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This presentation focuses on a renewable energy future. It outlines100% clean energy by 2035 scenarios, unique and wind grand challenges, adding that digitalization in the form of hardware, data, and 21st century software solutions will be critical in meeting these goals., {"references":["Denhold, Brown et al. 100% by 2035 https://www.nrel.gov/docs/fy22osti/81644.pdf"]}

The wind generation share in many European bidding zones is now large enough to affect the market value of wind power, and wind energy is getting less-than-average market price in day-ahead markets. As alternatives to investing in dedicated energy storage, there are two main ways to mitigate the decreasing market value trend. The first is employing different diversification measures (geographical spread, alternative wind turbine technologies, integration with solar). The second is implementing demand flexibility measures. Examples of these measures from some European and USA studies are given in this article, which stems from the international collaboration under IEA Wind TCP Tasks 25 and 53. Improving wind power market value with various aspects of diversification

Experimental demonstrations of entangled quantum images produced through parametric downconversion have so far been confined to studying two photon correlations. Here we show that multiphoton correlations between quantum images are accessible experimentally and exhibit many new features including being sensitive to the phase of the bi-photon wavefunction. As a concrete example, we consider a modification of existing quantum imaging experiments in which the CCD cameras are moved out of focus, provide detailed analytical predictions for the resulting 4 photon intereferences, and support these by numerical simulations. The proposed experiment can also be interpreted as entanglement swapping: Bob's photons are initially unentangled, but the joint detection of Alice's photons projects Bob's photons onto an entangled state. The general approach proposed here can be extended to other quantum optics experiments involving high dimensional entanglement., Comment: 13 pages, 3 figures

Mounting interest in ambitious clean energy goals is exposing critical gaps in our understanding of onshore wind power potential. Conventional approaches to evaluating wind power technical potential at the national scale rely on coarse geographic representations of land area requirements for wind power. These methods overlook sizable spatial variation in real-world capacity densities (i.e. nameplate power capacity per unit area) and assume that potential installation densities are uniform across space. Here, we propose a data-driven approach to overcome persistent challenges in characterizing localized deployment potentials over broad extents. We use machine learning to develop predictive relationships between observed capacity densities and geospatial variables. The model is validated against a comprehensive data set of U.S. wind facilities and subjected to interrogation techniques to reveal that key explanatory features behind geographic variation of capacity density are related to wind resource as well as urban accessibility and forest cover. We demonstrate application of the model by producing a high-resolution (2 km x 2 km) national map of capacity density for use in technical potential assessments for the United States. Our findings illustrate that this methodology offers meaningful improvements in the characterization of spatial aspects of technical potential, which are increasingly critical to draw reliable and actionable planning and research insights from renewable energy scenarios.

This paper compares the 95% upper limit on the signal level between 2 estimators: the cross-spectrum and the spectrum average. This is generalized in the case where we have more than 2 radio-telescopes and an example is given in the case of 5 radio-telescopes.

International audience; We report the experimental observation of a spatiotemporal Hong-Ou-Mandel (HOM) interference of biphoton states of extremely high Schmidt number. Two-photon interference of 1500 spatial modes and a total of more than 3×106 spatiotemporal modes is evidenced by measuring momentum spatial coincidences, without any prior selection of the photons in time and space coincidence, between the pixels of the far-field images of two strongly multimode spontaneous parametric down-conversion (SPDC) beams propagating through a HOM interferometer. The outgoing SPDC beams are recorded on two separate detector arrays operating in the photon-counting regime. The properties of HOM interference are investigated both in the time and space domains. We show that the two-photon interference exhibits temporal and two-dimensional spatial HOM dips with visibilities of 60% and widths in good agreement with the spatiotemporal coherence properties of the biphoton state. Moreover, we demonstrate that maxima of momentum spatial coincidences are evidenced within each image, in correspondence with these dips.

