LCA applicata alle tecnologie alimentate da energia solare: peculiarità e limiti metodologici

La Life Cycle Assessment (LCA) rappresenta una metodologia valida ed affidabile per la valutazione degli impatti energetico-ambientali connessi al ciclo di vita delle tecnologie alimentate da fonti rinnovabili di energia. Il lavoro di seguito presentato focalizza l’attenzione sui sistemi alimentati da energia solare. Gli autori, dopo un’analisi degli studi di letteratura inerenti la LCA applicata ai sistemi solari termici e fotovoltaici, descrivono le principali questioni metodologiche connesse alla valutazione delle prestazioni energetico-ambientali di tali tecnologie

Life-cycle optimization of building performance: a collection of case studies

The building sector is one of the most impacting on the energy demand and on the environment in developed countries, together with industry and transports. The European Union introduced the topic of nearly zero-energy building (nZEB) and promoted a deep renovations in the existing building stock with the aim of reducing the energy consumption and environmental impacts of the building sector. The design of a nZEB, and in general of a low-energy building, involves different aspects like the economic cost, the comfort indoor, the energy consumption, the life cycle environmental impacts, the different points of view of policy makers, investors and inhabitants. Thus, the adoption of a multicriteria approach is often required in the design process to manage some potential conflicting domains. In detail, one of the most suitable approaches is to integrate the preliminary building design (or renovation) phase in a multi-objective optimization problem, allowing to rapidly compare many alternatives and to identify the most adapt interventions

L'applicazione della Direttiva ErP presso le piccole e medie imprese: punti di forza e criticità

La Direttiva ErP sulla progettazione ecocompatibile dei prodotti connessi all’energia richiede che le imprese applichino dei criteri di eco-design orientati alla riduzione degli impatti energetico-ambientali lungo tutte le fasi del ciclo di vita dei loro prodotti. In tale contesto la Life Cycle Assessment (LCA) rappresenta uno strumento di fondamentale importanza per individuare le “key issues” energetico-ambientali connesse ai processi produttivi. L’articolo presenta i risultati di una LCA applicata ad una caldaia a biomassa prodotta in Sicilia, evidenziando i punti di forza e le criticità connessi all’attuazione della Direttiva da parte delle piccole e medie imprese

Life Cycle Environmental Assessment of Energy Valorization of the Residual Agro-Food Industry

This study assesses the potential environmental impacts related to the energy valorization of agro-food industry waste thought the Life Cycle Assessment methodology (ISO 14040). The system examined consists of a real anaerobic digester coupled with a combined anaerobic digester and heat and power plant (AD-CHP) operating in Sicily. The analysis accounts for all the impacts occurring from the delivery of the biomass to the AD-CHP plant up to the electricity generation in the CHP. The main outcomes of the study include the eco-profile of the energy system providing electricity and the assessment of the contribution of each life cycle phase aimed at identifying the potential improvement area. The obtained results highlight that the direct emissions associated with the biogas combustion process in the CHP account for 66% of the impact on climate change, and feedstock transport contributes 64% to the impact on mineral, fossil fuels, and renewable depletion. The contribution to the impacts caused by the electricity consumption is relevant in many of the environmental categories examined. It ranges from a minimum of about 22% for climate change up to 82% for freshwater ecotoxicity. Then actions aimed at reducing electricity consumption can significantly improve the environmental performances of the energy system examined

The use of Genetic Algorithms to solve the allocation problems in the Life Cycle Assessment

The paper applies a GA (Genetic Algorithms) to a multi-output productive process of essential oils, natural and concen-trated juices from oranges and lemonsThe results obtained for the case study taken into consideration showed that the application of GA allows to respect the energ y and mass balances for the examined system

Life cycle assessment of a solar PV/T concentrator system

The paper shows the energy and environmental analysis of a solar low Concentrating Photovoltaic-Thermal (CPVT) system, installed on the roof of the Energy Department building at University of Palermo (Italy). LCA methodology was applied to assess the whole life-cycle of the selected Functional Unit. Data survey from the producing company regarding the consumption of energy sources and of materials were developed. The assessment allowed to identify the steps and the system components addressing the highest energy and environmental impacts. Energy and environmental benefits and drawbacks related to the CPVT system. The research was developed within the National Relevant Research Programme (PRIN 2008) ‘‘Definition of innovative criteria for the environmental oriented design and production of Energy Using Products in the civil sector”

