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The integration of an increasing share of Renewable Energy Sources (RES) requires the availability of suitable energy storage systems to improve the grid flexibility and Compressed Air Energy Storage (CAES) systems could be a promising option. In this study, a CO2-free Diabatic CAES system is proposed and analyzed. The plant configuration is derived from a down-scaled version of the McIntosh Diabatic CAES plant, where the natural gas is replaced with green hydrogen, produced on site by a Proton Exchange Membrane electrolyzer powered by a photovoltaic power plant. In this study, the components of the hydrogen production system are sized to maximize the self-consumption share of PV energy generation and the effect of the design parameters on the H2-CAES plant performance are analyzed on a yearly basis. Moreover, a comparison between the use of natural gas and hydrogen in terms of energy consumption and CO2 emissions is discussed. The results show that the proposed hydrogen fueled CAES can effectively match the generation profile and the yearly production of the natural gas fueled plant by using all the PV energy production, while producing zero CO2 emissions. [ABSTRACT FROM AUTHOR]

The capability of shifting the electricity generation or consumption to proper time of the day, also defined as energy shift (ES), is the key factor to ensure the power balance, especially under high penetration of variable renewable energy (VRE). However, the ES is not characterized and traded as an independent product in current market mechanisms. In this letter, the marginal utility of an ES is assessed and leveraged to characterize the effective ES, while a novel market scheme is proposed considering the trading of both ES and energy level (EL). The proposed scheme can well integrate ES producers such as virtual power plants that cannot be rewarded sufficiently to actively participate in the current market because they are principally labeled as EL consumers. Finally, the novel concept and mechanism are illustrated by a numerical study and verified to outperform the existing price schemes on integrating the ES resources and VRE.

In the literature, there were studies of Rydberg states of hydrogenic atoms/ions in a high-frequency laser field. It was shown that the motion of the Rydberg electron is analogous to the motion of a satellite around an oblate planet (for a linearly polarized laser field) or around a (fictitious) prolate planet (for a circularly polarized laser field): it exhibits two kinds of precession – one of them is the precession within the orbital plane and another one is the precession of the orbital plane. In this study, we study a helium atom or a helium-like ion with one of the two electrons in a Rydberg state, the system being under a high-frequency laser field. For obtaining analytical results, we use the generalized method of the effective potentials. We find two primary effects of the high-frequency laser field on circular Rydberg states. The first effect is the precession of the orbital plane of the Rydberg electron. We calculate analytically the precession frequency and show that it differs from the case of a hydrogenic atom/ion. In the radiation spectrum, this precession would manifest as satellites separated from the spectral line at the Kepler frequency by multiples of the precession frequency. The second effect is a shift of the energy of the Rydberg electron, also calculated analytically. We find that the absolute value of the shift increases monotonically as the unperturbed binding energy of the Rydberg electron increases. We also find that the shift has a nonmonotonic dependence on the nuclear charge Z: as Z increases, the absolute value of the shift first increases, then reaches a maximum, and then decreases. The nonmonotonic dependence of the laser field-caused energy shift on the nuclear charge is a counterintuitive result.

This theory-building research intends to dig into the renewable energy industry and drawing from research on learning curves and energy polices, proposes a way to speed-up the energy shift from our fossil-fuel dependency to a green economy. Even though standard economic frameworks suggest that markets and not policy makers should decide winners and losers, we urge to accelerate renewable energy competitiveness, proposing that by limiting the number of maturing renewable technologies where resources are allocated to at government level, we reduce the time within which renewables will achieve technological price parity with fossil fuels. In turn, by analyzing the energy demand and supply curves, the study suggests that this action will also mediate the relation between quantity and price, shifting only the supply curve, leaving the demand curve unaffected. It continues by proposing the standardization of a unique renewable energy supply chain model, defined as the SURESC model, relating the indirect effect of limiting the number of maturing technologies to allocate resources, to achieve renewable price-parity with conventional energy sources faster. This is a preliminary theoretical study intended to provide a holistic approach to a known problem.

This theory-building research intends to dig into the renewable energy industry and drawing from research on learning curves and energy polices, proposes a way to speed-up the energy shift from our fossil-fuel dependency to a green economy. Even though standard economic frameworks suggest that markets and not policy makers should decide winners and losers, we urge to accelerate renewable energy competitiveness, proposing that by limiting the number of maturing renewable technologies where resources are allocated to at government level, we reduce the time within which renewables will achieve technological price parity with fossil fuels. In turn, by analyzing the energy demand and supply curves, the study suggests that this action will also mediate the relation between quantity and price, shifting only the supply curve, leaving the demand curve unaffected. It continues by proposing the standardization of a unique renewable energy supply chain model, defined as the SURESC model, relating the indirect effect of limiting the number of maturing technologies to allocate resources, to achieve renewable price-parity with conventional energy sources faster. This is a preliminary theoretical study intended to provide a holistic approach to a known problem.

