Summer blackouts may occur, customers in southern California are being told, as the grid operator puts power rationing measures in place. The state just decided to shut down its last nuclear power plant by 2025, while legislation is in place to build no new coal-fired plants. Replacing the Diablo Canyon nuke is deemed ambitious and ‘very expensive’ - new-build CCGTs and renewables need to fill the capacity gap rather swiftly.
California has mandated that 50%t of its electricity come from renewable fuels by 2030; according to findings from the Institute for Energy Research, the state currently sources 30% of its utility-scale electricity from renewable fuels and 59%from natural gas.
ISO calls for power rationing
In a stark warning, the California Independent System Operator (ISO) asked the electricity consumers in Southern California to conserve electricity especially during the late afternoon when air conditioners typically are at peak use. Several ‘Flex Alerts’ were being issued.
Eager to avoid blackouts, consumers are urged to conserve electricity to reduce the risk that power plants could run out of natural gas fuel and trigger rolling blackouts.
‘Inadequate’ gas pipeline system
Gas supplies are tight in most of California due to a gas leak that occurred last winter at the state’s largest underground gas-storage facility, Aliso Canyon. Southern California uses a system of electric transmission lines, gas pipelines and gas storage facilities that must all run smoothly to get sufficient electricity. If any part is disabled, electricity shortages can result.
Bottlenecks at major gas transmission lines further complicate matters. Pipelines to southern California reportedly only supply about 3 Bcf of natural gas a day, which is below the daily demand that can reach as high as 5.7 Bcf — almost twice the daily supply of pipeline capacity, which is why storage facilities are needed.
Analyst criticised California’s pipeline system “is not adequate to supply enough natural gas to meet daily demand that can be almost twice what can be brought in daily that emergency demand reduction measures must be mandated this summer – yet this is no longterm solution as the capacity gap widens.
How to replace Diablo Canyon?
Retirements of California’s last two nuclear units – that produce 9% of the state’s electricity– need to be carefully timed in order not to exacerbate the current power crisis. Replacing the electricity from Diablo Canyon will be ambitious and "very expensive". Emergency measures include using diesel fuel, while the contribution of renewables is hard to predict. Alarm bells are starting to ring as the state is getting much less than the intended energy from its Ivanpah Solar Electric Generating System – the world’s largest solar plant
The Institute for Energy Research (IER) remarked that “California has been designing through regulation and mandates an electricity system largely dependent on the weather. Time will tell how this experiment works out.”