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The increase in the number of installed renewable energy in a residential network needs an efficient energy management system (EMS) to store or sell the surplus energy back to the grid during the surplus generation. Selling of power back to the grid can affect the reliability of the traditional grid system, to avoid this energy sharing is proposed to share the surplus energy with close neighbours to avoid the transmission loss and increase the utilization rate of renewable energy. In this paper, we use the cyber-physical system (CPS) to coordinate the neighbours and to collect data from all the homes using the smart meters. The system’s objective is to reduce the grid cost and to benefit each home which shares the energy. This system reduces the need for a huge energy storage system (ESS) which is a major capital cost during the installation. We adopt a scheduling algorithm to manage the loads during the shortage of supply and flexibility in scheduling the loads helps to improve energy management without disturbing the user comfort. The whole model is validated with an experimental setup in the university as a part of the MNRE Funded Project.

With the large-scale integration of clean energy resources, microgrids have shifted from consumer to prosumer. Therefore, the behavior of microgrids would have an enormous impact on the distribution network and electricity market. In this context, this paper established an optimal energy sharing model for multi-microgrids under the condition of the constructing cooperative alliance relationship. An overall operation strategy to maximize clean energy utilization and overall benefits is constructed by a two-stage robust model considering the uncertainty of clean energy. Also, a Shapley model is established to distribute the profit based on the contribution among multi-microgrids. Finally, a test case is applied to demonstrate the effectiveness of the proposed model and is given to verify that the economic benefits of each microgrid are improved after optimization.

Growth in the adoption of distributed energy resources is shaping a new energy ecosystem posing a perceptible threat to the grid by relying on it as a virtually inexpensive storage mechanism. This growth is compounded by new policy objectives that require pursuing net zero energy (NZE) goals for new buildings. One emerging framework that attempts to remediate this problem is energy sharing in a community microgrid. In this framework, through complementary demand profiles and shared energy storage, buildings use energy resources more efficiently with the objective of reducing grid interactions. In this paper, we create a year-long discrete-time simulation model of 40 residential and non-residential buildings to measure the reduction in grid interactions through energy sharing and shared storage for the case of a NZE community. Our results show that, when sharing is enabled, a 9.5% reduction in grid interactions can be obtained with buildings that have energy storage. Additionally, a month-by-month exploration revealed that annual patterns in generation drastically impact the benefits from sharing energy. The reduction in grid utilization ranged from 20% during periods of high energy surplus (i.e. summer) to 5% during low energy generation (i.e. winter).

Complete two-photon break-up of He near threshold has been investigated by solving the time-dependent closing-coupling equations on a numerical lattice. We have obtained good agreement for the total double ionization cross-section with previous theoretical results. The triple-differential cross-sections exhibit interesting features as the two-photon energy approaches the threshold of double ionization. We found that two-electron ejection with equal energy sharing is most probable near the two-photon threshold, in contrast to the case away from threshold, where ejection with large unequal energy sharings is most probable.

We present in this communication the results of our calculation of triple differential cross section (TDCS) and spin asymmetry in TDCS in (e, 2e) processes on Li, Be+, B+2 and C+3 targets at an incident electron energy 49 eV above the ionization potential for equal as well as unequal energy sharing conditions. We have performed the calculation in distorted wave Born approximation (DWBA) formalism using static exchange potential. We also present our calculation of spin asymmetry for Li like targets as a function of energy sharing ratio and compare it with the available experimental data for Li atom. We discuss the role of exchange effect in producing spin asymmetry. We observe that the triplet scattering process plays an important role as the nuclear charge is increased. Further we observe that the spin asymmetry variation with the energy sharing ratio is also sensitive to the nuclear charge.

New coplanar (e, 3-1e) experiments on double ionization (DI) of helium and molecular hydrogen at about 600 eV incident energy, and with asymmetric energy sharing among the two ejected electrons are presented. The results are compared with state-of-the-art first-order theories, and are discussed in terms of DI mechanisms. Evidence is given of the great importance of second- or higher-order effects in the projectile-target interaction, even at the high incident energy considered.

