Annarita Ferrante

Zero- and low-energy housing for the Mediterranean climate

The concept of zero-energy building (ZEB) has gained much international attention and now represents the main future target for the design of buildings. ZEB development in building design construction practice needs to respond quickly to the mandatory new requirements for any new constructions in a few years. This chapter presents and discusses some progress in low- and zero-energy research and practice, with specific reference to the case of the Mediterranean context. It reports the following: a review of the current policy background; some notes on the definition of low- and zero-energy buildings; case studies and demonstration projects; an outlined description of the Mediterranean climate and its cooling demand; passive strategies to reduce the energy demands of buildings; past and ongoing research studies and projects in the Mediterranean region. Starting from very recent research studies in the literature and achievements in building pilot projects, a brief discussion to widen and consolidate current technical knowledge about ZEB and its deep penetration into building common practices is finally presented.

Technologies and Socio-economic Strategies to nZEB in the Building Stock of the Mediterranean Area

The greatest potential for energy savings in the EU is in its existing buildings. The concept of “Nearly Zero Energy Building” (nZEB), which represents the main future target for the design of new buildings, is now gaining increasing attention in relation to the renovation of existing buildings as well. This is exceptionally challenging, considering the economic crisis in the EU and, in particular, in the Mediterranean areas, which are currently experiencing high levels of unemployment, poverty, and social exclusion. This chapter presents and discusses some progress in low- and zero-energy research and practice. It contains a brief review of the current policy background and case studies, and a set of demonstration projects containing evaluation and demonstration procedures that consider the technical, economic, and social feasibility of nearly zero energy buildings in the Athens metropolitan area (AMA).

La strategia del progetto ABRACADABRA per azzerare il consumo energetico e bilanciare i costi nella riqualificazione degli edifici esistenti

La sfida energetica dell’Europa 2020 riguarda principalmente la riqualificazione energetica il patrimonio costruito. Contrariamente alle previsioni e agli indirizzi dettati dal BPIE che indicano al 4% il livello target di riqualificazioni annuali, ad oggi, ogni anno, solo il 1,2% degli edifici esistenti in Europa viene rinnovato. Il rinnovamento del parco edilizio esistente, con l’obiettivo NZEB, e difatti frenato dalle risorse economiche necessarie per procedere a tali adeguamenti, che presentano un alto livello di rischio finanziario e di investimento iniziale e lunghi tempi di rientro della spesa. Sviluppare azioni concertate e innovative, colmare il divario degli investimenti richiesti per l’efficienza energetica e contribuire al rilancio del mercato delle costruzioni e alla creazione di nuovi posti di lavoro, sono le sfide da affrontare per la riqualificazione del patrimonio esistente. Il progetto ABRACADABRA (Assistant Buildings’ addition to Retrofit, Adopt, Cure And Develop the Actual Buildings up to zero energy, Activating a market for deep renovation) mira a identificare le possibili soluzioni tecnico-economiche per ottenere un sostanziale incremento del valore immobiliare attraverso la trasformazione energetica e architettonica degli edifici esistenti. L’articolo illustra i benefici dell’approccio basato sulla strategia delle addizioni volumetriche come soluzione in grado di ridurre consistentemente i tempi di ritorno degli investimenti, e incrementare la qualita abitativa attraverso la sinergia tra nuovo intervento e pre-esistente. In questo contesto, il progetto mira a promuovere un cambiamento paradigmatico che investe anche il settore normativo e procedurale allo scopo di accelerare l’adozione di strategie non convenzionali e non esclusivamente “energy-related” nell’obiettivo di energia quasi zero negli edifici esistenti. Viene presentato lo studio di fattibilita condotto su diversi casi di studio sui quali sono applicate e analizzate diverse soluzioni: dalla ristrutturazione di tipo standard a vari scenari di intervento incrementale. Tutte le soluzioni vengono analizzate e confrontate in termini di risparmio energetico e costo-beneficio.

Understanding Economic Constraints to Achieve Nearly ZEUS

This chapter is concerned with understanding and estimating the economic feasibility of retrofitting actions to achieve nearly zero urban settings (ZEUS). By discussing and comparing the economic and energy impact of different design and architectural options, this chapter aims to address the following important questions: • Is the technical feasibility combinable with the economic feasibility in the retrofitting of existing buildings toward ZEUS?

The Framework of Urban Built Environments

This chapter is concerned with the framework of urban built environments and related energy issues; it discusses some progress in nearly zero energy research and practice, with particular reference to the Mediterranean context and the Athens metropolitan area. This chapter gives a review of the main energy-related issues in an urban environment, with a particular reference to a background description of the Mediterranean climate and its cooling demand related to the heat island phenomenon; a brief review of the current policy background related to nearly zero energy buildings (nZEBs) with some notes on the definition of nZEBs with regard to recent European directives; and a concise review on past and recent case studies and demonstration projects in the Mediterranean region. Starting from these studies in literature and from achievements in pilot projects aimed at reducing the cooling and heating demand in these buildings, a brief discussion to consolidate current technical knowledge in nZEB and its deeper penetration in common building practices is presented. The final section of the chapter also presents the next steps that must be undertaken to widen the nZEB technical knowledge in the existing built environments of Mediterranean cities and to shift the application of today’s technical achievements from being used not only in newly conceived buildings, but also toward the rehabilitation of existing building stock.

Nearly Zero Energy Urban Settings (ZEUS)

The chapter deals with the selection, the study, and the energy analysis developed in three urban settings of the Athens metropolitan area. It opens by proposing a critical discussion concerning the appropriate selection of representative case studies as potential reiterative units in the framework of a whole-city scale. In the three selected real urban environments (RUEs), performed simulations resulted in extremely low energy performance of the existing compound’s buildings as built; therefore, alternative retrofitting design scenarios have been proposed and validated to verify the energy-saving potential of selected techniques at the building scale. Accordingly, the energy generation to set to zero energy the urban settings is also presented.

Integrated Design Strategies For Envelope Skins: User-driven Adaptive Design Solutions To Improve Sustainability And Energy Efficiency In Social Housing

Upgrading the environmental and energy performance of existing buildings has taken in recent years a central role in the issues related to sustainability and energy saving. More than 75% of the energy consumed for heating and air-conditioning is essentially wasted due to inefficient insulation wrap, poor sealing of windows and poor performances of the plants’ system. The identification of the most appropriate retrofitting options is a topic of outstanding importance given the potential costs and impacts involved. To ensure replicable results across the EU context, the research methodology presented in this paper is based on the assumption that the solution has to be found in a multi-disciplinary process applicable to almost all the possible scenarios. Standardized interventions are not the effective and sustainable solutions that we are looking for, pre-made receipts are generally addressed towards one main issue are partly effective and not efficient considering the life cycle of the building. The aim is to combine technologies and design tools in one integrated process: 1) Offering an interesting payback time. 2) Increasing the energy performances of the envelope through variable solutions which increase the participation of the users. 3) Overcoming the existing socio-economic barriers