Simulation and operational modes of a plug and play storage for photovoltaic power

Renewable energy has become an important topic of today’s world. Renewable energy resources are inexhaustible, clean and they can be used in a decentralized way, i.e they can be generated and consumed directly in the same place, for example in domestic applications. In the last decades, the share of renewable energy in the energy mix has increased considerably, mainly because of the strict legislations and policies involving climate and energy goals and targets, but also without question, the increased self awareness and public perception regarding climate change and energy savings, in the citizens and as well in businesses or industries, therefore supporting the transition to a decarbonized energy system. However, since renewable energy often relies on weather conditions for the generation of power (e.g. in photovoltaic (PV) systems during the nighttime or during cloudy days where there is none or little energy production), problems such as unpredictability and unreliability emerge. Therefore, energy storage systems play an important role in creating a flexible and reliable system. In this work, a model of a complete domestic PV-battery system is modeled and simulated, whose goal is to develop a realistic model of a Plug & Play Storage of Photovoltaic Power (P 3P), a product that is currently being made by a start-up company in Graz. Said model firstly includes a PV module modeled in Simulink which also includes an irradiance model that relies in real measured data. Secondly, a battery model has been implemented in Matlab by means of power and energy balances, with one control strategy which also includes four different operational modes and additionally aging effects have been implemented. Thirdly, based on real data and by means of curve fitting, an inverter model has also been developed in Matlab. The special feature of the aforementioned system is that energy can be purchased from the grid but the surplus of generated energy cannot be fed into it. Finally, a sensitivity analysis was carried out to quantify and evaluate the influence of changing the predefined standard parameters over the whole system by comparing it to a performance parameter, enabling to find the best system configuration for the considered scenario.Outgoin

Cyclase-associated protein 1 (CAP1) promotes cofilin-induced actin dynamics in mammalian nonmuscle cells

Cyclase-associated proteins (CAPs) are highly conserved actin monomer binding proteins present in all eukaryotes. However, the mechanism by which CAPs contribute to actin dynamics has been elusive. In mammals, the situation is further complicated by the presence of two CAP isoforms whose differences have not been characterized. Here, we show that CAP1 is widely expressed in mouse nonmuscle cells, whereas CAP2 is the predominant isoform in developing striated muscles. In cultured NIH3T3 and 1316171 cells, CAP1 is a highly abundant protein that colocalizes with cofilin-1 to dynamic regions of the cortical actin cytoskeleton. Analysis of CAP1 knockdown cells demonstrated that this protein promotes rapid actin filament depolymerization and is important for cell morphology, migration, and endocytosis. Interestingly, depletion of CAP1 leads to an accumulation of cofilin-1 into abnormal cytoplasmic aggregates and to similar cytoskeletal defects to those seen in cofilin-1 knockdown cells, demonstrating that CAP1 is required for proper subcellular localization and function of ADF/cofilin. Together, these data provide the first direct in vivo evidence that CAP promotes rapid actin dynamics in conjunction with ADF/cofilin and is required for several central cellular processes in mammals

Estimation of inbreeding depression on female fertility in the Finnish Ayrshire population

Single nucleotide polymorphism (SNP) data enable the estimation of inbreeding at the genome level. In this study, we estimated inbreeding levels for 19,075 Finnish Ayrshire cows genotyped with a low-density SNP panel (8K). The genotypes were imputed to 50K density, and after quality control, 39,144 SNPs remained for the analysis. Inbreeding coefficients were estimated for each animal based on the percentage of homozygous SNPs (F-PH), runs of homozygosity (F-ROH) and pedigree (F-PED). Phenotypic records were available for 13,712 animals including non-return rate (NRR), number of inseminations (AIS) and interval from first to last insemination (IFL) for heifers and up to three parities for cows, as well as interval from calving to first insemination (ICF) for cows. Average F-PED was 0.02, F-ROH 0.06 and F-PH 0.63. A correlation of 0.71 was found between F-PED and F-ROH, 0.66 between F-PED and F-PH and 0.94 between F-ROH and F-PH. Pedigree-based inbreeding coefficients did not show inbreeding depression in any of the traits. However, when F-ROH or F-PH was used as a covariate, significant inbreeding depression was observed; a 10% increase in F-ROH was associated with 5days longer IFL0 and IFL1, 2weeks longer IFL3 and 3days longer ICF2 compared to non-inbred cows.Peer reviewe

