Robert Bussard on Fusion Power

September 21, 2012| Fusion|3 Minutes|By AAG

Dr. Robert Bussard shares his vision for clean, affordable fusion power. The late Dr. Bussard was a founding member of America’s fusion power establishment, spent over 20 years developing the Polywell fusor, which he claimed to generate over 100,000 times the fusion power of Farnsworth’s original experiments. Polywell was awarded the “Outstanding Technology of the Year” for 2006 by the International Academy of Science, and though Bussard passed in 2007, his research team continues to develop the Polywell fusor.

Bussard was best known as the namesake for the legendary “Bussard Ramjet”. He conceptualized the device in 1960 during his tenure in the Nuclear Propulsion Division of Los Alamos National Labs, where he designed the Nerva motor – a nuclear powered rocket proposed for heavy-lift orbital applications. He later rose to the position of Assistant Director of the Atomic Energy Commission under Robert Hirsch in the early 1970’s, where they founded the fusion power research program for the United States.

Bussard describes his disenchantment with big-science Tokamak research that led him to return to the roots of fusion power with the “Polywell” project that he initiated in 1986. Funded for over 20 years by the Department of the Navy, Bussard’s EMC2 corporation was tasked with solving 19 fundamental challenges that stood in the way of designing commercially viable Farnsworth fusors.

The Polywell design is a modified Farnsworth-Hirsch style fusor which traps electrons in a magnetic confinement inside its hollow center. The negatively charged electrons then accelerate positively charged ions for the purpose of achieving inertial electrostatic confinement fusion. Bussard theorized that by utilizing magnetic fields he could avoid losses from electrons striking the grid, and he reported achieving fusion rate of 10^9 fusion reactions per second as a result of the magnetic shielding, which is about 100,000 times greater fusion power than Farnsworth achieved.

Polywell was designed for high-efficiency fusion power and also for portability, which was required to satisfy the Navy’s needs for ocean vessels and submarines. These characteristics also make it suitable for high-output fusion power for space applications. While Bussard’s first intended application was an 8-foot diameter naval reactor capable of generating 100-megawatts of output energy, the ultimate goal for Polywell was to facilitate the development of a high-velocity transorbital spacecraft capable of reaching the moon in less than 8 hours time.