We first extend our recent experiments of correlation imaging through scattering media to the case of a thick medium, composed of two phase scatterers placed respectively in the image and the Fourier planes of the crystal. The spatial correlations between twin photons are still detected but no more in the form of a speckle. Second, a numerical simulation of the biphoton wave function is developed and applied to our experimental situation, with a good agreement.

We report the experimental observation of a spatio-temporal Hong-Ou-Mandel (HOM) interference of bi-photon states of extremely high Schmidt number. Two-photon interference of 1500 spatial modes and a total of more than 3x10^6 spatio-temporal modes is evidenced by measuring momentum spatial coincidences between the pixels of the far-field images of two strongly multimode spontaneous parametric down conversion (SPDC) beams propagating through a HOM interferometer. The outgoing SPDC beams are recorded onto two separate detectors arrays operating in the photon-counting regime. The properties of HOM interference are investigated both in the time and space domains. We show that the two-photon interferences exhibit temporal and two-dimensional spatial HOM dips with visibilities of 30% and widths in good agreement with the spatio-temporal coherence properties of the bi-photon state. Moreover, we demonstrate that a peak of momentum spatial coincidences is evidenced inside each image, in correspondence with this dip., Comment: 10 pages, 8 figures

International audience; We report photon-counting imaging of entangled photon-pairs of high Schmidt number transmitted through a scattering medium. We demonstrate that spatial momentum or position quantum correlations, measured between twin images recorded on two separate detectors, exhibit in both cases speckle patterns. Moreover, the total correlation is only slightly lowered by scattering.

International audience; We report results of quantum holography (QH) where spatial informations stored in phase holograms are retrieved by measuring spatial coincidences between two images formed by spatially entangled twin photons of high-dimensionality. For the two setup configurations reported here, spatial informations are retrieved when holograms are read either with both photons or with one photon of the bi-photon states.

International audience; We report photon-counting imaging of entangled photon-pairs of high Schmidt number transmitted through a scattering medium lying either in the near-field or in the far-field of the entangled photons source. We demonstrate that spatial momentum or position quantum correlations, measured between twin images recorded onto two separate detectors, exhibit in both cases speckle patterns. Moreover, the total correlation is only slightly lowered by the scattering.

This paper draws on a survey of wind industry professionals to clarify trends in the operational expenditures (OpEx) of U.S. land-based wind power plants. The paper also highlights key drivers of those trends. We find that average all-in lifetime OpEx has declined from approximately $80/kW-yr ( $35/MWh) for projects built in the late 1990s to a level that is approaching $40/kW-yr ( $11/MWh) for projects under construction in 2018. Turbine operations and maintenance (O&M) costs—inclusive of scheduled and unscheduled maintenance—represent the single largest component of overall OpEx and the primary source of cost reductions over the last decade. We observe wide ranges of OpEx over time; for example, survey respondents cite a range in average expected costs for projects commissioned between 2015 and 2018 from $33/kW-yr to $59/kW-yr. Notably, these broad ranges include high levels of variability in both turbine O&M costs and non-turbine OpEx. Potential technical and strategic drivers of this variability are highlighted. We also use historical OpEx learning rates, showing a 9% OpEx reduction for each doubling of global installed wind capacity, to project a further $5–$8/kW-yr (12%–18%) OpEx reduction from 2018 to 2040. When compared with the broader literature, these findings suggest that continued OpEx reductions may contribute 10% or more of the expected reductions in land-based wind’s levelized cost of energy. Moreover, these estimates may understate the importance of OpEx owing to the multiplicative effects through which operational advancements influence not only O&M costs but also component reliability, performance, and plant-level availability—thereby affecting levelized costs though OpEx reduction and by enhancing annual energy production and plant lifetimes. Given the limited quantity and comparability of previously available OpEx data, the data and trends reported here may usefully inform OpEx assumptions used by electric system planners, analysts, modelers, and research and development managers. The results may also provide useful benchmarks to the wind industry, helping developers and asset owners compare their OpEx expectations with historical experience and other industry projections.

