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Abstract Reaching universal access to electricity by 2030 requires a massive deployment of mini-grids in rural areas of developing countries. Among the many challenges hindering this process, there are the high uncertainties in assessing demand patterns in rural communities, the costs of field survey campaigns, and the absence of ample and reliable datasets coming from existing projects. This paper tries to address these issues by presenting and discussing a database of load profiles from sixty-one off-grid mini-grids from developing countries worldwide, gathered from the literature, private developers and fieldworks, and reported with technical, socio-economic and geographical characterization factors. A clustering procedure led to the identification of five archetypal load profile clusters, which are presented and analyzed together with their load duration curves. Subsequently, the distribution among the clusters of the various characterization factors selected is studied. The proposed approach allows to widen the range of load profiles usually considered, and to seek correlations between the load profile shapes, the peak power and average energy consumption per connection, the number of customers, the age of measurement, geographical position, operator model, type of tariff and generation technologies present. This work establishes a first step in the creation of a shared database for load profiles of rural mini-grids, helping to overcome the lack of available data and difficulties of demand assessment, proposing original insights for researchers to understand load patterns, and contributing to reduce risks and uncertainties for mini-grid developers.

Abstract The vortex-induced forces on an extruded cylinder with a span of two diameters representative of a finite segment of a non-tapered wind turbine tower at a very high Reynolds number (Re = 8.0×106) are numerically investigated using an incompressible Navier-Stokes flow solver with an Improved Delayed Detached Eddy Simulation (IDDES) turbulence model and correlation-based boundary layer transition modelling. The solution shows spanwise correlated structured vortex shedding with the Strouhal number St = 0.48. The boundary layer transition is found to occur at θ transition = 70 ◦ , and boundary layer separation is found to occur at θ separation = 120 ◦ . Results from the grid dependency study strongly imply that when using IDDES, the Strouhal number converges to higher values than previously reported by the literature as the grid is refined, with results ranging from St ∼ 0.44 using a grid with 4.2 × 106 cells, to St = 0.48 for the finest considered grid with 33 × 106 cells. This behaviour is not seen for URANS, where St = 0.33 for the finest grid.

Nail polish, in particular gel nail polish, is the most used cosmetic product. The components of the gel polish, which determine both toxicity and consumer color properties, are pigments. Zn-Al layered double hydroxides intercalated with anionic food dyes are promising pigments for use in gel polish. The parameters of the samples of Orange Yellow S-intercalated Zn-Al (Zn:Al=4:1 and Zn:Al=2:1) hydroxides synthesized at pH=8 and pH=11 were studied. The crystal structure of the samples was studied by X-ray phase analysis and thermogravimetry, and the pigment properties – by the method of measuring and calculating color characteristics in the CIELab and XYZ systems. The color characteristics of gel nail polish samples prepared using synthesized pigments were studied in a similar way. X-ray phase analysis and thermogravimetry showed that Zn-Al-Orange Yellow S pigments synthesized at both Zn:Al ratios and pH were layered double hydroxides with the α-Zn(OH) 2 structure. The phenomenon of the decomposition of Zn-Al LDH to ZnO during the synthesis was revealed. As a result, all Zn-Al-Orange Yellow S pigment samples contained both layered double hydroxide and zinc oxide. It was shown that all samples of the Zn-Al-Orange Yellow S pigment obtained at pH 8 and 11 and the ratios Zn:Al=4:1 and Zn:Al=2:1 had high pigment characteristics and are promising for use in gel polish. The samples of gel nail polish with synthesized pigments have a red-orange color (сolor tone 595–604 nm) with high monochromaticity (color purity 63–75 %) and color saturation (48.7–58.3)