Several model functions capable of representing the symmetrized transition amplitudes within the parametrization formalism of Huetz et al for the photodouble ionization of helium are proposed. The model is based on the well documented features of the gerade transition amplitude in the cases of symmetric energy sharing and/or small excess energies. Those are extended towards the higher excess energies and for an arbitrary energy sharing, where both the gerade and the ungerade components of the transition matrix contribute, with a minimum of modifications. Excellent agreement between a sample of experimental and theoretical triple differential cross sections (TDCS) extending up to 40 eV on one side and the parametric form on the other is obtained by using just three adjustable parameters which could be reliably extracted from most experiments. This creates the possibility for a complete dynamical parametrization of the TDCS in the low to intermediate excess energy range.

The triple differential cross section (TDCS) for double photoionization of calcium atoms has been studied, in the region of the Ca 3p3d giant resonance, for equal and unequal energy sharing by the two electrons. The measurements were performed at two different photon energies corresponding to different resonance symmetries, and the results show that the TDCS is strongly resonance dependent. For a fixed total energy the TDCS, at a relative angle of 180° for the two electrons, has been found to increase approximately linearly with increasing energy of one of the electrons.

We have measured absolute triple differential cross sections for photo-double ionization of helium at 20 eV excess. The measurement covers the full ranges of energy sharing and emission angles of the two photoelectrons. We compare our data for selected geometries with the convergent close-coupling (CCC) calculations as well as 2SC calculations by Pont and Shakeshaft and 3C calculations by Maulbetsch and Briggs. In terms of the absolute magnitude and the trend in the shapes of the triple differential cross section for different geometries we find good agreement of the CCC and published 2SC calculations with our measurement, though differences with respect to the observed shape of individual patterns still exist.

Spin-resolved triple differential cross sections have been measured for ionization of xenon atoms by polarized electrons for energies between 40 and . Significant spin up-down asymmetries in the cross sections have been obtained at all energies. These are dominated by the interplay of orbital orientation, fine-structure interaction and exchange of the colliding electrons (`fine-structure effect'), whereas the influence of relativistic orbitals and of the continuum spin-orbit interaction is less important. The results are compared with recent DWBA calculations that include exchange with the electrons of the residual ion (exchange distortion), and satisfactory agreement is found. In particular, the discrepancies between theory and experiment at and symmetric energy sharing are resolved.

Triple differential cross sections (TDCS) for double photoionization in and (for comparison also in helium) have been measured for equal energy sharing, eV. In agreement with previous observations by the Reddish group and in comparison to the equivalent helium case, our data confirm a `narrowing' effect in the correlation factor which influences the observed TDCS lobes, as well as a `filling-in' effect at relative angles . However, we do not confirm the previous differences in the magnitude of and TDCS values. Instead, we get equal TDCS strengths and, in comparison to helium, reasonable agreement with the corresponding total cross section ratio for double photoionization in He and .

In this paper the triple differential cross sections for electron impact ionization of helium in the coplanar equal energy-sharing geometry is considered. A new collision process called triple-binary collision is identified in the situation where the angle of the two outgoing electrons is fixed. It has been shown how the dominant collision mechanisms change as the incident energy increases. It has also been shown how the exchange effects contribute to the cross sections.

We present a combined experimental and theoretical study of the electron-impact ionization of helium at 44.6 eV incident energy. The absolute coplanar triple differential cross sections (TDCS) are measured in different geometrical arrangements, with the excess energy being equally shared between the two outgoing electrons. The measurements are compared with the convergent close-coupling (CCC) theory. The measured angular distributions of the TDCS are well reproduced by the calculations. Good agreement in magnitude is also obtained after the CCC results have been multiplied by a single factor derived from the comparison of the CCC and estimated true single differential cross sections. This suggests that the CCC theory yields accurate angular and, after rescaling, absolute distributions for all in- and out-of-plane geometries.

Electron-impact ionization of the ground state of helium is measured and calculated for the case of 64.6 eV incident electrons with coplanar outgoing 20 eV electrons. Various geometries are considered: symmetric, fixed and fixed . The method of calculation is the convergent close-coupling theory. This theory is able to reproduce the angular profiles in essentially all of these geometries, yet it yields cross sections which are a constant factor of approximately two lower than experiment.

