Scalable, Aneutronic-Fusion Energy

Nuclear fusion could provide unlimited, clean-electric power. This vision emerged over a century ago, stimulating engagement of the worldwide scientific and engineering research communities to achieve this goal. Integrated over the past half-century many tens of billions of dollars have been invested worldwide in a multitude concepts studied at national laboratories and fusion companies. These investments have begun to pay off in recent years accelerating the rate of discovery in key areas, as characterized by dramatically increased worlwide government support and private investment.   

A critically important benchmark used to evaluate this progress is measured by "scientific breakeven", where the output energy from the nuclear reaction is compared to the input energy needed to heat the fuel core as a ratio. Recent laser fusion experiments have achieved Q_scientific > 1  and are the example most cited by fusion scientists, investors, and government officials to indicate that fusion works. This example is the only one to date where this benchmark has been attained. 

Nevertheless, two more benchmarks must be achieved and superseded before the deployment of fusion energy will be a  success. "Engineering breakeven"  is a measure of the "total" energy supplied to the reactor in order to sustain the reaction, not just heat the fuel as above  in scientific breakeven. "Economic breakeven"  is a measure of when the total operating cost of producing the output energy is less than the cost of producing it, and preferably when it is cheaper per kW-hr produced that other commercial energy alternatives, for example those based on nuclear fission, fossil fuels, renewables, etc. 

Proponents are often asked when fusion energy will be "on the grid," and the typical response usually ranges from a few years to decades; with the longer timescales being more realistic about the significant obstacles that have yet to  be resolved.  For example, when considering some of the most advanced present designs for fusion power plant concepts some of these unprecedented challenges relate to: 

• the extreme complexity of the reactor and its vulnerability to single-point failures, especially considering the lack of  long duration operational experience in a fusion reactor,  

• an inadequate supply of the nuclear fuel required for operation which is an isotope of hydrogen called tritium and which can only be supplied by a separate nuclear breeding process, the details of which have yet to be established; 

• a radiation- and neutron-flux density at the reactor's "first-wall" that exceeds the damage threshold of all presently known structural materials and that can survive for many years without replacement; 

• public concerns related to a new,  largely untested power source that uses radioactive fuels, produces nuclear pollution, and which has a core energy density 10x larger than any other commercially available nuclear reactor;

• tens of billions of dollars of capital investments, for which the commercial-sector risks are unknown and unprecedented;

• competition from a mix of alternative, and potentially disruptive renewable-energy technologies that have already achieved cost-parity with fossil fuel power sources and are likely to become less expensive in the future. 

Worldwide efforts to address the above issues continues at an accelerating pace, since the potential impact of fusion as a non-polluting, ubiqutious-energy source is difficult to ignore and the payoff for the survival of our planet is critically significant. Nevertheless, one specific approach largely overlooked in this global, nuclear fusion arms race is an alternative approach  based on the use of "aneutronic" fusion fuels that do not produce neutrons. The global supply  of such fuel stocks are abundant and inexpensive. 

Aneutronic fusion could mitigate issues related to the sustainability of the first-wall and derivative reactions that produce "by-product" radioactivity. Moreover, aneutronic fusion could also lead to the development of  scalable designs for the reactor, where the single-unit power output could  potentially be in the range of megawatts (MW) to gigawatts (GW). The availability of small-scale fusion systems could unlock potential applications in transportation, manufacturing, off-grid living,  extraterrestrial environments, etc.; the impact would be  transformative.

Our team is actively pursuing the development of one such approach in a scalable confinement geometry with the plasma  heated by a novel energetic beam approach. We invite potential collaborators to help realize this vision and play a pivotal role in the development of this sustainable approach.