We image with cameras entangled photon light transmitted through a random medium. Near-field and far-field spatial quantum correlations show that entangled photon pairs (bi-photons) generated by spontaneous optical parametric down-conversion exhibit speckle pattern. In contrast, no information from the random medium can be extracted using incoherent light issued from one photon of the pair. Although these measurements require several hours to record thousands of image pairs, our method is instantaneous for the recording of one pair of twin images and involve all the photons of the images.

The wind industry has realized substantial growth reaching over 500 gigawatts (0.5 terawatts) of installed capacity in 2017 (Global Wind Energy Council 2018) and producing about 5% of global electricity demand in 2016 (Wiser and Bolinger 2018). The levelized cost of energy (LCOE) for wind energy projects both on land and offshore has fallen as a result of substantial innovation over the last several decades. More specifically, equipment, installation, and operation costs have decreased while energy production per turbine has increased (Wiser et al. 2016). At the same time as LCOE has been decreasing, integration challenges in the broader electric system have been successfully addressed in many markets, thereby enabling the level of wind energy generation to grow to more than 10% of electricity consumption in at least eight countries around the world and more than 30% in Portugal and Denmark (Wiser and Bolinger 2018).

International audience

International audience

International audience; Nous présentons les résultats expérimentaux de la restitution d’un hologramme de phase par la mesure de corrélations quantiques spatiales entre des paires de photons intriqués (biphotons) avec une dimensionnalité spatiale d’environ 1800. Ces biphotons, générés par émission paramétrique spontanée dans un cristal non linéaire, sont transmis à travers un hologramme de phase. Les photons jumeaux sont ensuite détectés en champ lointain séparément sur 2 caméras EMCCD. La restitution de l’information contenue dans l’hologramme de phase est finalement obtenue en mesurant la répartition des coïncidences spatiales d’origine quantique entre les images jumelles.

We report results of two-photon quantum holography where spatial information stored in phase holograms is retrieved by measuring quantum spatial correlations between two images formed by spatially entangled twin photons with a dimensionality of 1790 in the two-dimensional transverse space. In our experiments, the entire flux of spontaneous down converted photons illuminates the phase holograms and the photons of pairs signal-idler transmitted by the holograms are detected separately in far field on two electron-multiplying charge coupled device cameras., 6 pages, 4 figures

National audience; &nbsp

International audience

National audience; Nous présentons un dispositif expérimental très simple d’imagerie fantôme permettant la détection d’un signal temporel avec un détecteur ne présentant pas de résolution temporelle. La reconstruction du signal fantôme est assurée par la mesure unique et spatialement multiplexée de corrélations d’intensité entre une base d’images aléatoires et indépendantes et les mêmes images modulées par le signal temporel et intégrées dans le temps par une caméra sans résolution temporelle.

National audience; Nous avons mis en place une expérience d’imagerie fantôme temporelle utilisant les propriétés de faisceaux corrélés spatialement. Cette expérience montre qu’il est possible de reconstruire un signal temporel unique et non périodique, acquis au moyen d’une caméra intégrant entièrement le signal, c’est-à-dire sans résolution temporelle.

International audience; We report on an application of a three-dimensional pseudospectral time-domain algorithm that solves with accuracy the nonlinear Maxwell’s equations so as to predict second-harmonic generation in lithium niobate ridge-type waveguides with high index contrast. Characteristics of the nonlinear process such as conversion efficiency and impact of the multimode character of the waveguide are investigated as a function of the waveguide geometry in uniformly and periodically poled media.

International audience; We report on an application of a three-dimensional pseudospectral time-domain algorithm that solves with accuracy the nonlinear Maxwell’s equations so as to predict second-harmonic generation in lithium niobate ridge-type waveguides with high index contrast. Characteristics of the nonlinear process such as conversion efficiency and impact of the multimode character of the waveguide are investigated as a function of the waveguide geometry in uniformly and periodically poled media.

