William J. Hogan

Energy from Inertial Fusion

Fusion is potentially a safe clean source not limited by political boundaries. Magnetic and inertial fusion share this promise, but there are differences between them. An inertial fusion power plant is based on different physics and technology from a magnetic fusion power plant and therefore presents somewhat different benefits and challenges. The facilities required to demonstrate inertial fusion power are potentially much smaller. In this article we describe concepts for such a power plant, its beneficial features and a low‐cost reactor test facility for developing practical fusion power.

The National Ignition Facility

The National Ignition Facility (NIF) is the largest construction project ever undertaken at Lawrence Livermore National Laboratory (LLNL). The NIF consists of 192 40 cm square laser beams and a 10 m diameter target chamber. The NIF is being designed and built by an LLNL led team from Los Alamos National Laboratory, Sandia National Laboratories, the University of Rochester and LLNL. Physical construction began in 1997. The Laser and Target Area Building and the Optics Assembly Building were the first major construction activities, and despite several unforeseen obstacles, the buildings are now 92% complete and have been built on time and within cost. Prototype component development and testing has proceeded in parallel. Optics vendors have installed full scale production lines and have performed prototype production runs. The assembly and integration of the beampath infrastructure have been reconsidered and a new approach has been developed. The article discusses the status of the NIF project and the plans for completion.

The National Ignition Facility - applications for inertial fusion energy and high-energy-density science

Over the past several decades, significant and steady progress has been made in the development of fusion energy and its associated technology and in the understanding of the physics of high-temperature plasmas. While the demonstration of net fusion energy (fusion energy production exceeding that required to heat and confine the plasma) remains a task for the next millennia and while challenges remain, this progress has significantly increased confidence that the ultimate goal of societally acceptable (e.g. cost, safety, environmental considerations including waste disposal) central power production can be achieved. This progress has been shared by the two principal approaches to controlled thermonuclear fusion--magnetic confinement (MFE) and inertial confinement (ICF). ICF, the focus of this article, is complementary and symbiotic to MFE. As shown, ICF invokes spherical implosion of the fuel to achieve high density, pressures, and temperatures, inertially confining the plasma for times sufficient long (t {approx} 10{sup -10} sec) that {approx} 30% of the fuel undergoes thermonuclear fusion.

Fusion Reactor Design IV (Report on the 4th IAEA Technical Committee Meeting and Workshop, Yalta, USSR, 26 May – 6 June 1986)

The International Atomic Energy Agency convened, in the framework of its Fusion Technology and Engineering Programme, the 4th Technical Committee and Workshop on Fusion Reactor Design and Technology at Yalta, USSR, from 26 May – 6 June 1986. This report contains all summaries of sessions that were organized during the workshop. The papers presented at the meeting are being published by the Agency in its Proceedings Series.

Advances in ICF power reactor design

Fifteen ICF power reactor design studies published since 1980 are reviewed to illuminate the design trends they represent. There is a clear, continuing trend toward making ICF reactors inherently safer and environmentally benign. Since this trend accentuates inherent advantages of ICF reactors, we expect it to be further emphasized in the future. An emphasis on economic competitiveness appears to be a somewhat newer trend. Lower cost of electricity, smaller initial size (and capital cost), and more affordable development paths are three of the issues being addressed with new studies.

Economic studies for heavy‐ion‐fusion electric power plants

We have conducted parametric economic studies for heavy‐ion‐fusion electric power plants. We examined the effects on the cost of electricity of several design parameters: cost and cost scaling for the reactor, driver, and target factory; maximum achievable chamber pulse rate; target gain; electric conversion efficiency; and net electric power. Using the most recent estimates for the heavy‐ion‐driver cost along with the Cascade reactor cost and efficiency, we found that a 1.5 to 3 GWe heavy‐ion‐fusion power plant, with a pulse rate of 5–10 Hz, can be competitive with nuclear and coal power plants.

