Chemical engineer and inventor Mária Telkes worked to harness the sun's power for nearly 50 years. She designed and built the first successfully solar-heated modern residence in 1948 and identified a new chemical that could store solar energy like a battery. But she was undercut by her all-male MIT colleagues. Despite this, upon her death in 1995, she held more than 20 patents. The new episode "The Sun Queen," examines how Telkes is now recognized as a visionary pioneer in the field of sustainable energy.