10-Hz beads pellet injection and laser engagement

Laser Inertial Fusion Energy reactor requires repetitive fuel pellet injection and laser engagement to fuse fusion fuel beyond a few Hz. We demonstrate 10 Hz free-fall bead pellets injection and laser engagement with γ-ray generation. Diameter of 1 mm deuterated polystyrene beads were engaged by counter illuminating ultra-intense laser pulses with intensity of 5 x1017 W/cm2 at 10 Hz. The spatial distribution of free-fall beads was 0.86 mm in horizontal, and 0.18 mm in vertical. The system operated beyond 5 minute, 3500 beads supply with achieved frequencies of 2.1 Hz for illumination on bead and 0.7 Hz for γ-ray generation, these frequencies increments three times in relation to the previous 1 Hz injection system. The operation duration was limited by pellet supply. This injection and engagement system can apply for Laser Inertial Fusion Energy research platform.

Prospects for high gain inertial fusion energy: an introduction to the second edition

Part II of this special edition contains the remaining 11 papers arising from a Hooke discussion meeting held in March 2020 devoted to exploring the current status of inertial confinement fusion research worldwide and its application to electrical power generation in the future, via the development of an international inertial fusion energy programme. It builds upon increased coordination within Europe over the past decade by researchers supported by the EUROFusion Enabling Research grants, as well as collaborations that have arisen naturally with some of America's and Asia's leading researchers, both in the universities and national laboratories. The articles are devoted to informing an update to the European roadmap for an inertial fusion energy demonstration reactor, building upon the commonalities between the magnetic and inertial fusion communities’ approaches to fusion energy. A number of studies devoted to understanding the physics barriers to ignition on current facilities are then presented. The special issue concludes with four state-of-the-art articles describing recent significant advances in fast ignition inertial fusion research. This article is part of a discussion meeting issue ‘Prospects for high gain inertial fusion energy (part 2)’.

Factors influencing the commercialization of inertial fusion energy

Managing the IFE pathway to fusion electricity will involve management of commericalization scope, schedule, cost and risk. The technology pathway to economical fusion power comprises the commercialization scope. Industry assumes commercialization risk in fielding its own pre-pilot plant research programme for this compact-fusion pathway without the benefit of a federally coordinated IFE research and development programme. The cost of commercializing the mass-production of inexpensive targets and insisting on high reliability, availability, maintainability and inspectability has a major impact on the economics of commercializing fusion power plants. Schedule vulnerability for inertial fusion energy arises from the sensitivity of time-based roadmap stages to uncertainties in the pace of scientific understanding and technology development, as well as to unexpected and inexplicable changes of the budgeting process. Rather than rely on a time-based roadmap, a milestone-based roadmap is maximally appropriate, especially for industry and investors who are particularly well-suited to taking the risks associated with reaching the target milestones provided by the government. Milestones must be identified and optimally sequenced and the necessary resources must be delineated. Progress on the above factors, since the outcomes of recent U.S., U.K. and EUROfusion roadmapping exercises were released, are reported. This article is part of a discussion meeting issue ‘Prospects for high gain inertial fusion energy (part 2)’.

Prospects for high gain inertial fusion energy: an introduction to the first special edition

A European consortium of 15 laboratories across nine nations have worked together under the EUROFusion Enabling Research grants for the past decade with three principle objectives. These are: (a) investigating obstacles to ignition on megaJoule-class laser facilities; (b) investigating novel alternative approaches to ignition, including basic studies for fast ignition (both electron and ion-driven), auxiliary heating, shock ignition etc.; and (c) developing technologies that will be required in the future for a fusion reactor. The Hooke discussion meeting in March 2020 provided an opportunity to reflect on the progress made in inertial confinement fusion research world-wide to date. This first edition of two special issues seeks to identify paths forward to achieve high fusion energy gain. This article is part of a discussion meeting issue ‘Prospects for high gain inertial fusion energy (part 1)’.

