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This document contains the Strategic Research Agenda to Innovation on Blue Energy developed in the framework of the PELAGOS project (D.4.2.1). Relying on both the current Research & Innvation guidelines and priorities established at European level for exploitating in the most effective way the potential of Ocean Energy and the knowledge acquired the activities of PELAGOS project at Mediterranean level, this document considers the strategic focus areas related to the most promising Marine Renewables Energy technologies in the Mediterranean area.

The production of biofuels from renewable sources is a major challenge in research. Methanol, ethanol, dimethyl ether (DME), synthetic natural gas (SNG), and hydrogen can be produced from syngas which is the result of the gasification of biomasses. Syngas composition varies according to the gasification technology used (such as fixed bed reactors, fluidized bed reactors, entrained flow reactors), the feedstock characteristics, and the operating parameters. This paper presents a review of the predominant biomass gasification technologies and biofuels obtained from syngas by biomass gasification. © 2018 by the authors.

This work analyzes the environmental impacts of milk production in an intensive dairy farm situated in the Northern Italy region of the Po Valley. Three manure management scenarios are compared: in Scenario 1 the animal slurry is stored in an open tank and then used as fertilizer. In scenario 2 the manure is processed in an anaerobic digestion plant and the biogas produced is combusted in an internal combustion engine to produce heat (required by the digester) and electricity (exported). Scenario 3 is similar to scenario 2 but the digestate is stored in a gas-tight tank.In scenario 1 the GHG emissions are estimated to be equal to 1.21kgCO2eq.kg-1 Fat and Protein Corrected Milk (FPCM) without allocation of the environmental burden to the by-product meat. With mass allocation, the GHG emissions associated to the milk are reduced to 1.18kgCO2eq.kg-1 FPCM. Using an economic allocation approach the GHG emissions allocated to the milk are 1.13kgCO2eq.kg-1 FPCM. In scenarios 2 and 3, without allocation, the GHG emissions are reduced respectively to 0.92 (-23.7%) and 0.77 (-36.5%)kgCO2eq.kg-1 FPCM. If land use change due to soybean production is accounted for, an additional emission of 0.53kgCO2eq. should be added, raising the GHG emissions to 1.74, 1.45 and 1.30kgCO2eqkg-1 FPCM in scenarios 1, 2 and 3, respectively.Primary energy from non-renewable resources decreases by 36.2% and 40.6% in scenarios 2 and 3, respectively, with the valorization of the manure in the biogas plant.The other environmental impact mitigated is marine eutrophication that decreases by 8.1% in both scenarios 2 and 3, mostly because of the lower field emissions.There is, however, a trade-off between non-renewable energy and GHG savings and other environmental impacts: acidification (+6.1% and +5.5% in scenarios 2 and 3, respectively), particulate matter emissions (+1.4% and +0.7%) and photochemical ozone formation potential (+41.6% and +42.3%) increase with the adoption of a biogas plant. The cause of the increase is mostly emissions from the CHP engine. These impacts can be tackled by improving biogas combustion technologies to reduce methane and NOx emissions. Freshwater eutrophication slightly increases (+0.8% in both scenarios 2 and 3) because of the additional infrastructures needed.In conclusion, on-farm manure anaerobic digestion with the production of electricity is an effective technology to significantly reduce global environmental impacts of dairy farms (GHG emissions and non-renewable energy consumption), however local impacts may increase as a consequence (especially photochemical ozone formation). © 2014 Elsevier B.V.

Saharan anthropic deposits from archaeological sites, located along wadis or close to lakes, and sedimentary sequences from permanent and dried basins demonstrate that water has always been an attractive environmental feature, especially during periods of drought. This paper reports on two very different examples of Holocene sites where “humans and water” coexisted during dry periods, as observed by stratigraphic, archaeological and palynological evidence. Independent research was carried out on the Jefara Plain (Libya, 32°N) and the Gobero area (Niger, 17°N), at the extreme northern and southern limits of the Sahara, respectively. The histories of the Jefara and Gobero areas, as revealed by the archaeological and palaeoenvironmental reconstructions, suggest that these areas were likely to have been visited and exploited for a long time, acting as anthropic refugia, and therefore they have been profoundly transformed. Human presence and actions have conditioned the local growing of plants and selected a more or less synanthropic flora. Today, modern conservation strategies should take into consideration that water reservoirs, which are crucial for the long-term conservation of biodiversity, have provided refugia in the past just as they presently do under global warming conditions. © 2015, Archaeological Centre Olomouc. All rights reserved.

