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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.

As the availability of fossils fuels becomes more limited, the negative impact of their consumption becomes an increasingly relevant factor in our choices with regards to primary energy sources. The exponentially increasing demand for energy is reflected in the mass generation of by-products and waste flows which characterize current society’s development and use of fossil sources. The potential for recoverable material and energy in these ever-increasing refuse flows is huge, even after the separation of hazardous constituent elements, allowing safe and sustainable further exploitation of an otherwise 'wasted' resource. Fuel Cells in the Waste-to-Energy Chain explores the concept of waste-to-energy through a 5 step process which reflects the stages during the transformation of refuse flows to a valuable commodity such as clean energy. By providing selected, integrated alternatives to the current centralized, wasteful, fossil-fuel based infrastructure, Fuel Cells in the Waste-to-Energy Chain explores how the concept of waste-to-energy can be constructed and developed into a realistic solution. The entire spectrum of current and future energy problems is illuminated through the explanation of the operational, integration and marketing implications of high efficiency technological solutions using the real context of developed regions such as Europe. Up-to-date reviews are provided on the status of technology and demonstration, implementation and marketing perspectives. The detailed technological information and insight gathered from over twenty years of experience in the field makes Fuel Cells in the Waste-to-Energy Chain a valuable resource for all engineers and researchers in the fields of energy supply systems and waste conversion, as well as providing a key reference for discussions by policy makers, marketing experts and industry developers working in energy supply and waste management.

During the project FITOPROBIO, new potential wetland plants were studied to obtain second generation ethanol. The plants were irrigated with wastewater which could be an interesting opportunity of the reuse of poor quality waters and the development of the marginal areas. The agronomic activities took place in two experimental fields (Veneto and Sicily). Twentythree species were characterized in terms of elements and fiber in order to find the best potential ethanol producers. A three-step chemical pretreatment was carried out on bench scale for all the 23 species. First the biomasses were treated with hot diluted acid (H2SO4 2%, T=80°C, t=24h), secondly with diluted NaOH 1% at 40°C for 24h, finally concentrated H2O2 was added until the 1% concentration at t=25°C for 24h. After the chemical pretreatment until the 90% of cellulose was recovered and the 80% of lignin was solubilised. This pretreated material was then hydrolysed with a mix of commercial enzymes (Celluclast 1.5L and Novozym 188) for 72h and afterwards fermented for 24h by means of strain of Saccharomyces cerevisiae isolated in the ENEA laboratories. For each studied plant the yield of ethanol production was calculated. At the end, the best experiments were scaledup on bioreactors of the volume of 2/5 liters. Durante il progetto FITOPROBIO, sono state studiate nuove piante palustri per ottenere etanolo di seconda generazione. Le piante sono state irrigate con acque di scarico che potrebbero rappresentare un’opportunità interessante riguardo al riutilizzo di acque di scarsa qualità e allo sviluppo di zone marginali. Le attività agronomiche sono state svolte in due campi sperimentali (Veneto e Sicilia). Ventitré specie sono state caratterizzate in termini di elementi e fibra in modo da trovare le specie potenzialmente migliori alla produzione di etanolo. È stato sperimentato un pretrattamento chimico di tre fasi, su scala banco per tutte le 23 specie. Dapprima, le biomasse sono state trattate con acido diluito a caldo (H2SO4 2%, T=80°C, t=24h), in seguito con NaOH 1% diluito alla temperatura di 40°C per 24 ore, infine H2O2 concentrato è stato aggiunto fino alla concentrazione dell’1% a t=25°C per 24 ore. Dopo il pretrattamento chimico, è stato recuperato fino al 90% di cellulosa e l’80% di lignina è stata solubilizzata. Il materiale pretrattato è stato idrolizzato con un mix di enzimi commerciali (Celluclast 1.5L e Novozym 188) per 72 ore e in seguito fermentato per 24 ore utilizzando un ceppo di Saccharomyces cerevisiae isolato nei laboratori dell’ENEA. Per ogni pianta studiata, è stata calcolata la resa di produzione dell’etanolo. Infine, i migliori esperimenti sono stati replicati in bioreattori del volume di 2/5 litri.

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.

Abstract: As resources of both water and traditional fuels are becoming increasingly limited, the need for desalination technologies that can operate using sustainable energy is growing. This chapter looks at the major ways in which solar energy, which is particularly promising in this respect, can be integrated with desalination technologies. The chapter first examines the tested desalination techniques of reverse osmosis and (reverse) electrodialysis, which can be powered using photovoltaic systems, and discusses their mechanisms as well as their advantages and disadvantages. The second main focus is on types of solar thermal collectors and their use with membrane distillation technology, which is a less well established but very promising desalination method.

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.