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Solar power appears to be one of the most promising resources to meet the medium and long term renewable energy targets. The integration of large amounts of photovoltaic (PV) generation into distribution networks faces some limitations due to the network constraints. The PV community became well aware of these limitations in the last years. While first solutions have been pointed out mainly for large installations connected to the medium voltage network, the specificities of low voltage networks are still not fully understood. This paper aims at explaining the challenges associated to the planning and operation of low voltage network with high PV penetration. The actual impact of PV infeed is quantified on the basis of real and accurate network, load and generation data. Results from unsymmetrical load-flow computations are presented and the implementation of reactive power-based voltage control is shortly discussed. 26th European Photovoltaic Solar Energy Conference and Exhibition; 4469-4478

Recently two approaches to extend the photoluminescence imaging (PLI) technique by evaluating the dynamic properties of the sample have been presented. Time-resolved photoluminescence measurements may provide calibration-free maps of the effective minority charge carrier lifetime in silicon wafers. Due to the transient measurement they minimize errors due to lateral inhomogeneities in setup or sample, which would usually contribute linearly to steady-state PLI measurements. In this work, we will focus on mechanically shuttered time-resolved photoluminescence imaging (TR-PLI), as it provides a high measurement range down to 5 μs at low hardware costs. 26th European Photovoltaic Solar Energy Conference and Exhibition; 1463-1466

Changing PV market conditions foster the use of PV storage systems and bring new challenges to the grid. This paper analyzes the influence of PV and PV battery systems on the voltage unbalance and the voltage magnitude. Different system topologies are evaluated by simulating their behavior in two different test grids. A sensitivity analysis is performed varying the size of the PV system, the size of the battery, the grid penetration of the systems and the phase connection. The analysis shows that voltage unbalance problems can occur in case of same phase connection of the systems. The results suggest that PV battery systems mitigate the problem for the two example grids depending on the PV power and battery size. For grids with equally distributed phase connections of either PV or PV battery systems, no violations of the voltage unbalance criterion are observed. 27th European Photovoltaic Solar Energy Conference and Exhibition; 3822-3828

Purpose:This research aims to develop a framework of sustainability performance measurement and to propose sustainability impact criteria that can be used to meas-ure complex sustainability impacts in the manufacturing industry. Methodology:Fuzzy-Analytical Hierarchy Process (Fuzzy-AHP) and the Delphi method were used to calculate the weights of sustainability impact criteria. Then, the impact pathway of a life cycle assessment was constructed to illustrate the inter-relationship between each impact criterion. A proposed framework of sustainability performance measurement is presented along with the suggested sustainability im-pact criteria.Findings:Based on the Delphi method and Fuzzy-AHP, the environmental aspect is the area that has received the highestconcern (49.4%). The important endpoint im-pact criteria of the environmental aspect consist of Effect on global climate, Ecosys-tem quality, Animal biodiversity, and Resource management. Originality: The biggest challenge of sustainable development that is yet to be an-swered is how to measure sustainability performance. The environmental aspect is the area that has received the most attention while the economic and social aspects are still under-represented. To fill the gap, this research proposes a framework of sustainability performance measurement that considers all interrelationships be-tween each sustainability aspect

The EFQM excellence model is a famous quality management tool. We have translated it to be useful in e-learning quality management. EFQM will be used as a framework for self-evaluation. We developed the e-learning stakeholder model. We identified the main criterion and positioned them in the stakeholder model.We present short the Kirkpatrick evaluation model of e-learning.We developed a Kirkpatrick-EFQM self-assessment framework. We propose the limited learner-centric self-assessment framework. A preliminary set of quality criteria have been identified for self-assessment by the learners.

The increasing importance of turning operations is gaining new dimensions in the present industrial age, in which the growing competition calls for all the efforts to be directed towards the economical manufacture of machined parts as well as surface finish is one of the most critical quality measure in mechanical products. In the present work, empirical models for estimating the surface roughness of machined components under various cutting speed have been developed using regression analysis software. The centre lathe was used to turn the components (stainless steel, mild steel and aluminum cast) at different cutting speed ranging between 76 rev/min to 600 rev/ min at a constant depth of cut of 1 mm/pass and feed rate of 0.5 mm/rev. and surface roughness of machined components measured with a digital portable surface roughness tester (TR100 Model) using centre line average method. The values obtained from the empirical models were found to compare favourably with the experimental values. The Mean Absolute Percent Deviation (MAPD) which measures absolute error as a percentage was found to be 1.46% (stainless steel), 4.55 %( mild steel) and 4.76% (aluminum cast) respectively. These values were insignificant and below the maximum recommended value of 10%. These model performances were therefore found to be satisfactory and show good predictability. @JASEMKeywords: cutting speed, centre lathe, empirical model, surface roughness, Mean absolute percentage deviation