Direct drive with the argon fluoride laser as a path to high fusion gain with sub-megajoule laser energy

Argon fluoride (ArF) is currently the shortest wavelength laser that can credibly scale to the energy and power required for high gain inertial fusion. ArF's deep ultraviolet light and capability to provide much wider bandwidth than other contemporary inertial confinement fusion (ICF) laser drivers would drastically improve the laser target coupling efficiency and enable substantially higher pressures to drive an implosion. Our radiation hydrodynamics simulations indicate gains greater than 100 are feasible with a sub-megajoule ArF driver. Our laser kinetics simulations indicate that the electron beam-pumped ArF laser can have intrinsic efficiencies of more than 16%, versus about 12% for the next most efficient krypton fluoride excimer laser. We expect at least 10% ‘wall plug' efficiency for delivering ArF light to target should be achievable using solid-state pulsed power and efficient electron beam transport to the laser gas that was demonstrated with the U.S. Naval Research Laboratory's Electra facility. These advantages could enable the development of modest size and lower cost fusion power plant modules. This would drastically change the present view on inertial fusion energy as being too expensive and the power plant size too large. This article is part of a discussion meeting issue ‘Prospects for high gain inertial fusion energy (part 1)'.

A simplified economic model for inertial fusion

A simple model for the levelized cost of electricity (LCOE) of an inertial fusion power plant is developed. The model has 14 parameters. These have been designed to be technology agnostic, such that the model may be applied broadly to all variants of inertial fusion. It is also designed to allow easy use of proxies from existing technology. The variables related most intimately to the physics challenges of inertial fusion, such as gain and target cost, are treated as parameters such that requirements can be found without bringing complex physics into the model. A Monte Carlo approach is taken to explore the parameter space. The most important conclusion is that a combination of high gain (greater than 500) and high fusion energy yield per shot (greater than 5 GJ) together appear to unlock more cost competitive designs than those in the existing literature. Designs with LCOE as low as $25/MWh are found with optimistic but not obviously unrealistic inputs. This article is part of a discussion meeting issue ‘Prospects for high gain inertial fusion energy (part 1)'.

Political and commercial prospects for inertial fusion energy

Fusion energy holds the prospect of an energy source that is clean, safe, affordable and limitless. It will transform the global energy system. Today, around $1.5 billion in private capital has been invested in companies that are working on transformative approaches to fusion. Annually, even more than that is spent on fusion research by governments around the world. However, just achieving a scientific demonstration of fusion power will not be enough on its own to transition the global energy system. It will require innovations in the legal, regulatory, commercial and political spheres to support the massive deployment of fusion power that we know will be necessary to meet the global challenges of climate change and energy scarcity. This article is part of a discussion meeting issue ‘Prospects for high gain inertial fusion energy (part 1)'.

Progress and opportunities for inertial fusion energy in Europe

In this paper, I consider the motivations, recent results and perspectives for the inertial confinement fusion (ICF) studies in Europe. The European approach is based on the direct drive scheme with a preference for the central ignition boosted by a strong shock. Compared to other schemes, shock ignition offers a higher gain needed for the design of a future commercial reactor and relatively simple and technological targets, but implies a more complicated physics of laser–target interaction, energy transport and ignition. European scientists are studying physics issues of shock ignition schemes related to the target design, laser plasma interaction and implosion by the code developments and conducting experiments in collaboration with US and Japanese physicists, providing access to their installations Omega and Gekko XII. The ICF research in Europe can be further developed only if European scientists acquire their own academic laser research facility specifically dedicated to controlled fusion energy and going beyond ignition to the physical, technical, technological and operational problems related to the future fusion power plant. Recent results show significant progress in our understanding and simulation capabilities of the laser plasma interaction and implosion physics and in our understanding of material behaviour under strong mechanical, thermal and radiation loads. In addition, growing awareness of environmental issues has attracted more public attention to this problem and commissioning at ELI Beamlines the first high-energy laser facility with a high repetition rate opens the opportunity for qualitatively innovative experiments. These achievements are building elements for a new international project for inertial fusion energy in Europe. This article is part of a discussion meeting issue ‘Prospects for high gain inertial fusion energy (part 1)’.

In-Line Target Production for Laser IFE

The paper presents the results of mathematical and experimental modeling of in-line production of inertial fusion energy (IFE) targets of a reactor-scaled design. The technical approach is the free-standing target (FST) layering method in line-moving spherical shells. This includes each step of the fabrication and injection processes in the FST transmission line (FST-TL) considered as a potential solution of the problem of mass target manufacturing. Finely, we discuss the development strategy of the FST-TL creation seeking to develop commercial power production based on laser IFE.