Source: Solar eclipse on August 21 will affect photovoltaic generators across the country – Today in Energy – U.S. Energy Information Administration (EIA)

As many of you know, a total solar eclipse will take place across the United States on Monday, August 21. Unfortunately I will not be there to enjoy this magnificent natural event, even if it must be said that the Bay Area is not within the path of totality (the sun coverage will be about 75%).

Now, I know that this is highly unlikely to be the first thing that people think of when talking about a solar eclipse, but one of the issues that it will carry with it will be the huge loss in solar PV production that will occur during the phenomenon. The integration of Variable Renewable Energies (VRE) in the electricity grid is one of the main topics of my MERCURY project, so I’m really interested in this aspect.

This situation will be particularly tricky in California, because – although it will not be interested by total eclipse – it is the state with the highest PV capacity installed in the US. The eclipse will cause up to a 4 GW production loss (or even 6 GW according to other sources). The problem is not the loss per se (never heard about night?? 🙂 ), but the speed of this loss, that has been quantified in 70 MW/minute. As electricity supply and demand must be balanced at all times, the operators will have to make a great effort to ensure grid stability. To this purpose, they will count on flexible technologies, such as gas and hydro plants (fortunately this has been an extraordinarily rainy year in California!).

Are they gonna make it? We’ll see!

Here are a couple of other interesting articles on this topic, more tailored to the general public, from Vox and Wired.