Following a record-breaking five-day heat wave combined with a microburst of thunderstorms bringing high winds, San Diego Gas & Electric (SDG&E) is thanking customers and community partners for their efforts to save energy and for their patience during power outages. Due to the extreme weather conditions, SDG&E reached new all-time back-to-back peak demand records of 4,781 megawatts (MW) on Sept. 15 and 4,890 MW on Sept. 16. The conservation efforts by customers limited strain on the electric grid and ensured SDG&E was able to provide reliable energy throughout the event.
"The last several days brought severe weather conditions to SDG&E's service area and we are grateful to our customers, community partners and our first responders who helped keep San Diego safe and displayed remarkable patience and responsiveness to our requests for help to conserve energy," said Steven D. Davis, SDG&E's president and COO. "SDG&E is focused on keeping our system running safely and reliably, and the support of the community was immensely helpful in enabling us to meet those goals."
On Monday, Sept. 15, preliminary results show that a total reduction of approximately 70 MW was achieved through demand response programs that were activated. Residential customers saved energy and earned bill credits through Reduce Your Use Rewards, Reduce Your Use Thermostat and Summer Saver, saving approximately 30 MW.
SDG&E's business customers played a major role in achieving significant demand reduction, resulting in savings of approximately 40 MW on Sept. 15. For example, locally headquartered industrial gas turbine manufacturer Solar Turbines participates in SDG&E's Capacity Bidding Program, a voluntary demand response program that offers commercial and industrial customers the opportunity to earn incentive payments in exchange for reducing energy consumption when requested by the utility.
During the heat wave, Solar Turbines was able to reduce their energy use by approximately 6 MW. They are able to make these load reductions by a number of methods including the delay of manufacturing process start times during peak grid load periods.
Preparation key to limiting outages and safely restoring service in extreme weather
In addition to the heat, the region was hit with sudden microbursts bringing high winds and heavy rainfall in very short periods of time. These powerful storms brought severe wind, flooding and downed trees that resulted in localized outages on Sept. 16.
SDG&E's readiness helped ensure the system provided safe and reliable power to customers during the heat wave, and restoration of outages was conducted quickly and safely following damage from thunderstorms. These preparations included an increased level of crews and standby personnel in the field ready to respond to issues as they happened. Utility field crews were able to quickly begin the process of restoring power in the affected areas immediately, thanks to advanced meteorology tools that alerted SDG&E to the direction of the fast-moving storms.
SDG&E also worked closely with the California Independent System Operator Corporation to monitor the high demand and ensure the transmission system was running smoothly. In addition to all available local generation resources – both large power plants and smaller peaking units that use natural gas – SDG&E relied heavily on the Sunrise Powerlink to import 450 MW of new solar and wind capacity that was generated in the Imperial Valley region to meet the higher demands of the system at the time of the peak. Planning for the future, SDG&E has an active solicitation in the marketplace for up to 800 MW of additional resources, including a minimum of 200 MW of preferred resources, to be able to accommodate the loss of more than 1,150 MW of local generation set to retire in the next two to three years.
Safety is especially crucial during storms and extreme weather. SDG&E reminds customers to always assume that power lines are energized and make sure not to touch any downed lines, and to call for help – such as a qualified SDG&E employee or a firefighter – if someone has come in contact with energized power lines or equipment. If dependent on electrically operated medical equipment, make sure you have made backup power arrangements in case of an outage.