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This paper describes a modelling approach suitable for assessments of future scenarios for renewable energy integration in large and interconnected power systems, based on sequential optimal power flow computations that take into account variability in power consumption, in renewable power production, energy storage, and flexible demand. The approach and the implementation as an open source Python package called Power Grid And Market Analysis is described in some detail. Particular emphasis is put on the modelling of energy storage systems, and the use of storage values as a means to define storage utilisation strategies. A case study representing a 2030 scenario for the Western Mediterranean region is then analysed using this approach. The main aim of this study is to assess the benefit for the system of adding flexibility in terms of storage associated with concentrated solar power or flexible demand. But other results are also presented, such as the resulting energy mix, generation costs, price variations, and grid congestion. [ABSTRACT FROM AUTHOR]

The main purpose of this paper is to examine the energy efficiency determinants in Mediterranean countries over 2009-2012. In order to account for both the bias and serial correlation of efficiency scores, we use the double bootstrap procedure suggested by Simar and Wilson (2007) which allows for valid inference. By using a specific bootstrap procedure in the first stage, the DEA efficiency estimator is corrected for the bias. A parametric bootstrap procedure is also applied, in the second stage analysis, to the truncated regression of DEA bias-corrected efficiency scores on environmental variables. In the first stage, empirical findings show that energy efficiency levels in the Mediterranean countries are high and declining over time. The results of the second stage analysis reveal that the gross national income per capita, the population density, and the renewable energy use impact energy efficiency. Finally, the study provides policy implications for future improvement of energy efficiency. [ABSTRACT FROM AUTHOR]

Sustainable energy planning includes various requirements, conflicting or not. Thus, any decision making is directly related to analytical procedures and management of a wide range of information (technological, environmental, economic and social). Multi-criteria analysis is a valuable tool, which is suitable to assemble and to manage many variables (quantitative as well as qualitative ones), assessed in different ways, thus offering reliable support for decision making. This analysis scopes to facilitate the photovoltaic (PV) integration in buildings, which combines benefits from shading, power generation, and esthetics. This paper performs a multi-criteria analysis of monocrystalline PV panels mounted on typical south-facing shading devices of office buildings in the Mediterranean region. In total, thirteen different options of shading devices were assessed against a series of criteria which include PV panels’ energy production, buildings’ energy optimization criteria (heating–cooling–lighting loads) and users’ comfort criteria (outdoor view–glare–esthetic aspects). Six different rankings were obtained by the analysis, each one reflecting the priorities and interests of different economic and social groups involved in the design and promotion of integrated PV systems in buildings. The analysis revealed that “Brise soleil full façade” is the most proper shading device when the PV system is mounted on it; in contrary “Canopy inclined double” or “Louvers horizontal inwards inclined” or “Simple window” seem to be the least suitable. [ABSTRACT FROM AUTHOR]

In this scientific paper, the quantitative and qualitative performances of three different de-stoner machines involved in an industrial olive oil plant were evaluated. The bioenergy production potential for olive stone in Italy was also estimated. The results confirmed that the best performance was obtained using the innovative partial de-stoner machine called “Moliden” because it does not lead to losses in oil extraction efficiency (as opposed to the total de-stoner machine) and it also extracts an amount of olive stone (approximately 65% of the total stone contained in the olives) that is greater than that obtained using the husk de-stoner machine (58%). In addition, the olive stone obtained by using a partial de-stoner machine contains lower oil, fine particle sizes and nitrogen compared to the olive stone obtained by using a husk de-stoner machine. This leads to advantages regarding combustion efficiency and the environment. Considering the olive production in Italy and in the Mediterranean basin, olive stone might be an attractive renewable source for energy production. [ABSTRACT FROM AUTHOR]

In the Mediterranean region, there are many drip irrigation systems with pumps that are powered by diesel generator sets (gensets). Although they could be powered by renewable energy produced on-site, technical and economic factors make that difficult. Moreover, the seasonal nature of demand requires an oversizing of energy generation and/or storage, increasing system costs. In this paper, we sought renewable energy systems that were economically optimal. We focused on six farming facility case studies to find the optimal energy generation solution using a simulation and optimization tool based on genetic algorithms. Photovoltaic-diesel hybrids and diesel systems were found to be optimal, with energy costs from 0.13 to 1.08 €/kWh and from 0.32 to 0.52 €/kWh, respectively. The strong effect of demand management was an interesting finding, as it may indicate significant system size and cost reductions. In addition, the optimum photovoltaic fixed tilt angles depended not only on the seasonal profile of the demand, but also on the pumping schedule. Although the difference between market interest rates and the rise of fuel prices strongly influences the advantage of incorporating, or not, renewable generation, this study supports that hybrid photovoltaic-diesel systems can make profitable use of renewable energy in drip irrigation. [ABSTRACT FROM AUTHOR]