Characterization of TiAlSiN/TiAlSiON/SiO2 optical stack designed by modelling calculations for solar selective applications

Preparation and characterization of TiAlSiN/TiAlSiON/SiO2 solar selective absorber is reported in this contribution. All layers were deposited in a continuous mode using a industrial equipment, the nitride and oxynitride were prepared by reactive magnetron sputtering and the SiO2 layer by Plasma Enhanced Chemical Vapour Deposition. The optical constants of individual layers were calculated by modelling of spectral transmittance and reflectance of the individual layers. The three layer stack absorber was then designed using those optical properties. The thickness of the individual layers was optimized until a solar absorptance of 96% was obtained resulting in a total thickness of about 200 nm, deposited in copper and extruded aluminium absorbers. An emissivity of 5 % for an absorber temperature of 100 ºC was obtained by analyzing the measuring data from a FTIR spectrometer with integrating sphere. After test duration of 600 h, the samples subjected to a thermal annealing at 278 ºC in air showed a performance criterion (PC) below 4% for, while the samples in the humidity tests showed a PC below 2 %.Savo Sola

Solar selective absorbers based on Al2O3:W cermets and AlSiN/AlSiON layers

Solar selective coatings based on double Al2O3:W cermet layers and AlSiN/AlSiON bilayer structures were prepared by magnetron sputtering. Both were deposited on stainless steel substrates using a metallic tungsten (W) layer as back reflector. The coating stacks were completed by an antireflection (AR) layer composed of Al2O3, SiO2, or AlSiOx. Spectrophotometer measurements, X-Ray diffraction, Scanning electron microscopy, Energy Dispersive X-Ray Spectroscopy and Rutherford Backscattering Spectrometry were used to characterize the optical properties, crystalline structure, morphology and composition of these coatings. The spectral optical constants of the single layers were calculated from the reflectance and transmittance measurements and used to design the optical stack. The coatings exhibit a solar absorptance of 93%-95% and an emissivity of 7%-10% (at 400 ºC). The coatings also exhibit excellent thermal stability, with small changes in the optical properties of the coating during heat-treatments at 400 ºC in air for 2500 h and at 580 ºC in vacuum for 850 h. The coating based on the AlSiN/AlSiON bilayer structure was obtained with an Al:Si ratio of 2.5:1. These coatings revealed similar performance as the one obtained with coatings based on Al2O3:W cermet layers.The authors acknowledge the funding from the Finnish Funding Agency for Technology and Innovation, Tekes, and from FEDER funds through the “Programa Operacional Factores de Competitividade – COMPETE” and from national funds by FCT- “Fundação para a Ciência e a Tecnologia”, under project no. PEst-C/FIS/UI0607/2011.info:eu-repo/semantics/publishedVersio

A design of selective solar absorber for high temperature applications

This study presents a design of multilayer solar selective absorber for high temperature applications. The optical stack of this absorber is composed of four layers deposited by magnetron sputtering on stainless steel substrates. The first is a back-reflector tungsten layer, which is followed by two absorption layers based on CrAlSiNx/ CrAlSiOyNx structure for phase interference. The final layer is an antireflection layer of SiAlOx. The design was theoretically modelled with SCOUT software using transmittance and reflectance curves of individual thin layers, which were deposited on glass substrates. The final design shows simultaneously high solar absorbance = 95.2 % and low emissivity ε= 9.8% (at 400 ºC) together with high thermal stability at 400 ºC, in air, and 600 ºC in vacuum for 650 h.The authors acknowledge the support of FCT in the framework of the Strategic Funding UID/FIS/04650/2013 and the financial support of FCT, POCI and PORL operational programs through the project POCI-01-0145- FEDER-016907 (PTDC/CTM-ENE/2882/2014), co-financed by European community fund FEDER.info:eu-repo/semantics/publishedVersio