This study intends to dig into the renewable energy industry and drawing from research on learning curves and energy polices, proposes a way to speed-up the energy shift from our fossil-fuel dependency to a green economy. Even though standard economic frameworks suggest that markets and not policy makers should decide winners and losers, we urge to accelerate renewable energy competitiveness, proposing that by limiting the number of renewable technologies where resources are allocated to at government level, we reduce the time within which renewables will achieve technological price parity with fossil fuels. In turn, by analyzing the energy demand and supply curves, the study suggests that this action will also mediate the relation between quantity and price, shifting only the supply curve, leaving the demand curve unaffected. It continues by proposing the standardization of a unique renewable energy supply chain model, later defined as the SURESC model. For such, a deep analysis on existing green technologies will be performed proposing the implementation of a hydrogen through ammonia economy via ammonia for power as key factor for success. This is a preliminary study, first of its kind, intended to provide a holistic approach to a known problem.

This study intends to dig into the renewable energy industry and drawing from research on learning curves and energy polices, proposes a way to speed-up the energy shift from our fossil-fuel dependency to a green economy. Even though standard economic frameworks suggest that markets and not policy makers should decide winners and losers, we urge to accelerate renewable energy competitiveness, proposing that by limiting the number of renewable technologies where resources are allocated to at government level, we reduce the time within which renewables will achieve technological price parity with fossil fuels. In turn, by analyzing the energy demand and supply curves, the study suggests that this action will also mediate the relation between quantity and price, shifting only the supply curve, leaving the demand curve unaffected. It continues by proposing the standardization of a unique renewable energy supply chain model, later defined as the SURESC model. For such, a deep analysis on existing green technologies will be performed proposing the implementation of a hydrogen through ammonia economy via ammonia for power as key factor for success. This is a preliminary study, first of its kind, intended to provide a holistic approach to a known problem.

In paper, using exact solutions of the stationary Schrödinger equation and the equation of motion for an elastic semiconductor medium, using the secondary quantization formalism, the theory of interaction of electrons with acoustic phonons in a multilayer arsenide-based AlAs/GaAlAs resonant tunneling structure is developed. Using the Matsubara Green's functions and the Dyson equation, expressions, which describe the temperature energy shifts of electronic levels in the nanostructure and their decay rates, are established. Direct calculations of the quantities characterizing the interaction of electrons with acoustic phonons are performed on the basis of physical and geometric parameters of a typical nanostructure, and their dependences on the geometric design of the total potential well of the nanosystem at various temperatures are studied. It is shown that the influence of acoustic phonons leads to the decrease in the quantum electronic transitions frequency in the studied nanostructure, and this effect becomes more noticeable with increasing temperature. It has been established that the absolute values of the electronic stationary states temperature shifts decreases with the increase in the electronic stationary level number. Also, an increase in the temperature entails an increase in the electronic states decay rates that is a dissipation effect directly affecting electronic processes in nanostructures. [ABSTRACT FROM AUTHOR]

We experimentally studied the Rydberg level shift caused by the electric field, which is generated by Rydberg atom collision induced ionization in a cesium atomic ensemble. The density of charged particles caused by collisions between Rydberg atoms is changed by controlling the ground-state atomic density and optical excitation process. We measured the Rydberg level shift using Rydberg electromagnetically-induced-transparency (EIT) spectroscopy, and interpreted the physical origin using a semi-classical model. The experimental results are in good agreement with the numerical simulation. These energy shifts are important for the self-calibrated sensing of microwave field by the employing of Rydberg EIT. Moreover, in contrast to the resonant excitation case, narrow-linewidth spectroscopy with high signal-to-noise ratio would be useful for high-precision measurements. [ABSTRACT FROM AUTHOR]

We experimentally studied the Rydberg level shift caused by the electric field, which is generated by Rydberg atom collision induced ionization in a cesium atomic ensemble. The density of charged particles caused by collisions between Rydberg atoms is changed by controlling the ground-state atomic density and optical excitation process. We measured the Rydberg level shift using Rydberg electromagnetically-induced-transparency (EIT) spectroscopy, and interpreted the physical origin using a semi-classical model. The experimental results are in good agreement with the numerical simulation. These energy shifts are important for the self-calibrated sensing of microwave field by the employing of Rydberg EIT. Moreover, in contrast to the resonant excitation case, narrow-linewidth spectroscopy with high signal-to-noise ratio would be useful for high-precision measurements.