Abstract: Several European initiatives consider the electrical integration of the Euro-Mediterranean region a key priority for meeting future European Union (EU) energy policy goals. Ambitious plans include the development of Renewable Energy Sources (RES) in the region as well as transmission interconnectors between the two shores of the Mediterranean Sea. The success of such initiatives, in addition to several techno-economic, political, environmental, regulatory and financial obstacles, depends on the ability of the European electricity network to suitably accommodate large electricity imports from North Africa. In order to address the issue, this paper, based on the combination of two methodologies, presents a first techno-economic analysis of the effects of electricity imports from North Africa on the European and the Italian power systems in 2030. Within a common framework, the adopted approach has proved its feasibility with coherent results showing a decrease in electricity prices in Europe. The European study shows how net electricity exchanges tend to follow the direction from South to North. The impact of North-African electricity on the Italian system is relevant. Also, Italy''s potential of becoming a Mediterranean electricity hub is emphasised. National internal grid congestion results to be a crucial issue for the Euro-Mediterranean electrical integration. [Copyright &y& Elsevier]

Abstract: Over eight million hectares of olive trees are cultivated worldwide, especially in Mediterranean countries, where more than 97% of the world’s olive oil is produced. The three major olive oil producers worldwide are Spain, Italy, and Greece. Olive tree pruning residues are an autochthonous and important renewable source that, in most of cases, farmers burn through an uncontrolled manner. Besides, industrial uses have not yet been developed. The aim of this paper consists of a new calculation tool based on particles swarm (Binary Honey Bee Foraging, BHBF). Effectively, this approach will make possible to determine the optimal location, biomass supply area and power plant size that offer the best profitability for investor. Moreover, it prevents the accurate method (not feasible from computational viewpoint). In this work, Profitability Index (PI) is set as the fitness function for the BHBF approach. Results are compared with other evolutionary optimization algorithms such as Binary Particle Swarm Optimization (BPSO), and Genetic Algorithms (GA). All the experiments have shown that the optimal plant size is 2MW, PI =3.3122, the best location corresponds to coordinate: X =49, Y =97 and biomass supply area is 161.33km2. The simulation times have been reduced to the ninth of time than the greedy (accurate) solution. Matlab® is used to run all simulations. [Copyright &y& Elsevier]

Abstract: Trigeneration systems, also known as Combined Heat, Cooling and Power (CHCP) systems, are interesting alternatives to supply different energy services in urban districts and in large buildings, particularly in warm areas such as Mediterranean countries. These systems can provide substantial benefits from economic, energetic, and environmental viewpoints, since the cogenerated heat can be used for heating in winter as well as cooling in summer with an absorption refrigerator. This paper develops an optimization model using Mixed Integer Linear Programming (MILP) to determine the type, number and capacity of equipment in CHCP systems installed in the tertiary sector as well as to establish the optimal operation mode for the different plant components on an hour-by-hour basis throughout the year. The objective function to be minimized is the annual total cost. The optimization model considers the legal constraints imposed to feed the surplus autogenerated electricity into the grid at a regulated feed-in tariff. The optimization model is applied to design a system providing energy services for a hospital located in the city of Zaragoza (Spain). The effects of the financial market conditions and energy prices in the optimal structure of the system are analyzed. [Copyright &y& Elsevier]

This work focuses on projecting wind resources over a marine area that was shortlisted as a possible offshore wind farm site in inshore Maltese territorial waters. Wind measurements conducted over the 24 calendar month period from November 2009 to October 2011 were sourced from an 80 metre wind monitoring mast installed onshore close to the proposed offshore wind farm's location. This study uses a combination of Measure-Correlate-Predict (MCP) techniques in conjunction with commercial Computational Fluid Dynamics (CFD) software. MCP routines were conducted between an inland reference wind measurement station possessing a long-term wind speed and direction time series and the shorter-term 80 metre wind mast's database; with the latter assuming the role of candidate site. A procedure was followed to generate a long-term wind climatology at the candidate site. This climatology was subsequently used to calibrate CFD flow modelling software to generate a wind resources map within a coastal environment of an island archipelago in the central Mediterranean region. [ABSTRACT FROM AUTHOR]

The most recent European (Directive 2006/32/CE of April 5/2006 relating to the efficiency of the final uses of the energy and the energetic services) and national (Decree 311/06) normatives impose the use of energetic systems more efficient that minimize the use of fossil fuels in comparison to the use of renewable energy. In this research a comparison was developed between the traditional electric equipments (which use vapour compression) and the absorption equipments (powered by solar thermal energy). This comparison was implemented considering the energetic, economic and environmental aspects. This research explores the technical - economic potentialities of solar HVAC systems, with particular reference to those based on the absorption cycles, verifying the possible applications in regions of the Mediterranean area (in particular Madrid, Palermo and Athens). In particular we define an economic index and an environmental-energetic index. [ABSTRACT FROM AUTHOR]