Feasibility study to realize an anaerobc digester fed with vegetables matrices in central Italy

In the present paper we have analysed the possibility to realize an anaerobic digester in a bio-Energy Park located in Città della Pieve, a small town in Central Italy. The use of anaerobic digesters is quite common in Europe for reducing the environmental impact of manure in a co-digestion procedure with vegetables materials. In addition, for several areas of Central Italy there is the need to find alternative productions to improve farmer's incomes, as traditional cropping systems are loosing convenience. An interesting alternative seems to be cultivation of energy crops because of the favourable conditions of the electric energy market. We are suggesting a low input cropping system to be implemented in areas where low input food/feed crops are no more profitable. In particular our case-study is an example based on the use of a forage legume, alfalfa (Medicago sativa L.), together with other crops, like sorghum, to realize small-size bio-digesters plants. Alfalfa: is a highly sustainable crop as it is able to fix nitrogen and therefore it does not require this fertilization with the consequence of avoiding underground water pollution. Moreover alfalfa residual products are nitrogen rich thus improving soil structure and fertility more than popular graminaceous energy crops such as corn. Beside, alfalfa mostly does not need irrigation in the typical Central Italy environment, all these traits make it one of the species with the lowest energy needs for growing. The aims of this feasibility study are: i) optimization of plant materials feeding the bio-digester, ii) typology of bio-digester, iii) size of bio-digester in relation with land availability for growing energetic cultures, iv) the utilization of bio-gas produced by bio-digester plant to produce electric and thermal energy using cogeneration engines, vi) disposal of waste-water produced according to regional and national laws. The final aim of this study is to verify the possibility to develop an alternative economical use of marginal soils in relatively dry areas of Central Italy that would be replicable in other European areas with a similar climatic situation

A Comparison Between the LCA of a PEMFC and an MCFC Systems for the Production of Electric Energy, and Traditional Energy Conversion Systems

This paper investigates the environmental impact of electric energy generation by using a PEMFC and an MCFC system. Fuel cells are considered to be ultra-clean energy conversion devices, since pollutants emissions during operation have a very low concentration, compared to those of traditional energy systems. In order to understand the real environmental impact of fuel cells, this is not enough and it is necessary to study their "cradle-to- grave" life, starting from the construction phase, to the operational life and eventually to its disposal. In fact, it is not really correct to say that fuel cells are almost zero-emission systems, because they produce not-negligible emissions during manufacturing and to produce hydrogen. The method used in this paper is the Life Cycle Assessment (LCA), which has been calculated with the software SimaPro 5.0. The functional unit chosen in this study is the production of 1 kWh of electric energy by a PEMFC and an MCFC. Thanks to this approach, the critical process related to the production of energy by the previous fuel cell systems, (i.e. the production of hydrogen by natural gas steam reforming), has been determined. After a separated LCA of the PEMFC and the MCFC, a comparison was made between the two systems, considering the environmental impact of electric energy generation. Finally, the production of electric energy by a PEMFC and an MCFC systems is compared to that by conventional energy conversion system

A Comparison Between Life Cycle Assessment Of An MCFC System, An LFG – MCFC System, And Traditional Energy Conversion Systems

The present work aims at evaluating the environmental impact caused by fuel cell systems in the production of electric energy. The very low pollutant emission levels in fuel cells makes them an attractive alternative in ultra clean energy conversion systems. Actually, to truly understand the environmental impact related to fuel cells, it is necessary to study their “cradle-to-grave” life, from the construction phase, during the conversion of primary fuel into hydrogen, to its disposal. The tool used in this analysis is the Life Cycle Assessment approach; in particular the environmental impact of a fuel cell system has been simulated through the software SimaPro 5.0. Thanks to this approach, once the critical process regarding the production of energy by fuel cell system, (i.e. the production of hydrogen by natural gas steam reforming), has been determined, an analysis of the use of landfill gas as a renewable source to produce hydrogen was done. Finally, the production of electric energy by fuel cell systems was compared to that by some conventional energy conversion systems. A second comparison was done between the Molten Carbonate Fuel Cell (MCFC) fuelled by landfill gas and natural gas

Comparative analysis of concentrating solar power and photovoltaic technologies: Technical and environmental evaluations

Solar energy is an important alternative energy source to fossil fuels and theoretically the most available energy source on the earth. Solar energy can be converted into electric energy by using two different processes: by means of thermodynamic cycles and the photovoltaic conversion. Solar thermal technologies, sometimes called thermodynamic solar technologies, operating at medium (about 500 C) and high temperatures (about 1000 C), have recently attracted a renewed interest and have become one of the most promising alternatives in the field of solar energy utilization. Photovoltaic conversion is very interesting, although still quite expensive, because of the absence of moving components and the reduced operating and management costs. The main objectives of the present work are: - to carry out comparative technical evaluations on the amount of electricity produced by two hypothetical plants, located on the same site, for which a preliminary design was made: a solar thermal power plant with parabolic trough collectors and a photovoltaic plant with a single-axis tracking system; - to carry out a comparative analysis of the environmental impact derived from the processes of electricity generation during the whole life cycle of the two hypothetical power plants. First a technical comparison between the two plants was made assuming that they have the same nominal electric power and then the same total covered surface. The methodology chosen to evaluate the environmental impact associated with the power plants is the Life Cycle Assessment (LCA). It allows to analyze all the phases of the life cycle of the plants, from the extraction of raw materials until their disposal, following the ‘‘from cradle to grave’’ perspective. The environmental impact of the two power plants was simulated by using the software SimaPro 7.1, elaborated by PRé Consultants and using the Eco-Indicator 99 methodology. Finally, the results of the analysis of the environmental impact are used to calculate the following parameters associated to the power plants: EPBT (Energy Pay-Back Time), CO2 emissions and GWP100 (Global Warming Potential over a 100 year time horizon)

Life cycle assessment of a reflective foil material and comparison with other solutions for thermal insulation of buildings

In the last twenty years, the exploitation of non-renewable resources and the effects of their applications on environment and human health were considered central topics in political and scientific debate on European and worldwide scale. This kind of resources have been used in different sectors, as energy systems, technological research, but also in private/public buildings and production of consumer goods, involving significantly domestic and ordinary life of every human being. Studies about the effect of this exploitation carried out discouraging results, in terms of climate changes and energy sustenance; this determined a progressive approach process to a new concept of development, able to couple the qualitative standard of modern life with the respect of planet and its inhabitants. Starting from this reflection, scientific community moved towards research on alternative resources and developed a new way to conceive planning process and technical innovations, in order to exploit renewable energies and recycled materials, promote energy savings and reduce environmental pollution. In this context the present paper aims at evaluating benefits relating to different solutions of thermal insulation in building envelope. In fact a high grade of insulation ensures better comfort conditions in inner spaces, reducing energy consumptions due to heating and cooling conditioning. The paper presents the results of a detailed Life Cycle Assessment (LCA) of the reflective foil ISOLIVING, conceived and produced by an Italian company. The Life Cycle Assessment methodology allows to consider all stages of the life cycle, from the extraction of raw materials to the product’s disposal, in an optics “from cradle to grave.” In particular, the study takes into account the production phase of the reflective foil ISOLIVING, the installation phase, the transport of all components to the production site and also the end of life scenario of the material. The possibility to collect many detailed information about the production phase adds value to the study. The analysis is carried out according to UNI EN ISO 14040 and UNI EN ISO 14044, which regulate the LCA procedure. The LCA modeling was performed using SimaPro software application. The results of the analysis allow to make an important comparison concerning the environmental performances, between the reflective foil ISOLIVING and other types of insulating materials