It’s been one year since Dr. Ernest J. Moniz was sworn in as the 13th U.S. Secretary of Energy.

Since then, he’s been busy. We’re marking the occasion with a look back at some big moments from Secretary Moniz’s first year in office — including landmark energy policy speeches, visits to some of the Energy Department’s National Labs, the launch of the Minorities in Energy initiative, and the dedication of the world’s largest concentrating solar power plant.

In between his many official trips and public appearances, Secretary Moniz still managed to have some fun while carrying out his official duties. He even broke new ground on social media, becoming the first Energy Secretary to have his or her own Twitter account. Through it all, he’s been a strong voice on climate change and a staunch advocate for President Obama’s Climate Action Plan.

Explore the interactive timeline above to check out some of Secretary Moniz’s biggest Year One moments.