Results of 40-m3 LNG Spills onto Water

Lawrence Livermore National Laboratory (LLNL) is conducting safety research under the sponsorship of the U.S. Department of Energy (DOE) to determine the possible consequences of liquefied natural gas (LNG) spills. The LLNL program includes both the collection of data from various size experiments and development of an ensemble of computer models to make predictions for conditions under which tests cannot be performed. In spills of 40 cubic metres (m3) of LNG onto water done at the Naval Weapons Center (NWC), China Lake, California in 1980 and 1981, data was collected on gas cloud dispersion and combustion and rapid phase transition (RPT) explosions. Analysis of the data from these tests, including comparisons between the predictions of various models and the data, are presented. The results suggest that largescale spills may be more hazardous than would have been predicted based on earlier small-scale tests. Work performed under the auspices of the U.S. Department of Energy by the Lawrence Livermore National Laboratory under contract number W-7405-ENG-48.

Inertial fusion science and technology for the 21 st century

Abstract This paper reviews the leading edge of the basic and applied science that use high-intensity facilities. The more than 15 000 experiments on the Nova laser since 1985 and many thousands more on other laser, particle beam, and pulsed power facilities around the world have established the new laboratory field of high-energy-density plasma physics and have furthered development of inertial fusion. High-brightness femtosecond lasers have enabled the study of matter in conditions previously unachievable on earth. These experiments and advanced calculations have established the specifications for the National Ignition Facility (NIF) and Laser MegaJoule (LMJ) and have enhanced scientific fields such as laboratory astrophysics. Science and technology developed in inertial fusion have found near-term commercial use, have enabled steady progress toward the goal of fusion ignition and gain in the laboratory, and have opened up new fields of study for the 21 st century.

A lower-cost development path for heavy-ion fusion

SummaryIf two features of the inertial-fusion process are exploited success-fully, they can lead to significantly lower costs for demonstrating the feasibility of commercial electric power production from this source of energy. First, fusion capsule ignition and burn physics are independent of reaction chamber size and hydrodynamically equivalent capsules can be designed to perform at small yield, exactly as they do at large yield. This means that an integrated test of all power plant components and feasibility tests of various reaction chamber concepts can be done at much smaller sizes (about 1–2 m first wall radius) and much lower powers (tens of MWs) than magnetic fusion development facilities such as ITER. Second, the driver, which is the most expensive component of currently conceived IFE development facilities, can be used to support more than one experimental target chamber/reactor (simultaneously and/or sequentially). These two factors lead to lower development facility costs, modular facilities, and the planning flexibility to spread costs over time or do several things in parallel and thus shorten the total time needed for development of inertial fusion energy (IEE). In this paper we describe the general features of heavy-ion fusion development plant that takes advantage of upgradable accelerators and the ability to test chambers and reactor systems at small scale in order to reduce development time and costs.

Inertial fusion energy development beyond 2000

ConclusionsUltimately, of course, a prototype power plant will be built at a power level appropriate for planned future commercial operations. This could use the same ETF/ DPP driver or a new one tailored to the plant size and with less experimental flexibility than the ETF driver. With the experience and data gained from a number of small demonstration reactors, and from the operation of the ETF/DPP driver and target factory, it is quite likely that a variety of plant sizes options will be available at that time.The scenario explored here is a relatively low-cost development program for fusion energy, which encourages technology transfer to American industry at an early stage. If the government builds an ETF driver, target factory, a single-shot experiment area, and a burst mode facility, commercial companies may be interested in building their own small demonstration reactors which would be supported by the government facilities. The fact that the ETF and any number of DPPs could be supported by the same driver and target factory means that the incremental cost of trying many alternatives is small. The fact that IFE demonstration reactors can test all relevant parameters at low power means that IFE has no extremely high-cost (multi-billion dollar) development facility to build in order to demonstrate engineering feasibility, i.e., there is no large development “hurdle” to surmount. We can, indeed, start small and work our way larger as the results justify. The result of this approach may produce competitive IFE power plant designs from a few to a few thousand megawatts.