As more solar power is introduced into our grids, operators are dealing with a new problem that can be visualized as the “duck curve.”
Utility companies use models to predict demand and operate as efficiently as possible by supplying more power during times of higher demand. But the introduction of solar power has brought about problems in these demand curve models.
Since solar power relies on the Sun, peak solar production occurs around midday, when electricity demand is often on the lower end. As a result, energy production is higher than it needs to be, and net demand—total demand minus wind and solar production—falls. Then, when evening approaches, net demand increases, while solar power generation falls.
This discrepancy results in a net demand curve that takes the shape of a duck, and the duck curve gets more pronounced each year, as more solar capacity is added and net demand dips lower and lower at midday.
The drop in net demand at midday basically creates two problems:
- Solar energy production wanes as the sun sets, just as demand for energy typically peaks. Utility companies are having to ramp up production to compensate for this gap, often overstressing a grid that is not yet set up for these peaks.
- Traditional sources of energy like nuclear and coal are only economic when they are running all the time. If you have to turn them off at mid-day because the power is supplied by solar, they become economically unfeasible.
Due to overproduction, solar power is already being wasted in some places where the technology is widely used, like California.
The problem is most intense during summer or spring when part of the solar panels has to be turned off to avoid overloading or even damaging the power grid.
