Multi-functional Integrated System for Energy Retrofit of Existing Buildings: A Solution Towards nZEB Standards

The present work is aimed at assessing the energy performances of a multi-functional integrated system designed to cover the HVAC needs using renewable energy sources (RES), with a specific focus on residential buildings. In detail, within the system design, RES are represented by building integrated photovoltaics (BIPV) and aerothermal energy. The heating, cooling and DHW demand is in fact satisfied by a reversible and high efficiency air-water heat pump with continuous power modulation, optimized for the specific purpose, directly fed in direct current (DC) from the PV. The eventual surplus of PV production can be stored in form of thermal energy thanks to a dedicated storage system for providing heating, cooling or DHW production in the periods when there is no/low solar radiation. Moreover, the system is able to minimize the peak power demand of electricity, according to the match between PV electricity generation and usable/storable thermal energy demand. The results of the energy simulations on a case study residential building demonstrate the effectiveness of the proposed system towards nZEB standards

Sustainable Building Design in Kenya

Sustainable design strategies involve complex interactions among social, economic and environmental factors those should be analyzed and solved quite differently by heterogeneous disciplines and stakeholders involved. Focusing on the cities of developing countries in tropical regions, characterized by fast urban population growth and a staggering increase in the energy consumption for building sector, it emerges that appropriate active strategies and building energy optimizations are promptly recommended. For this purpose, in the present work, energy evaluations were carried out for the designing of a residential building in Nairobi, Kenya, considering different strategies and solutions, taking into account also the affordability and considering the possibility to push local based economies through the use of built-on-site materials. This strategy may lead to a significant cost reduction and energy saving due to lower construction costs and in addition also a lower embodied energy of the building materials. Furthermore, in a region understudy, characterized by unstable economic security, the employment of local labor forces may lead to the formation of local based economies

Wet Curtain Wall: A Novel Passive Radiant System for Hot and Dry Climates

This paper proposes a novel radiative passive system for hot and dry climates to improve outdoor thermal comfort. The solution consists in a curtain, characterized by two different finishing surfaces, one is waterproof and the other one is absorbent, immersed in a water tank by means of a mechanized system and subsequently used as a radiant surface with reduced temperature thanks to evaporative cooling effect. The effectiveness of the proposed system is verified by means of CFD simulations carried out on a sample application in outdoor space and supported by experimental measurements carried out on a small sample of curtain. The results showed that the proposed system can reduce the operative temperature up to 6°C with respect to the testing conditions (air temperature of 28.5°C and relative humidity of 50.5%) ensuring higher comfort levels and a limited water consumption to keep the curtain constantly wet (25 l/h for 130m2 of wet curtain)

CFD Comfort Analysis of a Sustainable Solution for Church Heating

Historic building heating and, in particular, church heating represents a challenging task because many objectives have to be reached simultaneously, such as occupants thermal comfort and optimal internal climate suitable for the preservation of fragile building components and artworks. Moreover, current requirements for sustainability impose to make efforts, where possible, to minimize the amount of energy needed and the consequent environmental impact. Innovative solutions are currently under research and development and are mainly based on electric radiant surfaces. The present work represents actually a detailed performance analysis of a novel hydronic high-efficiency pew-based heating system coupled with a ground-source heat pump. The system was specifically developed for the above-described application field, with particular reference to the Basilica di Collemaggio (L'Aquila, Italy), a church of worldwide relevance currently under restoration. In detail, within the work a three-dimensional CFD analysis of the heating solution was carried out considering as application field a virtual test room containing two benches with three virtual sitting manikins. Heat exchanges between the human body surfaces, the room environment and the heated benches were simulated in order to assess the whole performance. The results show that the air temperature in the room is not significantly influenced by the heating system, but the heat is directly radiated to people, ensuring comfortable conditions and contributing to artworks preservation

L’ applicazione pratica di un metodo di RIQUALIFICAZIONE ENERGETICA sviluppato dal Politecnico di Milano: il recupero di ERGO a Milano

Nel 2007, il precoce degrado delle facciate della sede italiana della società assicurativa ERGO ha reso indifferibile un sostanziale rinnovamento dell’involucro. Contemporaneamente si imponeva un sostanziale abbattimento dei consumi energetici, la cui incidenza sui costi di gestione dell’immobile era esorbitante. Il notevole aggravio economico a carico della proprietà è stato letteralmente trasformato in un investimento redditizio, basato sui benefici ed i risparmi conseguibili abbinando ai lavori di ristrutturazione l’applicazione di tecnologie e metodologie d’avanguardia, destinate all’abbattimento dei consumi e delle emissioni correlate