Mechanical properties and microstructure of additively manufactured stainless steel with laser welded joints

Powder bed fusion (PBF) is a commonly employed metal additive manufacturing (AM) process in which components are built, layer-by-layer, using metallic powder. The component size is limited by the internal build volume of the employed PBF AM equipment; the fabrication of components larger than this volume therefore requires mechanical joining methods, such as laser welding. There are, however, very limited test data on the mechanical performance of PBF metal with laser welded joints. In this study, the mechanical properties of PBF built 316L stainless steel parts, joined together using laser welding to form larger components, have been investigated; the microstructure of the components has also been examined. 33 PBF 316L stainless steel tensile coupons, with central laser welds, welded using a range of welding parameters, and with coupon half parts built in two different orientations, were tested. The porosity, microhardness and microstructure of the welded coupons, along with the widths of the weld and heat-affected zone (HAZ), were characterised. The PBF base metal exhibited a typical cellular microstructure, while the weld consisted of equiaxed, columnar and cellular dendrite microstructures. Narrow weld regions and HAZs were observed. The PBF base metal was found to have higher proof and ultimate strengths, but a similar fracture strain and a lower Young’s modulus, compared with conventionally manufactured 316L stainless steel. The strengths were dependent on the build direction – the vertically built specimens showed lower proof strengths than the horizontal specimens. The laser welds generally exhibited lower microhardness, proof strengths and fracture strains than the PBF base metal which correlated with the observed structure. This work has demonstrated that PBF built parts can be joined by laser welding to form larger components and provided insight into the resulting strength and ductility

Birth cohort effects on the quantity and heritability of alcohol consumption in adulthood : a Finnish longitudinal twin study

Aims To estimate birth cohort effects on alcohol consumption and abstinence in Finland and to test differences between birth cohorts in genetic and environmental sources of variation in Finnish adult alcohol use. Design The Older Finnish Twin Cohort longitudinal survey study 1975-2011. Setting Finland. Participants A total of 26 121 same-sex twins aged 18-95 years (full twin pairs at baseline n = 11 608). Measurements Outcome variables were the quantity of alcohol consumption (g/month) and abstinence (drinking zero g/month). Predictor variables were 10-year birth cohort categories and socio-demographic covariates. In quantitative genetic models, two larger cohorts (born 1901-20 and 1945-57) were compared. Findings Multi-level models in both sexes indicated higher levels of alcohol consumption in more recent birth cohorts and lower levels in earlier cohorts, compared with twins born 1921-30 (all P < 0.003). Similarly, compared with twins born 1921-30, abstaining was more common in earlier and less common in more recent cohorts (all P < 0.05), with the exception of men born 1911-20. Birth cohort differences in the genetic and environmental variance components in alcohol consumption were found: heritability was 21% [95% confidence interval (CI) = 0-56%] in the earlier-born cohort of women [mean age 62.8, standard deviation (SD) = 5.3] and 51% (95% CI = 36-56%) in a more recent cohort (mean age 60.2, SD = 3.7) at the age of 54-74. For men, heritability was 39% (95% CI = 27-45%) in both cohorts. In alcohol abstinence, environmental influences shared between co-twins explained a large proportion of variation in the earlier-born cohort (43%, 95% CI = 23-63%), whereas non-shared environmental (54%, 95% CI = 39-72%) and additive genetic influences (40%, 95% CI = 13-61%) were more important among more recent cohorts of men and women. Conclusion The contribution of genetic and environmental variability to variability in alcohol consumption in the Finnish population appears to vary by birth cohort.Peer reviewe

Hunting cultures and the ‘northern periphery’ : Exploring their relationship in Scotland and Finland

Acknowledgements The authors are grateful to everyone they worked with during the research on which this paper is based and to the Northern Periphery Programme (2007-13) for funding it.Peer reviewedPostprin