Visit to watch more groundbreaking talks from the TED Fellows. Of all the mundane yet astonishing marvels of human ingenuity, knowing what it takes to heat a room to a comfortable temperature is TED Fellow Kathy Hannun's favorite. She takes us on a journey across the planet and under the sea to emphasize the dangers of modern heating, and offers a safer, planet-friendly alternative that taps into the geothermal energy right below our feet. The TED Talks channel features the best talks and performances from the TED Conference, where the world's leading thinkers and doers give the talk of their lives in 18 minutes (or less). Look for talks on Technology, Entertainment and Design — plus science, business, global issues, the arts and more. You're welcome to link to or embed these videos, forward them to others and share these ideas with people you know. Become a TED Member: Follow TED on Twitter: Like TED on Facebook: Subscribe to our channel: TED's videos may be used for non-commercial purposes under a Creative Commons License, Attribution–Non Commercial–No Derivatives (or the CC BY – NC – ND 4.0 International) and in accordance with our TED Talks Usage Policy (). For more information on using TED for commercial purposes (e.g. employee learning, in a film or online course), please submit a Media Request at
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