Worden also mentioned some nearer-term ideas that NASA is exploring. One new propulsion concept is electric propulsion.
NASA is also funding a new program to develop microwave thermal propulsion for getting to orbit. “The idea is if you can beam power to the spaceship, so you don’t have to carry all the fuel; and then you use that energy from a laser or microwave power to heat a propellant; it gets you a pretty big factor of improvement. I think that’s one way of getting off the world.”
The principal investigator of this program is Dr. Kevin L.G. Parkin, who invented the technology and described it in his PhD thesis. He is assisted by Creon Levit and David Murakami. Caltech grad student Dmitriy Tseliakhovich has also formed a company called Escape Dynamics LLC to commercialize the microwave thermal propulsion project. (Tseliakhovich’s team project at Singularity University this past summer grew out of Parkin’s work.)
“The microwave thermal thruster using beamed propulsion is an excellent idea,” said Dr. Narayanan M. Komerath, a professor at Georgia Tech College of Engineering and a NASA Institute of Advanced Concepts Fellow. “[Kevin Parkin] picks the 140 GHz window, which apparently offers strong advantages in absorption by the materials that he uses in the propulsion system.
NASA Ames is exploring another radical new concept: a heavy-lift airship that could carry hundreds of tons. “I think that could revolutionize air transport, because it becomes very cheap and still goes 100 knots. The idea is that you could easily go to Hawaii overnight, for example… with a lot less fuel.
“The long-term answer [to the rapidly accelerating growth of travel in the developing world and the increase in greenhouse gas] is a “Tesla in the air” — using high-density batteries powered off ground-based solar grids, so your airliner stays plugged in overnight, and it’s got an electrical engine rather than a chemical engine. I think within ten years we’ll have small-scale business-level ones, and within 20, they’ll be the airliners.