Application of a simplified thermal-electric model of a sodium-nickel chloride battery energy storage system to a real case residential prosumer

Recently, power system customers have changed the way they interact with public networks, playing a more and more active role. End-users first installed local small-size generating units, and now they are being equipped with storage devices to increase the self-consumption rate. By suitably managing local resources, the provision of ancillary services and aggregations among several end-users are expected evolutions in the near future. In the upcoming market of household-sized storage devices, sodium-nickel chloride technology seems to be an interesting alternative to lead-acid and lithium-ion batteries. To accurately investigate the operation of the NaNiCl2 battery system at the residential level, a suitable thermoelectric model has been developed by the authors, starting from the results of laboratory tests. The behavior of the battery internal temperature has been characterized. Then, the designed model has been used to evaluate the economic profitability in installing a storage system in the case that end-users are already equipped with a photovoltaic unit. To obtain realistic results, real field measurements of customer consumption and solar radiation have been considered. A concrete interest in adopting the sodium-nickel chloride technology at the residential level is confirmed, taking into account the achievable benefits in terms of economic income, back-up supply, and increased indifference to the evolution of the electricity market

Psychopathology, dissociation and somatic symptoms in adolescents who were exposed to traumatic experiences

Background: The direct and long-term effects of children's exposure to traumatic events can be seen in a complex continuum, based first of all on the type of trauma. Children's reactions to trauma may have different manifestations from the clinical picture of the PTSD, exhibiting dissociative, somatic, depressive or anxiety symptoms, and/or disruptiveness. Aim: we conducted a cross-sectional study in a psychiatric patients sample to determine the extent to which complex trauma history is associated with disease-related characteristics (diagnosis, dissociative symptoms, somatic symptomatology, impairment degree). Methods: We have enrolled 107 subjects, aged between 12 and 18 years, who consecutively referred for a psychiatric evaluation to the Child Neuropsychiatry Unit of the Del Ponte Hospital in Varese. All subjects underwent a clinical evaluation performed by infantile neuropsychiatrists. The battery of tests that was administered to patients included CGI and CGAS (filled out by the clinician), CBCL (filled out by parents), MMPI-A and TSSC-A (filled out by patients), and Wechsler scale. Results: We found out that 35.5% of subjects had a mood disorder, 23.4% a personality disorder, 13.1% a psychotic disorder, 20.6% a post-traumatic stress disorder, while 26.2% were classified as other diagnostic categories (more frequently ADHD, DOP and conduct disorders). 58.9% of patients had at least one comorbidity. 33.6% of subjects also experienced a complex trauma. In multivariate logistic regression analyses, subgroup fellows were collapsed to compare the single trauma and no trauma versus complex trauma group. Gender, age and affective disorders were generally unrelated to subjects', clinicians', and parents' scores. About subjects' self-assessment (MMPI-A Structural Summary Factors), complex trauma history was a statistically significant contributor to high scores on the Immaturity, Health Concerns, Familial Alienation and Psychoticism Factors, followed by presence of dissociative symptoms (except for Familial Alienation factor). Presence of dissociative symptoms, personality and psychotic disorder diagnosis was related to higher clinician impairment scores (CGI-S > 4). Conclusion: These results reinforce available evidence that in trauma-exposed adolescents, the full burden of trauma, including other psychiatric diagnosis than PTSD (such as affective, personality, and psychotic disorders), dissociative and somatic symptomatology, is substantial and needs appropriate assessment and therapeutic interventions

Sodium nickel chloride battery steady-state regime model for stationary electrical energy storage

The purpose of this paper is presenting a reliable modelling of sodium-chloride battery in order to have a powerful tool which is able to foresee the steady state battery behaviour in both discharge and charge operations. The proposed modelling approach allows representing both constant current operations and variable charge/discharge current ones. The model can be classified as an experimental one because it is based on a wide set of measures. All the main modelling steps are described and a comparison between the model results and real battery measures, with the same conditions, is presented. The very good agreement between measures and model confirms the robustness of the approach for steady state applications. The model was tested for fast transient operations also, by alternatively opening and closing the battery circuit during discharge/charge operations. In these conditions, the model is not able to perfectly follow the actual voltage behaviour, even if the battery voltage error is small. Therefore, the limit of this model is that it cannot represent the actual transient behaviour of the battery voltage. The paper proposes to adopt a set of standard battery measures from which it is possible to infer a simple but very precise modelling structure, in order to represent the steady state behaviour of NaNiCl2 batteries

Sodium nickel chloride battery technology for large-scale stationary storage in the high voltage network

