The devices were featured in a National Geographic documentary "MegaStructures: Deep Earth Drillers" about geothermal energy.
Jet Propulsion Laboratory | Jet Li | jet engine | jet | Waka Flocka Flame | Jet aircraft | Jet | JET Programme | Jet (band) | Harrier Jump Jet | Business jet | Jet engine | jet aircraft | Jay Jay the Jet Plane | business jet | The Flame and the Arrow | Jet Ski | jet fuel | JET | The Moth & the Flame | Jet (brand) | Jet Black | Flame Trees | Flame Robin | Flame maple | Flame | flame | Drill | drill | Benny "The Jet" Urquidez |