Having been influenced by science fiction early in his life, he pursued a career in engineering to ultimately study space colonization powered by photovoltaics and solar thermal concentrators. While working at Lockheed Martin's Skunkworks on the X-33 project as an intern, and researching a space solar power project at Georgia Tech, he learned about the physical and economic constraints that would be placed on such an endeavor.
He accepted a position at NASA's Marshall Space Flight Center in Huntsville, Alabama, where he discovered the book Fluid Fuel Reactors in a coworker's office. The book described at considerable depth the thorium fuel cycle and molten salt reactor, and Sorensen became interested in these technologies both as an energy source for space colonization and as a safer and more efficient alternative to conventional nuclear power on Earth. He started a blog and forum, Energy From Thorium, and arranged to have Oak Ridge National Laboratory Molten-Salt Reactor Experiment documents digitized.
Sorensen is currently pursuing a master's degree in nuclear engineering at the University of Tennessee, and is co-founder of Flibe Energy.
- Youtube PROTOSPACE presentation where Kirk shares his own history along with the history of thorium research in the mid-20th century.