A crowd gathered at Montrose Beach on Sunday morning for a Solar Fest, advocating clean energy.

The festival was part of Sun Day — two words — the first-ever nationwide day calling for the large-scale deployment of solar power and other clean energy sources. More than 450 Sun Day events were held nationwide on Sunday.

Organizers of the Solar Fest said solar power is now the cheapest form of energy in the world, clean energy jobs are rapidly growing, and communities around the U.S. are benefiting from both cleaner air and lower energy costs

In Illinois, organizers said, there has been a 19-fold increase in the amount of electricity generated from solar energy compared with five years ago.

The Solar Fest on Sunday featured sun-powered demonstrations, a mini-solar house, solar installers, an EV car show, live music, and other attractions.

The goal of the Solar Fest was to "help people learn how to take actionable steps toward supporting clean, sun-powered energy in their homes and their communities," organizers said.