[en] The economic prospects for magnetic fusion energy can be dramatically improved if for the same total power output the fusion neutron first-wall (FW) loading and the system power density can be increased by factors of 3 to 5 and 10 to 30, respectively. A number of compact fusion reactor embodiments have been proposed, all of which would operate with increased FW loadings, would use thin (0.5 to 0.6 m) blankets, and would confine quasi-steady-state plasma with resistive, water-cooled copper or aluminum coils. Increased system power density (5 to 15 MWt/m³ versus 0.3 to 0.5 MW/m³), considerably reduced physical size of the fusion power core (FPC), and appreciably reduced economic leverage exerted by the FPC and associated physics result. The unique materials requirements anticipated for these compact reactors are outlined against the well documented backdrop provided by similar needs for the mainline approaches. Surprisingly, no single materials need that is unique to the compact systems is identified; crucial uncertainties for the compact approaches must also be addressed by the mainline approaches, particularly for in-vacuum components (FWs, limiters, divertors, etc.)

[en] A behavioral, top-down, forced-equilibrium market model of long-term (∼ 2,100) global energy-economics interactions has been modified with a bottom-up nuclear energy model and used to construct consistent scenarios describing future impacts of civil nuclear materials flows in an expanding, multi-regional (13) world economy. The relative measures and tradeoffs between economic (GNP, tax impacts, productivity, etc.), environmental (greenhouse gas accumulations, waste accumulation, proliferation risk), and energy (resources, energy mixes, supply-side versus demand-side attributes) interactions that emerge from these analyses are focused herein on advancing understanding of the role that nuclear energy (and other non-carbon energy sources) might play in mitigating greenhouse warming. Two ostensibly opposing scenario drivers are investigated: (a) demand-side improvements in (non-price-induced) autonomous energy efficiency improvements; and (b) supply-side carbon-tax inducements to shift energy mixes towards reduced- or non-carbon forms. In terms of stemming greenhouse warming for minimal cost of greenhouse-gas abatement, and with the limitations of the simplified taxing schedule used, a symbiotic combination of these two approaches may offer advantages not found if each is applied separately

[en] A cost-based parametric systems model is developed for an Accelerator-Driven Energy Production (ADEP) system based on a ²³²Th/²³³U fuel cycle and a molten-salt (LiF/BeF₂/ThF₃) fluid-fuel primary system. Simplified neutron-balance, accelerator, reactor-core, chemical-processing, and balance-of-plant models are combined parametrically with a simplified costing model. The main focus of this model is to examine trade offs related to fission power density, reactor-core modularity, ²³³U breeding rate, and fission product transmutation capacity

[en] The fusion burn dynamics and energy yield of the dense Z-pinch (DZP) are examined using a profile-averaged, zero-dimensional, time dependent model. A range of conditions (fuel, line density, voltage, fusion-product heating, enthalpy endloss, density and temperature profiles, current rise rate, electrode impurities) are examined. Magneto-hydrodynamic stability is assumed, and initial conditions are based on those ideally existing after the melting and ionization of a solid fiber of fusion fuel. Plasma conditions required of neutron sources for materials testing (S_n ≥ 10¹⁹ n/s) and for possible commercial power production (ratio of fusion energy yield to energy input, Q_p ≅ 15, lower values if reversible recovery of a fraction of the magnetic energy is possible) are described. If f_B approx-gt 0.8 fractional fuel burnup is possible in a nominal 800-ns DT discharge (200-ns current-rise phase at 20 MV/m followed by a 500-ns constant-current crowbarred phase), reactor-relevant values of Q_p may be possible. For the simpler (and shorter) constant-voltage discharge (e.g., no voltage crowbar) the value of Q_p is in the range 5--10 for discharges below 200-ns duration. Smaller levels of fuel burnup, shorter discharges, or generally lower levels of Q_p will require a reversible energy transfer system to meet reactor energy-balance requirements. Imposition of a plasma current rise-time constraint that may be needed for stable plasma operation (e.g., I > 10¹² A/s) will burnup, Q_p and discharge time to an extent where reversible energy/transfer system will be required to meet reactor energy- balance requirements. 25 refs

