CAISO: Renewable energy curtailment could hit 8,000 MW this spring
This winter’s heavy rains and snowfalls have revived California’s duck curve, a graphic representation of high levels of renewable generation, particularly solar power, that offsets baseload generation and then falls off sharply in the evening, requiring the quick ramp up of conventional generation sources.
A report late last year from ScottMadden found that the duck curve is growing more quickly than expected. That could mean that there could be too much of a good thing.
Excess generation can lead to grid reliability problems and can drive up costs. Because it is dispatched first in California, excess wind and solar generation can force other plants to shut down. But because they may be needed later when the sun goes down, the plants must run at minimum levels.
In addition, many renewable energy plants have contractual obligations, such as power purchase agreements, that limit curtailments or have specific provisions for allocating curtailment risks. Lawyers at Latham & Watkins LLP write that those provisions could come into play if curtailment climbs toward the 13 GW mark.