In its annual forecast of summer electricity conditions, the California Independent System Operator (ISO) predicts adequate power for the summer largely because of above-normal hydroelectric supplies that will give the system more cushion than in 2018.
Energy reliability in the Southern California region, however, will continue to be impacted by uncertainty surrounding its natural gas system, primarily due to the reduced capacity and restrictions imposed on the Aliso Canyon storage facility.
The ISO's 2019 Summer Load and Resource Assessment also highlighted possible periods of steep upward demand straining the system in the late afternoons as solar production drops and demand spikes.
The assessment found a higher potential for shortages in the ability to rapidly increase output during certain times of the day, which would create operational challenges. These upward demand shortages are most prevalent in the late afternoon when solar generation output decreases while system demand is still high. The high late afternoon demand will present the greatest operational risk during late summer, as hydropower wanes and potential peak demands in neighboring states affect imports into ISO's footprint.
Overall, the report showed a 2019 peak demand of 46,511 megawatts, and cited a "low probability of a system capacity shortage" in the months of June through September. The assessment projects that 51,765 MW of available system capacity will be in place for the summer. Last summer's peak demand was 46,526 MW.
Abundant hydroelectric resources will play a major role in supplying electricity this summer, according to the report, with snowpack at 162 percent of average as of April 2, 2019, well above the 2018 snowpack of 52 percent of average. Major statewide reservoir storage levels were at 109 percent of normal.
The report doesn't specifically address transmission outages due to wildfire risk, but uses historical data on outages caused by fires.
The positive forecast for electric conditions may result in a reduced need for Flex Alerts, the program that calls on consumers to voluntarily reduce energy consumption in times
of stress on the grid. Last year's assessment predicted a 50-percent chance of a Flex Alert being called, and in 2019, the chance is forecast at 25 percent. A Flex Alert was issued for two consecutive days in 2018 and provided much needed reduction in consumption during those days.
View the entire assessment here.
The California ISO provides open and non-discriminatory access to one of the largest power grids in the world. The vast network of
high-voltage transmission power lines is supported by a competitive energy market and comprehensive grid planning. Partnering with about a hundred clients, the nonprofit public benefit corporation is dedicated to the continual development and reliable operation of a modern grid that operates for the benefit of consumers. Recognizing the importance of the global climate challenge, the ISO is at the forefront of integrating renewable power and advanced technologies that will help meet a sustainable energy future efficiently and cleanly.
Contact:
Vonette Fontaine | vfontaine@caiso.com
Anne Gonzales | agonzales@caiso.com
