In this Sustainable Energy Seminar, Steffi Diem, Assistant Professor of Engineering Physics, will discuss a new design approach to magnetically confined fusion reactors that could reduce the cost and complexity of construction and increase their potential for commercial energy production.

Registration is required for this online seminar through WebEx Events. Click here to register for this and all other seminars as part of the Sustainable Energy Seminar series.

Abstract: 

The potential to use fusion as a carbon-free, fuel-abundant energy source to meet the world’s growing energy demands has motivated significant US and international research. One research path towards the realization of fusion energy involves tokamaks that magnetically confine hot plasmas in the shape of a torus. Almost every tokamak fusion reactor in the world relies on magnetic induction from a central solenoid to drive the current necessary to create a fusion grade plasma. Minimizing or completely eliminating the need for a central solenoid in a tokamak would greatly simplify the construction and reduce the cost of these devices, increasing their viability for commercial energy production. Solenoid-free startup techniques such as helicity injection (HI) and radiofrequency (RF) wave injection offer the potential of reducing the technical requirements of, or possibly the need for, a central solenoid. A major upgrade is underway for the spherical tokamak facility, Pegasus-III at the University of Wisconsin-Madison. The new facility will provide a dedicated US platform to study innovations in plasma startup techniques, allowing for studies of both HI and RF during plasma initiation, ramp-up and sustainment. Experimental plans for RF heating and current drive in the microwave range of frequencies will be presented. The new capabilities of the Pegasus-III facility will provide a bold test of the viability of a non-solenoidal compact tokamak using reactor relevant techniques.