The National Ignition Facility (NIF): A path to fusion energy

doi:10.1016/j.enconman.2007.10.029

Energy Conversion and Management

Volume 49, Issue 7, July 2008, Pages 1795-1802

https://doi.org/10.1016/j.enconman.2007.10.029 Get rights and content

Abstract

Fusion energy has long been considered a promising, clean, nearly inexhaustible source of energy. Power production by fusion micro-explosions of inertial confinement fusion (ICF) targets has been a long-term research goal since the invention of the first laser in 1960. The National Ignition Facility (NIF) is poised to take the next important step in the journey by beginning experiments researching ICF ignition. Ignition on NIF will be the culmination of over 30 years of ICF research on high-powered laser systems such as the Nova laser at Lawrence Livermore National Laboratory (LLNL) and the OMEGA laser at the University of Rochester, as well as smaller systems around the world. NIF is a 192-beam Nd-glass laser facility at LLNL that is more than 90% complete. The first cluster of 48 beams is operational in the laser bay, the second cluster is now being commissioned, and the beam path to the target chamber is being installed. The Project will be completed in 2009, and ignition experiments will start in 2010. When completed, NIF will produce up to 1.8 MJ of 0.35-μm light in highly shaped pulses required for ignition. It will have beam stability and control to higher precision than any other laser fusion facility. Experiments using one of the beams of NIF have demonstrated that NIF can meet its beam performance goals. The National Ignition Campaign (NIC) has been established to manage the ignition effort on NIF. NIC has all of the research and development required to execute the ignition plan and to develop NIF into a fully operational facility. NIF will explore the ignition space, including direct drive, 2ω ignition, and fast ignition, to optimize target efficiency for developing fusion as an energy source. In addition to efficient target performance, fusion energy requires significant advances in high-repetition-rate lasers and fusion reactor technology. The Mercury laser at LLNL is a high-repetition-rate Nd-glass laser for fusion energy driver development. Mercury uses state-of-the-art technology such as ceramic laser slabs and light diode pumping for improved efficiency and thermal management. Progress in NIF, NIC, Mercury, and the path forward for fusion energy will be presented.

Introduction

Fusion energy can potentially provide a nearly unlimited source of clean sustainable power. Fusion of two light nuclei, normally deuterium and tritium, only occurs in plasmas at elevated temperatures where the particles have sufficient kinetic energy to overcome the Coulomb barrier. Materials cannot survive at these elevated temperatures, thus leading to innovative isolation and containment schemes. Two approaches to containment are magnetic fusion energy in which the fusion plasma is confined by magnetic fields [1] and inertial confinement fusion (ICF) [2] in which the fusion plasma is produced in the core of an imploded spherical capsule. Inertial fusion reactors use high-repetition-rate drivers such as lasers or heavy ion particle beams to produce ICF capsule implosions several times per second [3]. System studies show that reactors will generally operate at repetition rates of 1–20 Hz, targets need a gain of about 100, and the drivers need to be about 10% efficient for commercial power applications. All of these present major challenges for realizing inertial fusion energy (IFE).

The National Ignition Facility (NIF) is preparing to make a significant step forward on one of these challenges [4]. NIF will be the first facility that produces ignition and gain of ICF capsules in the laboratory [5]. Ignition and gain in this context is the production of more fusion energy than the energy used to irradiate the target. NIF will be completed in 2009, and ignition experiments are planned to begin in 2010 as part of the National Ignition Campaign (NIC) that includes all of the required science and technology. These experiments will mark a significant step forward for realizing fusion energy. After the initial ignition experiments, NIF will continue ignition research, optimizing capsule performance as well as exploring alternate approaches such as fast ignitor [6] or direct drive [7] for uses of ignition, including fusion energy. In a complementary effort, LLNL is developing high-repetition-rate Nd lasers as fusion energy drivers. These efforts will position LLNL as a leader in fusion energy development.

Section snippets

National Ignition Facility

The National Ignition Facility (NIF) is a 192-beam laser facility that will produce 1.8 MJ and 500 TW of ultraviolet light for performing ignition target experiments. NIF is the most recent Nd-glass laser constructed at LLNL for ICF research. High-powered lasers have been shown to produce extreme states of matter having high energy density (HED) for studying hydrodynamics, radiative properties and material science at unique laboratory conditions [8]. These studies can provide insight into many

National Ignition Campaign (NIC)

NIF will begin ignition experiments soon after the project is completed with a goal of performing the first experiment in 2010. A significant amount of equipment and technology is required beyond that provided by the project. In addition, understanding the target science and laser performance needs to be refined. A detailed plan called the National Ignition Campaign (NIC) has been developed. The plan includes the target physics and the equipment such as diagnostics, cryogenic target manipulator

Beyond NIC

Beyond the initial ignition experiments, NIF offers the potential to become the world’s premier facility in HED science. With more than 50 times the energy and 10 times the power of present facilities, NIF can produce states of matter not previously available in the laboratory. NIF can accelerate more material for hydrodynamics experiments and heat more mass for radiation transport studies than present facilities. After ignition, the conditions in the hot dense core will be unique in the

High average power lasers

For inertial fusion energy, efficient high-repetition-rate drivers are required. LLNL has a continuing program in developing solid-state lasers for high-repetition-rate applications. The Mercury project is developing laser technology at sub-scale energy and apertures scalable to IFE drivers [18]. The laser shown in Fig. 8 uses diode-pumped, gas-cooled, solid-state slabs for efficient operation. The laser uses eight diode arrays that produce 640 kW at 900 nm with 45% efficiency. They pump slabs of

Acknowledgement

This work was performed under the auspices of the US Department of Energy by the Lawrence Livermore National Laboratory under Contract No. DE-AC52-07NA27344.

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The National Ignition Facility (NIF): A path to fusion energy☆

Abstract

Introduction

Section snippets

National Ignition Facility

National Ignition Campaign (NIC)

Beyond NIC

High average power lasers

Acknowledgement

Opt Commun

The physics of magnetic fusion reactors

Rev Mod Phys

Laser compression of matter to super-high densities: thermonuclear (CTR) applications

Nature

Development of the indirect-drive approach to inertial confinement fusion and the target physics basis for ignition and gain

Phys Plasmas

Ignition and high gain with ultrapowerful lasers

Phys Plasmas

Analysis of a direct-drive ignition capsule designed for the national ignition facility

Phys Plasmas

The science applications of the high-energy density plasmas created on the nova laser

Phys Plasmas