As part of the Copenhagen Accord, individual countries have submitted greenhouse gas reduction proposals for the year 2020. This paper analyses the implications for emission reductions, the carbon price, and abatement costs of these submissions. The submissions of the Annex I (industrialised) countries are estimated to lead to a total reduction target of 12-18% below 1990 levels. The submissions of the seven major emerging economies are estimated to lead to an 11-14% reduction below baseline emissions, depending on international (financial) support. Global abatement costs in 2020 are estimated at about USD 60-100 billion, assuming that at least two-thirds of Annex I emission reduction targets need to be achieved domestically. The largest share of these costs are incurred by Annex I countries, although the costs as share of GDP are similar for Annex I as a group and the seven emerging economies as a group, even when assuming substantial international transfers from Annex I countries to the emerging economies to finance their abatement costs. If the restriction of achieving two-thirds of the emission reduction target domestically is abandoned, it would more than double the international carbon price and at the same time reduce global abatement costs by almost 25%.

The increasing depletion of natural resources, combined with a wider set of pressures on the environment, has, in recent years, highlighted the need for a more efficient use of energy and a development process that involves alternative energy sources. Energy efficiency has received much attention as a solution, implying both monetary and emissions savings. However, the latter may be partially offset by the income and demand effects of the former, both in more efficient sectors and in spreading to the wider economy. This is the problem of rebound effects. Taking Spain as a case study, and introducing an energy-related CGE model that develops the inclusion of renewables, this paper evaluates a combination of efficiency initiatives to deliver both reduced energy use by households and a more sustainable supply of energy. Our findings suggest that a package aimed at improving efficiency in household electricity and petroleum use, combined with a more competitive supply of energy from renewable sources, may be the only way to get reductions in all energy use, and thus benefit the economy. Specifically, we consider how this package may lead to positive economic impacts and associated rebound effects, where the latter are focused on a greener energy supply.

The hygrothermal behaviour of an internally insulated historic wall is still hard to predict, mainly because the physical characteristics of the materials composing the historic wall are unknown. In this study, the hygrothermal assessment of an internally thermal insulated masonry wall of an historic palace located in Ferrara, in Italy, is shown. In situ non-destructive monitoring method is combined with a hygrothermal simulation tool, aiming to better analyse and discuss future refurbishment scenarios. In this context, the original U-value of the wall (not refurbished) is decreased from 1.44 W/m2K to 0.26 W/m2K (10 cm stone wool). Under the site specific conditions of this wall, not reached by the sun or rain, it was verified that even in the absence of vapour barrier, no frost damage is likely to occur and the condensation risk is very limited. Authors proposed further discussion based on simulation. The results showed that the introduction of a second gypsum board to the studied technology compensated such absence, while the reduction of the insulation material thickness provides a reduction of RH peaks in the interstitial area by 1%; this second solution proved to be more efficient, providing a 3% RH reduction and the avoidance of further thermal losses.

The integration of Grid-Connected PV systems into buildings or public areas is one of the most usual applications of the photovoltaic solar energy in developed countries. Since early 2009, the University is working on an ambitious project, the so-called UNIVERSOL project, where its main goal is to convert the University Campus in a big public area which combines the PV electricity generation with the common uses of a university place. The aim of this paper is to show to the scientific community the main results of this project and that the methodology proposed for the “large urban-area photovoltaic potential” estimation can be easily exportable to other locations with similar characteristics, so the photovoltaic generators integration examples proposed in this project, and the software tools used to represent it, can be helpful for other designers, taking into account that this project has been adapted to the new Spanish legislation. 26th European Photovoltaic Solar Energy Conference and Exhibition; 4068-4072

Energy system modeling has a central role in assessing the future energy system and helping policy makers to set targets and subsidizing mechanisms. In the years, different energy system models have been developed with the aim of supporting political decision-makers in the design of energy policies. It is relevant to compare and cross-validate these models in order to add robustness to the final results and technical feasibility of the identified transition pathways. Two main methods to compare these models exist i) comparison of the technical features and characteristics of the models and ii) comparison of the final results. While there are several reviews focusing on the comparison of models based on their technical characteristics and features, to the authors’ knowledge, no review article exists on comparison techniques based on final results. The scope of this paper is to carry out a review of existing methods and techniques to compare energy system frameworks, models, and scenario results regarding their final results. ; sì