Worldwide environmental policies demand each time more biofuel consumption and less emission. In this context, this work presents a 2G ethanol study as a mean to increase bioethanol production and availability. Currently, technologies use sugarcane bagasse for lignocellulosic ethanol production, which may unbalance the ethanol and sugar mill energy matrix, since bagasse and straw are the main fuel for power and steam generation. A possible solution is using biogas produced from vinasse biodigestion as a fuel instead of using biomass, enabling to shift a fraction of the sugarcane bagasse to 2G ethanol production and, at the same time, keeping power and steam production constant. This paper assesses that energy shift by analyzing ten different scenarios for power generation, comparing the amount of bagasse shifted, the increase in straw consumption, the increase in ethanol production and the reduction of environmental emissions in each scenario. The results show that, at least from the technical and environmental perspective, a combined cycle operating at a high pressure is the best alternative. It is possible to shift from 56.5% to 100% of the available bagasse using the combined cycle technology, which is also followed by an increase in straw consumption. In addition to that, the ethanol availability increase ranges from 28.5 to 50.4%. Moreover, the organic load disposal to the ground also decreases more than 90% compared to the conventional process due to the introduction of vinasse biodigestion. [ABSTRACT FROM AUTHOR]

The atomic intermixing of InxGa1-xAs/InP quantum well structures induced by arsenic irradiation has been investigated using photoluminescence (PL) measurement. The ion doses used were varried from 5x1011 As/cm2 to 1x1013 As/cm2. Also, the irradiation temperature were carried out from -200oC to 300oC. The samples were annealed under Argon flow in rapid thermal annealer (RTA) at 750oC for 60 second. The photoluminescence result showed that there was increase in energy shift at lower doses. However, the energy shift was saturated at higher dose. At elevated temperature implantation showed that the energy shift did not change significantly for all the samples (LM, TS, CS). In additon to this, the higher energy shift was observed in the Compressive Strain (CS) samples, but the lower of the energy shift was experienced in the Tensile Strain (TS) samples

The dispersion law and the anomalous magnetic moment of a neutrino in a magnetized electron-positron plasma are investigated as functions of the magnetic field strength, the polarization state, energy, direction of motion, and mass of the neutrino, and the parameters of the plasma. The calculation was performed by the method of the time Green's functions at finite temperature. Results for a massive neutrino in the limiting case are compared with the results of other authors, obtained earlier for a massless left-handed neutrino. [ABSTRACT FROM AUTHOR]

In neutron imaging, the beam-hardening effect has a significant effect on quantitative and qualitative image interpretation. This study aims to propose a linearization method for beam-hardening correction. The proposed method is based on a new analytical approach establishing the attenuation coefficient as a function of neutron energy. Spectrum energy shift due to beam hardening is studied on the basis of Monte Carlo N-Particle (MCNP) simulated data and the analytical data. Good agreement between MCNP and analytical values has been found. Indeed, the beam-hardening effect is well supported in the proposed method. A correction procedure is developed to correct the errors of beam-hardening effect in neutron transmission, and therefore for projection data correction. The effectiveness of this procedure is determined by its application in correcting reconstructed images. [ABSTRACT FROM AUTHOR]

The research presented in this paper is structured on the basis of the extensive literature on the world energy shift and, in particular, the dynamics of the political, social, market, and community acceptability of different energy sources. This study attempts to determine which sources of energy are most accepted or preferred by political systems, public opinion, and the market and the weights that these dynamics of acceptability have on the global energy shift. In this theoretical framework, we present an application and propose a methodology resulting from the integration of two methods: the Delphi method and the analytic hierarchy process (AHP). While Delphi seeks a convergence of opinions among a group of experts, the AHP helps solve complex decision problems using a hierarchical structure. To integrate the Delphi and AHP methods, we propose an innovation in the way the feedbacks are circulated among the participants. The experts' judgements are given in a box-plot using a slider, which simplifies the procedure because the respondents have all the most important information on the distribution of responses from the previous round. At the same time, our method eliminates the problem of the choice of one of the diverse methods of aggregation, which are necessary when the AHP is applied in a group setting. The application of this method to energy issues and the dynamics of the acceptability of the different sources in particular revealed the feasibility and advantages of the instrument and produced interesting results. [ABSTRACT FROM AUTHOR]

Simultaneous effects of spin-spin and spin-orbit interactions on the energy spectrum of a two-electron spherical quantum dot with parabolic confinement and under the influence of external electric and magnetic fields are investigated. We have calculated energy eigenvalues and eigenvectors of the system for different spin states. Results show that effects of spin-spin interactions are negligible in comparison with those of the spin-orbit interactions. Spin-orbit interaction splits energy levels and removes degeneracy of different spin states. Moreover it is seen that energy eigenvalues and levels splitting strongly depend on the external magnetic field and the dot dimensions. [ABSTRACT FROM AUTHOR]

Uranium L X-ray absorption edge was measured in various compounds containing uranium in U, U and U oxidation states. The measurements have been carried out at the Energy Dispersive EXAFS beamline (BL-08) at INDUS-2 synchrotron radiation source at RRCAT, Indore. Energy shifts of ~ 2-3 eV were observed for U L edge in the U-compounds compared to their value in elemental U. The different chemical shifts observed for the compounds having the same oxidation state of the cation but different anions or ligands show the effect of different chemical environments surrounding the cations in determining their X-ray absorption edges in the above compounds. The above chemical effect has been quantitatively described by determining the effective charges on U cation in the above compounds. [ABSTRACT FROM AUTHOR]