The extensive application of Sodium-Nickel Chloride (Na-NiCl2) secondary batteries in electric and hybrid vehicles, in which the safety requirements are more restrictive than these of stationary storage applications, depicts the Na-NiCl2 technology as perfectly suitable for the stationary storage applications. The risk of fire is negligible because of the intrinsic safety of the cell chemical reactions, related to the sodium-tetrachloroaluminate (NaAlCl4) content into the cell, which acts as a secondary electrolyte (the primary one being the ceramic \u3b2''-alumina as common for Na-Beta batteries). The three hour rate discharge time makes this technology very attractive for load levelling, voltage regulation, time shifting and the power fluctuation mitigation of the renewable energy sources in both HV and EHV networks

Test di sicurezza su batterie sodio-cloruro di nichel per l\u2019accumulo elettrochimico stazionario

Le installazioni su larga scala di accumulo elettrochimico nel territorio nazionale [1-5], a cui questa rivista ha dato largo spazio [1-3], rappresentano degli utilissimi banchi di prova per verificarne l'efficacia e i rendimenti sia negli utilizzi per cariche/scariche di lunga durata (Energy intensive) sia in quelli di durate brevi (Power intensive). Le installazioni Energy intensive realizzate da Terna Storage ammontano a 34,8 MW [1]. Si \ue8 pi\uf9 volte sottolineato [1, 2] come le problematiche di sicurezza giochino un ruolo chiave per l'ottenimento "rapido" delle autorizzazioni e per l'accettabilit\ue0 sociale di siffatte tecnologie. Conseguentemente, FIAMM SONICK ha sottoposto la propria tecnologia a test molto severi per validarne la sicurezza sia in caso di esercizio normale sia in caso dei pi\uf9 disparati eventi incidentali. Per quanto riguarda il funzionamento di questa cella si rimanda alla bibliografia [2, 4] e soprattutto alla memoria pubblicata in questa stessa rivista [2]. Di seguito vengono quindi descritti i test effettuati sia sulle celle sia sui vari modelli di moduli sia sull'unit\ue0 (assemblato di moduli). Si noti che, data l'applicazione prevalente di siffatta tecnologia all'ambito automobilistico, le caratteristiche di tenuta agli urti, l'assenza di innesco d'incendio endogeno e la tenuta a quello esogeno sono caratteristiche precipue e ineludibili (corroborate dai vari test di cui si dar\ue0 un resoconto). Nelle applicazioni stazionarie, le caratteristiche suddette danno ampie garanzie nell'analisi del rischio che le magnitudo per i vari scenari incidentali (inondazioni, incendio esogeno e endogeno, urti e cadute dei moduli) siano estremamente contenute. Nel prosieguo verranno dati alcuni dettagli su alcuni test effettuati

Defective tumor necrosis factor-alpha-dependent control of astrocyte glutamate release in a transgenic mouse model of Alzheimer disease.

The cytokine tumor necrosis factor-alpha (TNFalpha) induces Ca2+-dependent glutamate release from astrocytes via the downstream action of prostaglandin (PG) E2. By this process, astrocytes may participate in intercellular communication and neuromodulation. Acute inflammation in vitro, induced by adding reactive microglia to astrocyte cultures, enhances TNFalpha production and amplifies glutamate release, switching the pathway into a neurodamaging cascade (Bezzi, P., Domercq, M., Brambilla, L., Galli, R., Schols, D., De Clercq, E., Vescovi, A., Bagetta, G., Kollias, G., Meldolesi, J., and Volterra, A. (2001) Nat. Neurosci. 4, 702-710). Because glial inflammation is a component of Alzheimer disease (AD) and TNFalpha is overexpressed in AD brains, we investigated possible alterations of the cytokine-dependent pathway in PDAPP mice, a transgenic model of AD. Glutamate release was measured in acute hippocampal and cerebellar slices from mice at early (4-month-old) and late (12-month-old) disease stages in comparison with age-matched controls. Surprisingly, TNFalpha-evoked glutamate release, normal in 4-month-old PDAPP mice, was dramatically reduced in the hippocampus of 12-month-old animals. This defect correlated with the presence of numerous beta-amyloid deposits and hypertrophic astrocytes. In contrast, release was normal in cerebellum, a region devoid of beta-amyloid deposition and astrocytosis. The Ca2+-dependent process by which TNFalpha evokes glutamate release in acute slices is distinct from synaptic release and displays properties identical to those observed in cultured astrocytes, notably PG dependence. However, prostaglandin E2 induced normal glutamate release responses in 12-month-old PDAPP mice, suggesting that the pathology-associated defect involves the TNFalpha-dependent control of secretion rather than the secretory process itself. Reduced expression of DENN/MADD, a mediator of TNFalpha-PG coupling, might account for the defect. Alteration of this neuromodulatory astrocytic pathway is described here for the first time in relation to Alzheimer disease