We present a combined experimental and theoretical study of ionization of the ground state of helium by 40 eV incident electrons. Absolute in-plane and out-of-plane measurements are provided for the case of 4 eV slow electron energy. These are found to be in good agreement with the convergent close-coupling (CCC) calculations. Three calculations are presented, in order to demonstrate convergence, which couple a total of 87, 99 and 103 states. These also simultaneously yield results for the equal energy sharing kinematics which are found to be in good agreement with the available relative coplanar symmetric measurements.

Calculations using the distorted-wave first Born model are reported for the triple differential cross section for electron-impact ionization of atomic hydrogen at low energy. They are carried out in the coplanar asymmetric geometry for various deflection angles. Different kinematics are considered: unequal energy sharing between the outgoing electrons at 54.4 eV and equal energy sharing at 27.2, 17.6 and 15.6 eV. We attempt to improve the theoretical description of the initial state and propose four models, three of which include a polarization of the target orbital. The associated polarization potential is used in addition to the static and the static-exchange potentials to calculate the distorted wave. We account for electron-pair correlation in the final state by use of a Gamow correction factor.

We report the results of fully relativistic distorted-wave calculations for (e,2e) collisions at high energies on gold and uranium targets in a coplanar symmetric geometry. The results for gold are in excellent agreement with available absolute experimental data. We also observe a peak in the triple differential cross section at large angles which may be interpreted in terms of a multiple scattering mechanism. In the present case of large impact energies, the ratio of the large angle to the binary peak is several orders of magnitude larger than that previously observed at non-relativistic energies. Our calculations indicate that this peak should be accessible to experiment. We propose a new geometrical arrangement for experiments which we believe offers distinct advantages in the study of distortion effects in relativistic (e,2e) processes.

The triply differential cross section (TDCS) for double photoionization of helium is calculated using a three-body Coulomb correlated final state wavefunction which treats the three Coulomb particles on an equal basis. Complementary to preceding publications by Maulbetsch and Briggs (1992, 1993) emphasis is given to the case of unequal sharing of the available excess energy. The breakdown of selection rules which apply in the equal energy sharing case leads to a greater variety of angular patterns. Excellent agreement is obtained with the first experimental results for unequal energy sharing.

Interest in (e-2e) processes in symmetric energy-sharing geometries has been stimulated by the new experimental work of Frost et al. (1989) and the theoretical calculations of Zhang et al. (1989), and also by the method developed by Gelebart et al. (1989) for obtaining absolute cross section values. Both Frost et al. and Zhang et al. find a deep minimum in the 200 eV cross section at an angle near to theta =85' which was not observed in earlier work by Pochat et al. (1983). The authors report absolute cross section measurements at 100 eV incident energy, over an angular range 35' to 150'. They also find a deep minimum at 85' and obtain generally good agreement with the calculations of Zhang et al. except that the cross sections tend to be larger than theirs in the region of the secondary maximum at around theta =110'.

The triple differential cross section for the electron impact ionization of Xe has been measured in an energy sharing coplanar symmetric arrangement for an incident energy of 200 eV. Comparison is made with experimental work on He at the same energy and with theoretical results calculated in the distorted-wave Born approximation. The enhancement of the large angle secondary peak predicted by Whelan and Walters (1989) is confirmed.

We have measured triple differential cross sections (TDCSs) for electron-impact ionization of the 3p shell of Ar at 200 eV incident electron energy. The experiments have been performed in coplanar asymmetric energy sharing geometry. The experimental results are compared with the theoretical models of three body distorted wave (3DW) and distorted wave Born approximation (DWBA).

Energy sharing is considered for collision cascades in a polyatomic medium with constituents of very different atomic numbers and masses. Considerable disagreement is found between predictions of Anderson and Sigmund (1974) and a Monte Carlo simulation on HfC, even for equivalent physical input. An improved theory due to Urbassek and Conrad (1992) is shown to remove this discrepancy.

The triple differential cross section for electron impact ionisation of He is measured in 'energy-sharing' and 'non-coplanar symmetric' kinematics. Experiments performed at 424.5 eV incident energy and at different scattering angles are reported. The present experimental results are compared with the eikonal distorted-wave impulse approximation. They give further evidence for the inadequacy of this approximation at small scattering angles.