National audience; &nbsp

We initiate the study of privacy in pharmacogenetics, wherein machine learning models are used to guide medical treatments based on a patient’s genotype and background. Performing an in-depth case study on privacy in personalized warfarin dosing, we show that suggested models carry privacy risks, in particular because attackers can perform what we call model inversion: an attacker, given the model and some demographic information about a patient, can predict the patient’s genetic markers.

International audience; Spatially entangled twin photons provide both promising resources for modern quantum information protocols, because of the high dimensionality of transverse entanglement, and a test of the Einstein-Podolsky-Rosen paradox in its original form of position versus impulsion. Usually, photons in temporal coincidence are selected and their positions recorded, resulting in a priori assumptions on their spatiotemporal behavior. In this Letter, we record, on two separate electron-multiplying charge coupled devices cameras, twin images of the entire flux of spontaneous down-conversion. This ensures a strict equivalence between the subsystems corresponding to the detection of either position (image or near-field plane) or momentum (Fourier or far-field plane). We report the highest degree of paradox ever reported and show that this degree corresponds to the number of independent degrees of freedom, or resolution cells, of the images.

With a small number of measurements, the three most well known estimators of a single parameter give very different results when estimating a scale parameter. A transformation of this scale parameter to a location parameter by using logarithms of the data rends the three estimators equivalent in the absence of any a priori information., Comment: 8 pages, 1 figure

Replaced with revised version of poster 07/07/11.

We model the marginal impacts of wind turbine development on county-level changes in per capita income and employment in 15 states from 2000 to 2008. Using propensity score matching and spatial econometric techniques, we find that the total marginal impact on per capita income of wind turbine development (measured in MW per capita) when controlling for spatial effects was statistically significant with a value of $21,604 per MW. This estimate is within the range of values estimated in the literature using input-output models. Our ex post estimates of employment impacts are not precise enough to inform the validity of ex ante employment impacts from input-output models., Replaced with revised version of poster 07/07/11.

International audience; The principle of operation of fibre optical parametric amplifiers is revisited with a special attention to the pump wave characteristics ranging from the monochromatic coherent case to the incoherent one.

This dissertation presents an experimental study of spatial quantum fluctuations of light in optical parametric amplification (OPA). First, we characterize the response of a CCD camera for the measurement of the spatial shot noise in the image transverse plane. We show the high capabilities of silicon arrays for the visible domain (527 nm) contrary to its bad response in the near IR domain (1055 nm). Then, we use a calibration method of the sensitivity of pixels to eliminate inhomogeneities and to retrieve shot noise for high and low intensity levels. Next, we study the quantum aspects of OPA. The best experimental solution is to amplify a shot noise limited image (527 nm) by a UV pump (264 nm) in a type I BBO cristal. We define an experimental scheme and a protocol of measurement to compare the phase sensitive amplification scheme (PSA) and the phase insensitive amplification scheme (PIA). For the PIA case, we show the degradation of the signal to noise ratio. And for the PSA case, we achieved the first spatially noiseless amplification of images. For both cases, experimental values are in good agreement with theoretical noise figure. Moreover, we study the spatial fluctuations of parametric fluorescence. Using short pulses combined with a narrow spectral filter, we directly characterize a pure distribution of Bose-Einstein; Ce mémoire présente une étude expérimentale des fluctuations spatiales d'origine quantique de l'intensité dans des images en amplification paramétrique optique (OPA). Dans un premier temps nous avons caractérisé la réponse d'une caméra CCD lors de la mesure du bruit de photons dans le plan transverse de l'image. Pour cela, nous avons montré la pleine aptitude des capteurs silicium pour le domaine visible (527 nm) et leur mauvaise réponse dans le proche IR (1055 nm). Puis nous avons calibré le capteur sur toute sa dynamique afin d'éliminer l'inhomogénéité de réponse des pixels et ainsi mesurer le bruit de photons dans des images faibles ou intenses. D'autre part, nous avons étudié les aspects quantiques des OPA. L'amplification à l'aide d'un cristal de BBO de type I d'images (527 nm) dominées par le bruit quantique à l'aide d'une pompe UV (264nm) s'est imposée comme le meilleur compromis expérimental. Nous avons mis au point un montage et un protocole de mesure permettant la comparaison entre l'amplification sensible à la phase (PSA) et l'amplification insensible à la phase (PIA). Dans le cas d'une PIA, nous avons mis en évidence la dégradation du rapport signal à bruit. Pour la configuration PSA, nous avons réalisé la première amplification paramétrique d'images sans bruit spatial. Pour ces deux cas, les valeurs expérimentales sont en accord avec la figure de bruit attendue. De plus, nous avons étudié la distribution des fluctuations spatiales de la fluorescence paramétrique. L'emploi d'impulsions brèves et un fort filtrage des longueurs d'onde ont permis la caractérisation directe de la distribution de Bose-Einstein pure.

