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The literature on energy technology costs, diffusion, and learning has been characterized by data limitations, partial or arbitrary data sets, apples to oranges comparisons, and imprecision in the use of key concepts and terminology. Two responses to our paper, Lovering et al. (2016), by Koomey et al. and Gilbert et al. reflect many of these problems, conflating learning curves with experience curves, trends in actual costs with the relationship between cost estimates and final construction costs, and component costs with total installed costs. The respondents use inconsistent definitions of demonstration, first-of-a-kind, and commercial deployment across different energy technologies. They also propose to compare final installed costs for nuclear power plants, encompassing construction and finance costs, across different national economies and time periods encompassing a wide range of macro-economic circumstances and finance arrangements that overwhelm any signal from trends associated with the actual construction costs of the plants in question. In this response, we address the specific issues raised in these papers and suggest better practices for comparing energy technology costs, trends, and technological learning.

The existing literature on the construction costs of nuclear power reactors has focused almost exclusively on trends in construction costs in only two countries, the United States and France, and during two decades, the 1970s and 1980s. These analyses, Koomey and Hultman (2007); Grubler (2010), and Escobar-Rangel and Lévêque (2015), study only 26% of reactors built globally between 1960 and 2010, providing an incomplete picture of the economic evolution of nuclear power construction. This study curates historical reactor-specific overnight construction cost (OCC) data that broaden the scope of study substantially, covering the full cost history for 349 reactors in the US, France, Canada, West Germany, Japan, India, and South Korea, encompassing 58% of all reactors built globally. We find that trends in costs have varied significantly in magnitude and in structure by era, country, and experience. In contrast to the rapid cost escalation that characterized nuclear construction in the United States, we find evidence of much milder cost escalation in many countries, including absolute cost declines in some countries and specific eras. Our new findings suggest that there is no inherent cost escalation trend associated with nuclear technology.

Historically, the U.S. has sought to use commercial trade in nuclear technologies to influence international nuclear security standards and promote nonproliferation. Concern has grown that, with a stagnating domestic nuclear industry and declining export industry, the U.S. will lose a significant tool of foreign policy and leverage in maintaining strong international standards. While the issue has been discussed extensively in the policy community and used as a powerful rhetorical tool to motivate tangentially related policies such as subsidizing existing U.S. nuclear plants, no one has systematically assessed the issue, structured the problem and proposed and evaluated potential solutions. Here we briefly analyze the current international state of play, and then outline a set of specific strategies the U.S. might adopt on its own, or promote internationally, to retain its influence. Building on the literature, nuclear security and nuclear power experts assisted us in framing the issues and then, in a participatory workshop, helped us to assess and refine possible strategies. While not all experts agreed that U.S. influence has already declined, most indicated that it likely would decline in the future if present domestic and international trends continue. Although none of the proposed strategies that we advanced or that the experts suggested are likely to be effective in the short term, several warrant ongoing refinements and, if they can be implemented, might have beneficial impacts in coming decades.

© 2016 Elsevier Inc. We discuss two semi-independent calibration techniques used to determine the inflight radiometric calibration for the New Horizons’ Multi-spectral Visible Imaging Camera (MVIC). The first calibration technique compares the measured number of counts (DN) observed from a number of well calibrated stars to those predicted using the component-level calibration. The ratio of these values provides a multiplicative factor that allows a conversation between the preflight calibration to the more accurate inflight one, for each detector. The second calibration technique is a channel-wise relative radiometric calibration for MVIC's blue, near-infrared and methane color channels using Hubble and New Horizons observations of Charon and scaling from the red channel stellar calibration. Both calibration techniques produce very similar results (better than 7% agreement), providing strong validation for the techniques used. Since the stellar calibration described here can be performed without a color target in the field of view and covers all of MVIC's detectors, this calibration was used to provide the radiometric keyword values delivered by the New Horizons project to the Planetary Data System (PDS). These keyword values allow each observation to be converted from counts to physical units; a description of how these keyword values were generated is included. Finally, mitigation techniques adopted for the gain drift observed in the near-infrared detector and one of the panchromatic framing cameras are also discussed.

A l’inverse de Michael Shellenberger (page 28) , les auteurs sont convaincus que seule l’innovation technologique et organisationnelle permettra a l’industrie nucleaire de s’adapter au monde actuel. Face a des energies fossiles bon marche et des energies renouvelables toujours plus accessibles, l’energie nucleaire doit renouer avec la competitivite. Sur le plan technologique, les petits reacteurs, plus rapides a construire, capables de generer des economies d’echelle et d’acquerir rapidement de l’experience, pourraient etre la prochaine rupture technologique. Mais pour que cette innovation devienne realite, les Etats devront faire confiance et soutenir les entrepreneurs et les start-up pour qu’ils developpent les technologies nucleaires innovantes.

We review ongoing efforts to identify occupants of mean-motion resonances (MMRs) and collisional families in the Edgeworth—Kuiper belt. Direct integrations of trajectories of Kuiper belt objects (KBOs) reveal the 1:1 (Trojan), 5:4, 4:3, 3:2 (Plutino), 5:3, 7:4, 9:5, 2:1 (Twotino), and 5:2 MMRs to be inhabited. Apart from the Trojan, resonant KBOs typically have large orbital eccentricities and inclinations. The observed pattern of resonance occupation is consistent with resonant capture and adiabatic excitation by a migratory Neptune; however, the dynamically cold initial conditions prior to resonance sweeping that are typically assumed by migration simulations are probably inadequate. Given the dynamically hot residents of the 5:2 MMR and the substantial inclinations observed in all exterior MMRs, a fraction of the primordial belt was likely dynamically pre-heated prior to resonance sweeping. A pre-heated population may have arisen as Neptune gravitationally scattered objects into trans-Neptunian space. The spatial distribution of Twotinos offers a unique diagnostic of Neptune’s migration history. The Neptunian Trojan population may rival the Jovian Trojan population, and the former’s existence is argued to rule out violent orbital histories for Neptune. Finally, lowest-order secular theory is applied to several hundred non-resonant KBOs with well-measured orbits to update proposals of collisional families. No convincing family is detected.

The Afton Mines SAG circuit was sampled to develop a circuit simulator. Methodology employed to obtain preliminary models is described. Models were connected together to simulate the circuit. A preliminary analysis of output is included in discussion of results.