There is a perceived need for multi-fuel burner geometries capable of operating with variable composition fuels from diverse sources to achieve fuel flexibility in gas turbines. The objective of the research covered herein is a comparison study between two liquid fuels, a biodiesel (in a pure form) and the biodiesel as a saturated mixture with a pyrolysis by-product; these two fuels were compared against a standard kerosene as a baseline. The research methodology involved two stages: firstly atomization patterns and injection regimes were obtained using a high speed imaging method, secondly a combustion test campaign was undertaken using a swirl burner to quantify the operational behaviour, species production and exhaust gas compositions of the fuels. Emissions, flame stability trends and power outputs were measured at gas turbine relevant equivalence ratios. Excess oxygen and atomization trends in the biodiesel seem to be playing a major role in the production of emissions and flame stability when compared to kerosene. Also, heavy organics seem to be acting as catalytic substances for OH production close to the burner mouth. In terms of stability and combustion, it is proposed that the saturated blend would be a viable candidate for power generation. © 2016

Time-of-use (TOU) energy cost management involves the use of energy storage systems (ESSs) by customers to reduce their electricity bills. The ESS is charged during off-peak time periods, when electricity energy prices are low, and discharged during times when on-peak energy prices are applied. This article addresses the question whether it is economically viable to install medium-scale distributed ESSs designed to lower the electricity cost for a customer-side application, assuming flexible electricity tariffs. The technical/economical evaluation is carried out referring to lithium-ion (Li-ion), sodium sulfur (NaS) and vanadium redox battery (VRB) technologies, performing a parametric analysis by changing the capital cost of the batteries and the difference between the maximum and minimum electricity price. A case study is performed to show the advantages/disadvantages of the proposed approach. The analysis reveals that, at the current costs of ESSs, the use of batteries for TOU applications is economically advantageous for a public institution facility in Italy only if there is a significant difference between the maximum and the minimum electricity price. The decrease in the cost of storage, stimulated by the implementation of support policies, will make ESS even more convenient for load shifting applications. © 2015 Elsevier Ltd. All rights reserved.

In the biodiesel production, via transesterification, physical methods have been tested to improve efficiency. In this research activity, the microwave have been tested to reduce the reaction time in a continuous process. Moreover, ultrasound utilization has been investigated as effective in order to improve biodiesel synthesis via transesterification process. Experiments have been carried out at bench scale by using soybean oil and methanol (molar ratio alcohol/oil 6:1); as catalyst 1% NaOH or 10% triphosphate potassium were used. For microwave tests, reactants have been injected in a 5.0 m pipe that was inserted in a microwave oven; the product has been recovered outside the oven. Obtained results are very promising. Ultrasound experimental tests were carried out in a batch reactor (500 ml flask) with a condenser, hot bath, magnetic stirrer and/or an ultrasound probe system. As matter of fact, experimental tests carried out by using microwave have pointed out that microwaves can be usefully employed to perform the transesterification of vegetable oils and to reduce reaction time. Moreover, ultrasound seems to be more effective than magnetic stirrer. © 2016 ETA-Florence Renewable Energies.

Climate changes and urban sprawl dramatically increase the urban temperatures and the thermal quality in the built environment. Among several proposed mitigation techniques, cool roofs have now reached a broad audience, while the cool materials potentialities for façade applications are still little investigated. A novel masonry paint, produced with the inclusion of cool pigments, is investigated in this paper. A palette of colour is developed with the objective of covering a wide range of architectural integration solutions. Reflectance and emissivity are measured and calculated. The results strongly depend on the base colour used to prepare the sample; solar reflectance increase up to 0.16 is achieved for dark colours. A numerical analysis is carried out to evaluate the impact of the cool paint on the thermal response of a typical Italian residential building. Energy uses are calculated for different insulation levels and climatic conditions. Cooling energy uses are reduced in the 10-20% range; total energy uses are affected by several parameters with 5% maximum savings. Peak operative temperature reductions range from 0.5 to 1.6 °C for the building in free floating conditions, according to climate and insulation level. External surface temperatures are reduced above 6 °C during the peak irradiation hours. © 2015 Elsevier B.V. All rights reserved.

The transfer of chemical vapor deposited graphene is a crucial process, which can affect the quality of the transferred films and compromise their application in devices. Finding a robust and intrinsically clean material capable of easing the transfer of graphene without interfering with its properties remains a challenge. We here propose the use of an organic compound, cyclododecane, as a transfer material. This material can be easily spin coated on graphene and assist the transfer, leaving no residues and requiring no further removal processes. The effectiveness of this transfer method for few-layer graphene on a large area was evaluated and confirmed by microscopy, Raman spectroscopy, x-ray photoemission spectroscopy, and four-point probe measurements. Schottky-barrier solar cells with few-layer graphene were fabricated on silicon wafers by using the cyclododecane transfer method and outperformed reference cells made by standard methods.

This study presents results of two experimental campaigns on a 30 kW air source CO2 heat pump prototype for domestic hot water (DHW) production. The prototype has been realized, tested and optimized within the NxtHPG (Next Generation of Heat Pumps working with Natural fluids), 7th Framework European project. The project aims to reach higher efficiency (10-20% SPF improvement) and lower Carbon footprint (20% lower TEWI) than the current state of the art HFCs/HFOs or Sorption heat pumps, with costs very similar or slightly higher than the latter systems (10%). The tested CO2 heat pump has been designed to produce water at 60°C/80° C starting from a return temperature in the range 10°C/55°C (winter) and 20°C/55°C (summer). First experimental campaign was performed to determine possible issues and potential improvements to be applied on this prototype. In the second experimental campaign, after the required modifications of the prototype, the measured performance, COP and heating capacity, have been in line with objectives. In addition, useful information have been obtained to make additional modifications to further improve the heat pump performance. © 2016, International Institute of Refrigeration. All rights reserved.