The patent filing (can be found here using the application number 14645306, http://portal.uspto.gov/pair/PublicPair) is based on a breakthrough of high-pressure plasma confinement that was described in a 2015 Physical Review X paper, a leading physics journal. Park told Nextbigfuture that 14 versions of the magnetically insulated grid device were made between 1994 and 2012. The last one in the series, the WB-8, achieved ~30 times better confinement than the previous one, WB-7. However, the neutron yields were much less than WB-7, indicating necessary plasma heating was missing in WB-8. This prompted re-examination of the magnetically insulated grid approach.
EMC2 went back to the original 1985 Bussard patent and found key missing steps. They revised the reactor design to correct the shortcuts and compromises that Bussard had to make for the WB6 prototype reactor. With the revision, the EMC2 team was able to solve the missing pieces and finally achieved magnetic confinement of energetic electrons moving at about one tenth of the speed of light (equivalent to 70 million degrees at 78 million miles/hour) in a new scaled down test device,WB-X (Arxiv - High Energy Electron Confinement in a Magnetic Cusp Configuration).
The key aspect of Polywell fusion about fuel heating was originally proposed by Philo Farnsworth and separately by a team of Los Alamos Laboratory scientists in the 1950s and the 1960s. The electron beam based heating of fusion fuels can be the most efficient and economical heating method for fusion, if energetic electron beams are efficiently confined. The EMC2 team is excited that they finally achieved this critical step. The use of electron beam based fusion fuel heating can greatly accelerate the path toward practical fusion power by making use of a very mature technology dating back to the old cathode ray tube and origins of television.
Park also confirmed that EMC2 no longer works on a Navy project, while expressing his gratitude for their past support. It appears that budget cuts and other priorities may have impacted Navy funding streams. As such, EMC2 is seeking private funding or other funding sources. He admitted that recent turmoil in the energy market and a limited interest in fusion energy by US investors has made his task more difficult. In addition, he expressed his frustration that there was disagreement between EMC2 and Navy with respect to ITAR (International Traffic in Arms Regulation control, which hindered EMC2’s ability to get their message out to potential investors. Park pointed out the irony that, while the Navy decided to move away from funding Polywell, they were still interested in controlling the technology.
EMC2 had worked with the State Department, which holds decision authority for ITAR issues to determine which part (if any) of Polywell technology needs to be protected for national security reasons. While the lengthy review had hurt EMC2’s fundraising efforts, Dr. Park shared the news that the State Department has decided that the Polywell fusion technology is not subject to ITAR. As such, Park promises more technical disclosure about Polywells fusion [These disclosures could be made first via Nextbigfuture].
EMC2 now has a design based on 30 years of Polywell R and D and 18 total test devices. Park estimates that a $30 million/ 3 year EMC2 effort could remove the remaining scientific concerns of successfully developing commercial fusion power technology. If successful in this final round of testing, a net power producing Polywell fusion reactor could then be built within a few years for an estimated $300 million, a small sum compared to other fusion approaches. Other approaches are discussed at Issues.org.
From a 2014 presentation, here are more slides that describe the work.
A presentation of what electrostatic fusion polywell fusion
SOURCES - Interviews with Dr Jaeyoung Park, presentations, papers and patent