Design di edifici a energia netta zero alla luce della Direttiva Europea 2010/31/CE (EPBD recast) sulla prestazione energetica nell'edilizia [GU europea del 18 giugno 2010 (L 153)]

Il presente lavoro descrive dettagliatamente gli studi e le attività svolte in seno al progetto di ricerca “Design di edifici a energia netta zero alla luce della direttiva europea 2010/31/CE (EPBD Recast) sulla prestazione energetica nell’edilizia GU Europea del 18 giugno 2010 (L153)”. L’attività di approfondimento sull’edificio oggetto di studio, la Leaf House, è stata svolta nell’ambito dei diversi filoni di ricerca di seguito elencati: 1. Analisi dei dati dell’edificio esistente, 2. Redesign dell’edificio esistente, 3. Embodied energy dell’edificio esistente. 4. Partecipazione a gruppi di lavoro internazionali in seno alla task 40 dell’IEA. Gli indicatori sviluppati nel corso dei lavori della Task 40 sono stati applicati al caso studio Leaf House, dimostrandone l’efficacia nell’identificare e descrivere il problema del mismatch. L’approfondimento nell’ambito del redesign dell’edificio ha permesso di stimare dei consistenti risparmi di energia elettrica qualora le soluzioni impiantistiche e tecnologiche venissero implementate. L’analisi LCA ha consentito di stimare l’embodied Energy del sistema edificio-impianto. Saranno presentati nel seguito i risultati di ogni filone di ricerca e le attività svolte e in corso di svolgimento nell’ambito della collaborazione con la task 40 dell’IEA

Investigating energy saving potential in a big shopping center through ventilation control

This paper investigates energy saving measures for the ventilation system of large shopping centers. This kind of buildings is characterized by high yearly energy consumptions, because of the high level of operating hours and the frequent use of obsolete technologies. In the analyzed case studies, three big Do It Yourself (DIY) shops, located in Italy, are considered. Two different approaches are considered, they are aimed at reducing the annual energy consumption for the indoor air exchange of the sales area. The first considered retrofit solution consists in the installation of heat recovery exchangers, reducing the energy demand for the air thermal treatment without changing the airflow value. In the second scenario, smart air quality sensors are inputs for the modulation of the air exchange rate according to the actual requirement for indoor air quality. In a third scenario, the application of both retrofit solutions is considered. For each scenario, the paper reports the yearly energy savings, the avoided CO2 emissions and cost saving indicators. Furthermore, as the three shops are equipped with different heating systems and are located in different parts of Italy, a technological and climatic comparison is provided

Selecting Insulating Materials for Building Envelope: A Life Cycle Approach

This paper aims at assessing the embodied energy and greenhouse gas emissions (GHGs) of two building envelopes, designed for a two floors semi-detached house located in the Central Italy. The analysis is performed by applying the Life Cycle Assessment methodology, following a from cradle-to-gate approach. Fixtures (windows and doors), external and internal opaque walls, roof and floors (including interstorey floors) make the building envelopes. Their stratigraphy allows for achieving the thermal transmittance values established in the Italian Decree on energy performance of buildings. The two examined envelopes differ only for the insulation material: extruded expanded polystyrene (XPS) or cellulose fibers. The results shows that the envelope using cellulose fibers has better performance than that using XPS: it allows for reducing the embodied energy and the GHGs of about 13% and 9.3%, respectively. A dominance analysis allows to identify the envelope components responsible of the higher impacts and the contribution of the insulating material to the impacts. The study is part of the Italian research “Analysis of the energy impacts and greenhouse gas emissions of technologies and components for the energy efficiency of buildings from a life cycle perspective” funded by the Three-year Research Plan within the National Electricity System 2019-2021