Suchergebnisse

In the near future, renewable energies will have a decisive role to play in attempts to achieve the ambitious objectives fixed by the European Union. Consequently, not only the economic aspect but also energy and environmental issues of agroenergy chains (AEC) must be carefully evaluated. Software (SE3A) able to assess economic, energy and environmental performance of AEC has been developed. The aim of this paper is to present SE3A and show its usefulness in evaluating different AEC and/or different technical solutions. For the moment, the analysis is restricted to: i) field and ii) post-harvest (transport/storage) phases of the AEC. As an example of SE3A flexibility, economic, energy and environmental costs (EEE costs) related to the cultivation technique used in northern Italy for the poplar short rotation coppice were evaluated.

In the near future, the role that renewable energies can play in order to achieve the ambitious objectives fixed by the European Union is decisive. Besides economic aspect also energetic and environmental issues of agro-energy chains must be carefully evaluated. We developed a software tool able to assess economic, energetic and environmental performance of renewable energy from biomass. The aim of this paper is present the software and its application about one of the most promising energy crop in Italy: Short Rotation Coppice (SRC) based on poplar clones. SRC, subdivided into SRF – plantation with a short cutting frequency (1 or 2 yrs) and in MRF – plantation with a medium cutting time (5 yrs), takes up about 7,000 hectares in Italy. Twenty years after their introduction, in bibliography the information concerning this crop is not always clear and unanimous. On the basis of the cultivation technique carried out in Northern Italy, an economic, energetic and environmental (EEE) evaluation of the poplar SRC (SRF and MRF) has been carried out. The analysis is focused on field and transport phases of the agro-energy chain.

Earthworms for feed production from vegetable waste: environmental impact assessment Cecilia Conti, Jacopo Bacenetti, Doriana Tedesco Department of Environmental Science and Policy, Universit degli Studi di Milano, Via G. Celoria 2, Milan, 20133, Italy Abstract In the European Union, 88 million tons of food is wasted annually, 30% of which comes from the production and processing sectors. Among the different food waste, vegetable ones represent a remarkable share and their management is complicated by the usually high-water content and the difficult storage. In this context, the earthworms are an interesting solution because transform vegetable waste into valuable products: the vermicompost, that can be sold as organic fertilizer, and the earthworms that, thanks to their high protein content can be used for feed and food production. This study aims to evaluate the environmental impact related to the production of vermicompost and dry earthworm meal. LCA approach was applied, 1 kg of dry meal for feed production was selected as functional unit. Inventory data were collected during experimental tests carried out in 2017 in a composting plant located in Northern Italy where earthworms were fed with vegetable waste. Secondary data were used about emissions during earthworms rearing. A quantity of 1 kg of fresh earthworms (16% of dry matter with 67% of protein content) and 13 kg of vermicompost were produced from 45 kg of vegetable wastes. Between earthworm rearing and processing, the first one is the main responsible for the environmental impact for all the evaluated impact categories except for freshwater eutrophication and ecotoxicity. GHG emissions during composting are the main hotspots for Climate Change.

In recent years, the increasing market trend of Renewable Energy Sources (RES) in the European Union has been connected with the public subsidies guaranteed to encourage their production. In Italy, the northern regions have played a leading role and contributed deeply to increase the share of RES in the national energy mix. An increase in the number of Anaerobic Digestion (AD) plants fed with agricultural feedstock has been detected, reaching 1800 units in only 20 years. AD is considered as one of the most promising technologies for RES production, especially when wastes are used as feed. In fact, the use of wastes brings to increase the added value and reduces the economic and environmental costs related to the waste treatment as well as the energy purchase. Despite these advantages, the economic subsidy framework has encouraged entrepreneurs to increase the productivity of plants by using dedicated crops as feed, of which maize silage is the most widely used. Since the economic subsidy for bioenergy production has already been reduced, it can be expected its end in the future, thus potentially making the feeding of plants with dedicated crops uneconomic. In particular, subsidies could be essential to guarantee revenues and to cover the feeding supply costs. This study aims to evaluate the consequences of the potential deletion of the subsidy framework for AD production plants. Consequential life cycle assessment (cLCA) method was implemented in order to evaluate the environmental effects related to: (i) the substitution of dedicated crops in the feeding mix with pig and cow slurry; (ii) the end of plants fed with dedicated crops and the substitution of the related renewable energy production with non-renewable energy in the national energy mix. Results highlighted that the substitution of cereal silages with an additional share of animal slurry entails an environmental improvement respect to the BASELINE scenario. Considering the displacement of land use towards the cultivation of cereals for feeding, the contraction of import contributes to an improvement of environmental impacts. The higher nitrogen efficiency of the digestate could also reduce the volume of supplemental fertilisers for crops cultivation. Moreover, slurry storage at farm in traditional open tanks causes an increase in Greenhouse Gas Emissions (GHG) due to emissions to the atmosphere. The achieved results support the decision of policy makers to drive the future towards a more sustainable energetic production.

The interest in renewable energy sources has gained great importance in Europe due to the need to reduce fossil energy consumption and greenhouse gas emissions, as required by the Renewable Energy Directive (RED) of the European Parliament. The production of energy from energy crops appears to be consistent with RED. The environmental impact related to this kind of energy primarily originates fromcrop cultivation. This research aimed to evaluate the environmental impact of different crop systems for biomass production: single and double crop. The environmental performances of maize and maize plus wheat were assessed from a life cycle perspective. Two alternative scenarios considering different yields, crop management, and climatic conditions, were also addressed. One normal cubic metre of potentialmethanewas chosen as a functional unit.Methane potential production data were obtained through lab experimental tests. For both of the crop systems, the factors that have the greatest influence on the overall environmental burden are: fertilizer emissions, diesel fuel emissions, diesel fuel production, and pesticide production. Notwithstanding the greater level of methane potential production, the double crop system appears to have the worse environmental performance with respect to its single crop counterpart. This result is due to the bigger quantity of inputs needed for the double crop system. Therefore, the greater amount of biomass (silage) obtained through the double crop system is less than proportional to the environmental burden that results from the bigger quantity of inputs requested for double crop.

Intensive pig farming is responsible for significant air pollutant emissions. This study explores the effect that the large-scale implementation of air cleaning technologies (wet acid scrubbers) for pig housing facilities could have in the European Union. Emissions related to the housing stage of NH3, PM10, NMVOC and indirect N2O from large pig farms (>1000 heads of sows or fattening pigs) are first estimated in the actual situation (current scenario - CS), considering implementation rates and removal efficiencies of the different emission abatement techniques available. Subsequently, alternative scenarios (AS1 and AS2) are simulated with a growing implementation rate of the wet acid scrubber (35% and 65% of the concerned pig farms in all Member States). A comparison between the scenarios was carried out, taking into account emissions reduction, consumables for scrubber operation and environmental credit given by the avoidance of synthetic nitrogen fertilizer production. The annual impact on human health of 21,212 disability-adjusted life years (DALY) in CS was significantly reduced in AS1 (-15%) and in AS2 (-40%), showing that the environmental trade-off given by the consumables is largely overwhelmed by emission abatement. At the same time, the current environmental cost to society of the concerned emissions was estimated at 4154 million € per year (of which 89% due to NH3), which also was reduced in alternative scenarios (−668 and −1765 million € for AS1 and AS2). The abatement of NH3, on which the wet acid scrubber expresses the greatest removal efficiency, was fundamental in both reducing the human health impact and environmental costs, demonstrating the key environmental role of this pollutant and the growing need to find solutions for its containment in the EU.