While sun watchers across Europe thrilled at the chance to experience a rare solar eclipse on Friday, energy companies suffered through some nervous moments. Solar power generators in Germany were unsure about how the sudden disappearance and then reappearance of the sun in the middle of a workday would effect the grid. On some days, solar power provides 40% of Germany's electricity.

Things turned out fine, with only a brief surge in the cost of electricity. Other energy sources were able to compensate without significant complications.

But you can still see the impact of the eclipse. The data comes from the European Energy Exchange and tracks actual solar power generation from German power companies during the day. Obviously, solar generation rises steadily during the middle of the day, and then falls to zero as the sun goes down. Friday, however, did not look like most days, as this lightly annotated chart, via Bloomberg's Rob Verdonck, shows.