By Scott Hsu, Scientist at Los Alamos National Laboratory July 12, 2016
Challenges at ITER and the National Ignition Facility (NIF) bolster the quip that fusion is always thirty years away. This is increasingly bringing into question fusion’s “monoculture” (e.g., see Dan Clery’s editorial, Dec. 2014). Because renewable and fission energy are being deployed, despite their limitations, fusion is not regarded as urgent. Thus, overall government funding of fusion is unlikely to increase anytime soon. If fusion is to penetrate midcentury power-generation markets and improve our chances of meeting mid- and late-century carbon-emission targets, more approaches are needed.
While mainstream fusion approaches, as represented by ITER and NIF, are the most scientifically mature, there are also many scientifically credible alternative fusion concepts. Most have benefitted from government funding over several decades. Alternative concepts typically have less engineering complexity through the use of more efficient plasma confinement, assembly, and/or compression technologies. While many concepts are now known to have performance limits justifying their lower priority today, others lost support prematurely and/or have enjoyed recent advances to warrant further study. Some of these concepts, e.g., magneto-inertial fusion [now supported by the ARPA-E ALPHA Program of the U.S. Department of Energy (DOE)], have the potential to significantly lower the cost and shorten the timeline of fusion-energy development, even though they are presently less mature than the mainstream approaches.
There is relatively little government funding in the U.S. and other countries for developing alternative fusion concepts. This situation is, at least in part, fueling private investments in fusion energy, e.g., Tri Alpha Energy, General Fusion, Tokamak Energy, Helion Energy, and First Light Fusion, indicating that some investors and researchers are willing to tackle both early-stage and more-mature alternative fusion concepts on their own, despite billions of dollars per year spent by governments on mainstream fusion. It also signifies both opportunities in alternative fusion and frustrations with the progress and promise of the mainstream approaches, which appear to have focused on minimizing scientific risk while exposing themselves to huge risks in funding, schedule, engineering, politics, and public perception.
It bears asking how we might best harness and grow private investments in fusion. Investors normally back a specific technology and team. To fit this model, entrepreneurial fusion researchers may be pressured to down-select on technical options before the science fully justifies their choices, thereby increasing risk to both themselves and their investors. Broader government support of alternative fusion-concept development is the logical way to potentially give us a greater number of lower-cost development options at a more attractive risk-reward ratio. This could unlock even more private-investment dollars. In addition, fusion development would greatly benefit from private ventures being allowed to utilize government-supported computational capabilities and nuclear-qualified test sites.
With even the lowest-cost, credible alternative fusion approaches likely to cost billions of dollars to realize a grid-ready reactor, innovation is needed in how to fund fusion development as much as in solving its technical challenges. We encourage leading energy-sector investors, e.g., the Breakthrough Energy Coalition, to innovate in funding models for fusion development. The objective should be to enable a viable public-private partnership to develop fusion energy in time to penetrate midcentury power-generation markets.
This article draws upon the author’s testimony on US-DOE support of innovative fusion concept development in a hearing on fusion energy science (on April 20, 2016) held by the Energy Subcommittee of the U.S. House Committee on Science, Space, and Technology. This article represents the author’s opinions and not necessarily those of his employer nor research sponsors.