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The olive oil mill wastewater (OMW) is a by-product (with a high organic load) derived from the production of the olive oil. The OMW steam reforming (OMWSR) process was studied herein, aiming to decrease the environmental damage of such effluents; simultaneously, the waste is economically and energetically valorized with the H-2 production. Several Ni-containing catalysts were prepared and tested to compare their performances for the OMWSR using a synthetic OMW effluent; still, stability tests were also carried out. The materials were extensively characterized: thermogravimetric analysis, temperature programmed oxidation/reduction, temperature-programmed desorption of CO2/NH3, chemisorption of H-2, inductively coupled plasma optical emission spectrometry and physical adsorption-desorption of N-2 at-196 & DEG;C. Amongst the materials tested, the Ni-Ru/SiO2 sample stood out, exhibiting high catalytic performance: at 400 & DEG;C, the H-2 yield (> 8 mol(H2)& BULL;mol(OMW)(-1)) and conversion of total organic carbon (asymptotic to 75%) were high during all the 24 h of the long-term test, with only a small deactivation being noticed.

Organic photovoltaics (OPV) have developed into a vast research area. Progress in various directions has made it difficult to monitor the technology's precise development state. We offer a patent landscape analysis over all OPV devices, their substrates and encapsulation materials to provide an overview of patenting activity from a historical, organizational, geographical and technological point of view. Such an exercise is instrumental for private companies and research institutes aiming at both internal or external technology creation. We discuss our findings in the context of the Industrial Life Cycle model and find OPV still residing in the fluid technology development phase. Technology development is still following an exponential growth path, with the majority of patents coming from the Asian continent and in general private companies. For devices, the main technological focus can be traced back to the " H01L-031" international patent classification (IPC) main group. For the queried substrates, the most attention has gone to glass, but paper and textile have drawn significant interest too. Finally, encapsulation is found to be a less mature research field given the smaller number of patent families. The latter shows that the technology has not matured to the level where processing is carried out on a commercial scale

Hydraulic experiments using physical scale models of monopile scour protections typically have high ex-perimental uncertainties and data scattering. These uncertainties may severely affect the accuracy of the experimental results and need to be analysed quantitatively. This paper presents a study on the quantification of experimental uncertainties in monopile scour protection damage tests following the Guide to the expression of Uncertainty in Measurement (GUM) (ISO, 2008). The uncertainty analysis is performed using the three-dimensional damage number S3D and the widely applied STAB number. Through the analysis of the S3D number from individual test and repeated tests, it is found that the uncertainty analysis method for an individual test can be efficiently applied to predict the experimental uncertainty. The wave peak period and the current velocity are identified as the two major sources of uncertainties for the S3D number. The flow turbulence and correlations between input parameters can be neglected when estimating the uncertainty. The uncertainty analysis of the STAB number shows that the experimental uncertainty due to measurement can be up to 5% to 7% of the obtained STAB result. This uncertainty range is wide in comparison with the narrow margin of a dynamic scour protection design in DNV's recent recommended practice (DNV-RP-0618). The uncertainty of the STAB number is more affected by the armour stone density, wave peak period and significant wave height.

Abstract Regulatory risk is commonly accepted as one of the most important risks in the energy business, particularly renewable energy. With the recent changes (in June 2014) in the Spanish regulatory framework, investors' returns might be significantly affected. Further, as the Spanish and the Portuguese electricity systems are integrated, a change in the regulatory framework of Spain might also affect renewable energy policies and investment strategies in Portugal. This study is a projection of business risk under the assumption that the Portuguese government may adopt similar regulatory changes. Monte Carlo method is used to simulate the data under different scenarios. Applying Net Present Value and Real Options approaches, a 50 MW wind power project is evaluated. This study has considered the delay option to study five regulatory scenarios. A higher value for the delay option suggests that a high financial loss is expected if new wind power projects of similar capacity are implemented under the new regulatory framework.

Abstract Currently, the Algerian energy system relies almost exclusively on fossil resources, but a new paradigm is emerging in the country. The Algeria program on renewable energy and energy efficiency established the ambitious goal of deriving 40% of electricity production from renewable energy sources (RES) by 2030. This study addresses the sustainability objectives of this program using a methodology, which combines an analytic hierarchy process (AHP) and experts’ feedback to evaluate different renewable energy options. The performance of different RES options was assessed against 13 sub-criteria reflecting social, environmental, economic and technical concerns. The results highlighted the importance of social and environmental criteria as the main drivers for the obtained final ranking, with three of these sub-criteria weighting 35% in the decision process. Solar power was shown to be particularly well suited for Algeria, outperforming most of the other renewable options in a large set of highly weighted criteria. Wind power ranked second, followed by biomass, geothermal and lastly by hydropower. Wind and solar power together achieved a total score of more than 0.5 out of 1. From the results, policy implications were drawn and directions for future research were suggested.

Abstract Building-Integrated (BI) solar thermal are systems which are integrated into the building, are a new tendency in the building sector and they provide multiple advantages in comparison with the Building-Added (BA) solar thermal configurations. The present investigation is a critical review about Life Cycle Analysis (LCA) studies of solar systems. Emphasis is given on the BI solar thermal installations. Studies about BA configurations and systems which produce electrical (or electrical/thermal) energy are also presented in order to provide a more complete overview of the literature. The influence of the BI solar thermal systems on building environmental profile is also examined. Critical issues such as ongoing standardization and environmental indicators are discussed. The results reveal that there is a gap in the field of LCA about real BI solar thermal (and solar thermal/electrical) installations. Thus, there is a need for more LCA studies which examine the BI solar thermal system itself and/or in conjunction with the building. Active systems which could provide energy for the building would be interesting to be studied. Investigations about the influence of the BI solar thermal systems on building life-cycle performance could also provide useful information in the frame of a more sustainable built environment.

Abstract A mathematical model was developed to simulate solar drying of grapes, integrating heat and mass transfer models solved by an explicit finite differences method, considering changing boundary conditions. The model simultaneously incorporated shrinkage of the product, changes in effective moisture diffusivity and dependence of thermal properties on water content and temperature. Field experiments were carried out in a mixed mode solar dryer located in the North of Portugal, with pre-blanched grapes. A good prediction of experimental solar drying curves was attained. The mathematical model can be applied for simulating solar drying of different foods, once known their specific thermo-physical properties. Simulations obtained with the developed model can be valuable for predicting accurate drying times and consequently to design, control and optimise the production of dried foods.