This dissertation presents an experimental study of spatial quantum fluctuations of light in optical parametric amplification (OPA). First, we characterize the response of a CCD camera for the measurement of the spatial shot noise in the image transverse plane. We show the high capabilities of silicon arrays for the visible domain (527 nm) contrary to its bad response in the near IR domain (1055 nm). Then, we use a calibration method of the sensitivity of pixels to eliminate inhomogeneities and to retrieve shot noise for high and low intensity levels. Next, we study the quantum aspects of OPA. The best experimental solution is to amplify a shot noise limited image (527 nm) by a UV pump (264 nm) in a type I BBO cristal. We define an experimental scheme and a protocol of measurement to compare the phase sensitive amplification scheme (PSA) and the phase insensitive amplification scheme (PIA). For the PIA case, we show the degradation of the signal to noise ratio. And for the PSA case, we achieved the first spatially noiseless amplification of images. For both cases, experimental values are in good agreement with theoretical noise figure. Moreover, we study the spatial fluctuations of parametric fluorescence. Using short pulses combined with a narrow spectral filter, we directly characterize a pure distribution of Bose-Einstein; Ce mémoire présente une étude expérimentale des fluctuations spatiales d'origine quantique de l'intensité dans des images en amplification paramétrique optique (OPA). Dans un premier temps nous avons caractérisé la réponse d'une caméra CCD lors de la mesure du bruit de photons dans le plan transverse de l'image. Pour cela, nous avons montré la pleine aptitude des capteurs silicium pour le domaine visible (527 nm) et leur mauvaise réponse dans le proche IR (1055 nm). Puis nous avons calibré le capteur sur toute sa dynamique afin d'éliminer l'inhomogénéité de réponse des pixels et ainsi mesurer le bruit de photons dans des images faibles ou intenses. D'autre part, nous avons étudié les aspects quantiques des OPA. L'amplification à l'aide d'un cristal de BBO de type I d'images (527 nm) dominées par le bruit quantique à l'aide d'une pompe UV (264nm) s'est imposée comme le meilleur compromis expérimental. Nous avons mis au point un montage et un protocole de mesure permettant la comparaison entre l'amplification sensible à la phase (PSA) et l'amplification insensible à la phase (PIA). Dans le cas d'une PIA, nous avons mis en évidence la dégradation du rapport signal à bruit. Pour la configuration PSA, nous avons réalisé la première amplification paramétrique d'images sans bruit spatial. Pour ces deux cas, les valeurs expérimentales sont en accord avec la figure de bruit attendue. De plus, nous avons étudié la distribution des fluctuations spatiales de la fluorescence paramétrique. L'emploi d'impulsions brèves et un fort filtrage des longueurs d'onde ont permis la caractérisation directe de la distribution de Bose-Einstein pure.