The California Independent System Operator Corp. (ISO) analysis finds electricity supplies will be sufficient to meet the 2015 summer peak even under the extreme scenario of hot temperatures that only occur once every decade or so. A boost to grid reliability will come from additional generation, mostly solar, that has interconnected to the system, stable imports and only moderate peak demand growth. The ISO’s analysis – 2015 Summer Loads and Resources Assessment – was released today.
Although the multi-year drought is reducing hydroelectric availability to the lowest level in 10 years, it will not materially impact grid reliability. Also, energy imports to the ISO are expected to be normal.
The 2015 summer assessment, developed in close coordination with state energy agencies, shows adequate operating reserve margins under a normal weather operating scenario and even in an extreme scenario under weather conditions that occur about once every 10 years where operating reserve margins are estimated to be about 11 percent, which is healthy; normal to extreme hydro projections of less hydroelectricity under anticipated water runoff.
Total generation capacity available from all resources is expected to be 54,322 megawatts, while the summer peak is projected to be a slightly over 47,000 megawatts, compared to the 2014 summer peak of 44,703 on September 15. (The all-time summer peak was set on July 24, 2006 at 50,270 megawatts.)
Since summer of 2014, 2,328 megawatts of new generation has been added to the grid with solar resources accounting for 96 percent of the interconnections.
http://www.caiso.com/Documents/CaliforniaISOFindsSummer2015SupplyAdequate.pdf