricians and SCADA technicians check to make sure the device is built for its company's standards and spend about four hours testing the relays. The crew will then switch in the service and release it.

When the linemen began installing the Intellirupters, SDG&E's standards engineering department traveled to all of the utility's operating line districts, discussed how the standards changed, and explained how the Intellirupters should be installed and how they differed from traditional reclosers. This road show helped to train the linemen and field workforce about how to operate and maintain the equipment. In addition, some of SDG&E's technicians visited S&C's headquarters in Chicago to obtain training from the factory on the reclosers.

During these training sessions, SDG&E engineers allowed linemen to work on a portable device to learn how the technology works. In essence, the pulse-closing technology provided in the device allows for low energy testing of overhead distribution lines. Linemen can then verify that the distribution power line is clear of faults before closing and restoring service to customers. This pulse-closing technology significantly reduces stress on the distribution system components and reduces voltage sags experienced by customers upstream of faults.

Before SDG&E had the new technology, the utility had more conventional reclosers on the system. These reclosers would send out a burst of electricity down the line, compared to the Intellirupters, which can send out a short electric pulse. When the linemen used to test a line that was open, they had to turn on the electrical pulse full force like a fire hose. Now that SDG&E has invested in the Intellirupters, however, the linemen can now test at a water faucet drip speed before having to go to full capacity.

After sending out a pulse of electricity, linemen can ensure that the line is clear. Because it's not on full voltage, they can prevent an accident. As a result, SDG&E can sometimes restore partial service within minutes. Before, linemen had to physically visit the location and reclose the circuit by pulling the handle or closing the switch. Performing a hard close could blow fuses on the system and potentially cause damage. Now the utility doesn't have to wait until a customer reports an outage. With the Intellirupter, the company knows about an outage before the clients call in, because the device alerts mission control by sending an alarm through the SCADA system.

The devices have helped SDG&E to minimize outage times, but the company has to be careful to not to use the reclosing and circuit testing in extremely hot, humid or windy weather. These conditions make the service territory ripe for fires. During adverse weather conditions, the utility turns off all the reclosing to protect the system and its customers.

As SDG&E works to install smart grid technology, the utility is also swapping out its wood poles for steel poles from Valmont Industries and its wood crossarms for ones made of fiberglass from PUPI.

One reason why the utility opted to move to steel poles is because many of the wood poles were located in a fire-prone area. By installing steel poles, the linemen were able to make their system more reliable and less susceptible to damage from catastrophic winds and fire. In addition, the wood poles and fiberglass crossarms are less prone to termite damage, wood rot and breakage. In turn, these structures will need less maintenance than their wood counterparts.

SDG&E linemen are installing all of the Intellirupters on these new steel poles. Changing from wood to steel poles has altered the way that they do their work. For example, the field crews now anchor the ladder arms to the poles using rivet nuts, and they have moved away from the through bolts that are typically used for ladder arm construction. The linemen are also using carbide hole saws from Milwaukee

In the past, when linemen were working on wood poles, they could work from the pole on an energized circuit. Now that the linemen are working on steel poles, the safety practices have changed. The line must be de-energized or they must work from a bucket truck when working on steel poles.

In addition, the linemen are installing fiberglass arms, which are more durable than wood crossarms. Shifting to fiberglass also minimizes the amount of necessary hardware. Braces are no longer required, which speeds up installation for the line crews. The fiberglass arms are a nonconductor, which improves the safety of the installation.

The linemen are installing the anemometers on the fiberglass crossarms and the Intellirupters on the steel poles. These smart grid devices can work in concert to improve reliability on SDG&E's system. For example, the anemometers can give the company an overview of how the weather is changing throughout the country and then pinpoint where problems may develop. Intellirupters have multiple profiles for operating conditions. Without sending out a field professional to reprogram the Intellirupter, SDG&E can select a different profile. If a certain part of SDG&E's service territory is experiencing high winds or low humidity, then one of their mission control operators can switch the Intellirupter to a specific profile set up by SDG&E's engineering department. The switch will then operate differently to meet the conditions.

In addition to these smart grid devices, linemen are installing bypass switches so they can perform maintenance on the devices without causing outages or putting strain on mechanical jumpers. These switches have proven to be a major improvement in terms of maintenance.

These devices have significantly improved the amount of data coming back from the system, making it more balanced. Now if the linemen are asked to hang a transformer, they know exactly which phase to tap.

The smart grid devices also help the troubleshooters who inspect large sections of line. With the data from the anemometers and the Intellirupters, they can pinpoint problems more accurately. Some of SDG&E's service territory can only be patrolled by helicopter or on foot. If the devices sense a smaller area for an outage, it reduces the necessary amount of patrolling for the troublemen, who no longer need to wait until daylight to get the job done.

Over the years, SDG&E has been able to increase its reliability. The smart grid tools have allowed the operators, planners and troubleshooters to restore power more quickly. In fact, the utility was just named the most reliable utility in the country by PA Consulting Group, and for the last five years, it has been recognized as the most reliable utility in the West.

By making its system more reliable, SDG&E is able to improve its customer service. Through the smart grid technology, the utility is also able to streamline the work for its linemen, increase the amount of data about its system and poise its grid for future applications.