[en] An almost primordial trend in the conversion and use of energy is an increased complexity and cost of conversion systems designed to utilize cheaper and more-abundant fuels; this trend is exemplified by the progression fossil fission → fusion. The present projections of the latter indicate that capital costs of the fusion ''burner'' far exceed any commensurate savings associated with the cheapest and most-abundant of fuels. These projections suggest competitive fusion power only if internal costs associate with the use of fossil or fission fuels emerge to make them either uneconomic, unacceptable, or both with respect to expensive fusion systems. This ''implementation-by-default'' plan for fusion is re-examined by identifying in general terms fusion power-plant embodiments that might compete favorably under conditions where internal costs (both economic and environmental) of fossil and/or fission are not as great as is needed to justify the contemporary vision for fusion power. Competitive fusion power in this context will require a significant broadening of an overly focused program to explore the physics and simbiotic technologies leading to more compact, simplified, and efficient plasma-confinement configurations that reside at the heart of an attractive fusion power plant

[en] The promise and problems of Linear Magnetic Fusion (LMF) for the generation of electrical power are surveyed. A number of axial confinement schemes are described and compared on an n tau basis. Likewise, the range of heating methods is described. The results of seven conceptual LMF reactor design studies are summarized with an emphasis on the interfaces between reactor operation, confinement scheme, and heating methods

[en] The utilization of deuterium-based fuels offers the potential advantages of greater flexibility in blanket design, significantly reduced tritium inventory, potential reduction in radioactivity level, and utilization of an inexhaustible fuel supply. The conventional DT-fueled Reversed-Field Pinch Reactor (RFPR) designs are reviewed, and the recent extension of these devices to advanced-fuel (catalyzed-DD) operation is presented. Attractive and economically competitive DD/RFPR systems are identified having power densities and plasma parameters comparable to the DT systems. Converting an RFP reactor from DT to DD primarily requires increasing the magnetic field levels a factor of two, still requiring only modest magnet coil fields (less than or equal to 4 T). When compared to the mainline tokamak, the unique advantages of the RFP (e.g., high beta, low fields at the coils, high ohmic-heating power densities, unrestricted aspect ratio) are particularly apparent for the utilization of advanced fuels

[en] A global energy/economics/environmental (E³) model has been adapted with a nuclear energy/materials model to understand better open-quotes top-levelclose quotes, long-term trade offs between civilian nuclear power, nuclear-weapons proliferation, fossil-fuel burning, and global economic welfare. Using a open-quotes business-as-usualclose quotes (BAU) point-of-departure case, economic, resource, proliferation-risk implications of plutonium recycle in LAIRs, greenhouse-gas-mitigating carbon taxes, and a range of nuclear energy costs (capital and fuel) considerations have been examined. After describing the essential elements of the analysis approach being developed to support the Los Alamos Nuclear Vision Project, preliminary examples of parametric variations about the BAU base-case scenario are presented. The results described herein represent a sampling from more extensive results collected in a separate report. The primary motivation here is: (a) to compare the BAU basecase with results from other studies; (b) to model on a regionally resolved global basis long-term (to year ∼2100) evolution of plutonium accumulation in a variety of forms under a limited range of fuel-cycle scenarios; and (c) to illustrate a preliminary connectivity between risks associated with nuclear proliferation and fossil-fuel burning (e.g., greenhouse-gas accumulations)

[en] This paper discusses the feasibility of reversed-field pinch devices as future thermonuclear reactors. Safety, cost, ion temperatures, Lawson numbers, and power densities are reviewed for these types of devices. 12 refs., 2 figs., 1 tab

[en] A parametric systems model of the ATW [Accelerator Transmutation of (Nuclear) Waste] has been used to examine key system tradeoffs and design drivers on the basis of unit costs. This model has been applied primarily to the aqueous-slurry blanket concept for an ATW that generates net-electric power from the fissioning of spent reactor fuel. An important goal of this study is the development of essential parametric tradeoff studies to aid in any eventual engineering design of an ATW that would burn and generate net- electric power from spent reactor fuel