Influence of insulating materials on green building rating system results

This paper analyzes the impact of a change in the thermal insulating material on both the energy and environmental performance of a building, evaluated through two different green building assessment methods: Leadership in Energy and Environmental Design (LEED) and Istituto per l'innovazione e Trasparenza degli Appalti e la Compatibilità Ambientale (ITACA). LEED is one of the most qualified rating systems at an international level; it assesses building sustainability thanks to a point-based system where credits are divided into six different categories. One of these is fully related to building materials. The ITACA procedure derives from the international evaluation system Sustainable Building Tool (SBTool), modified according to the Italian context. In the region of Umbria, ITACA certification is composed of 20 technical sheets, which are classified into five macro-areas. The analysis was developed on a residential building located in the central Italy. It was built taking into account the principles of sustainability as far as both structural and technical solutions are concerned. In order to evaluate the influence of thermal insulating material, different configurations of the envelope were considered, replacing the original material (glass wool) with a synthetic one (expanded polystyrene, EPS) and two natural materials (wood fiber and kenaf). The study aims to highlight how the materials characteristics can affect building energy and environmental performance and to point out the different approaches of the analyzed protocols

Computational Fluid Dynamic Modelling of Thermal Periodic Stabilized Regime in Passive Buildings

The periodic stabilized regime is the condition where the temperature of each point of a certain environment varies following a periodic law. This phenomenon occurs in many practical applications, such as passive or ancient buildings not equipped with Heating, Ventilating and Air Conditioning HVAC systems and located in latitudes where the temperature greatly varies with Earth's daily cycles. Despite that, the study of transient phenomena is often simplified, i.e., considering negligible the thermal response of the indoor microclimate. An exact solution to enclosures whose microclimate is free to evolve under a periodic stabilized regime does not exist nowadays, also from an analytical point of view. The aim of this study is to parametrically analyze the thermal variations inside a room when a transient periodic temperature is applied on one side. The phenomenon has been numerically studied through Computational Fluid Dynamics (CFD) and analytically validated using a function that reproduces the daily variation of the outdoor temperature. The results of this research would lay the groundwork to develop analytical correlations to solve and predict the thermal behavior of environments subject to a periodic stabilized regime

Lighting Design for Plant Growth and Human Comfort

Plants have several positive effects on humans validating their use in interior spaces. In addition to their pleasantness, the enhancement of human psychological wellbeing and the improvement of environmental parameters are two favourable aspects. Light is a vital element, used by plants for photosynthesis and morphogenesis and by human being for vision and for the regulation of the circadian rhythms, but they need different lighting conditions in quantity as well as in quality. Usually the human-being oriented lighting design for interiors only guarantees the survival of plants as it is inadequate for their proper growth and development. The aim of this paper is to develop an approach to interior lighting design suitable both for humans and plants in terms of quality of light and physiological requirements. The hall of a museum was introduced as a virtual experimental setting, testing the positive impact of new lighting technologies

The impact of spectral composition of white LEDs on spinach (Spinacia oleracea) growth and development

Light-emitting diodes (LED) are a promising light source for the cultivation of edible vegetables in greenhouses. The spectral radiation of the light sources has an impact on plants physiological parameters, as well as on morphological features. In this study the growth of spinach plants has been carried out in experimental boxes under two white LED treatments having different correlate color temperature (CCT): the cold lighting (CL) corresponded to 6500 K, while the warm lighting (WL) to 3000 K. The work was aimed to investigate the influence of the two light spectra on plant development and comparing the results. Results showed that the different lighting treatments impact differently on plant development and on growth parameters

A multilevel method to assess and design the renovation and integration of Smart Cities

Contemporary cities are the scenes of sudden and numerous changes from social, economical and environmental points of view. The capability for cities to endorse, foster, enhance ongoing transformations and modern challenges is obstructed by the unsuitableness and lack of communication and integration of both material and immaterial infrastructures. The new vision of Smart Cities can fill these gaps, as it represents a balance among hardware and software aspects, technology and human capital, and it aims at realizing and guaranteeing the quality of life to the inhabitants. At today, there is absence of uniformity both in the definition and in the concept development of a Smart City, and there are not practical methodologies supporting the evaluation models developed in literature. The approach often does not appear as a holistic, complete and integrated, but as a combination of sector-based non communicating and non integrated actions. In this framework, the aim of this paper is to outline a planning methodology of actions to realize a Smart City that provides a holistic and specific approach to territories and cities by taking into account the specific features of the context and by developing different and appropriate strategies. According to this, a way to integrate the various aspects of a Smart City through the definition of the relations existing among all the subsystems of the city, considered as a whole (human) organism, has been developed. © 2014 Elsevier Ltd. All rights reserved

On the thermal response of buildings under the synergic effect of heat waves and urban heat island

Global and local climate change increases the occurrence and the magnitude of extreme phenomena, as urban heat island and heat waves. These phenomena seriously affect the quality of life in several aspects: society, health, environment; they also heavily affect the building sector, increasing the energy use for cooling and deteriorating the indoor thermal environment. This paper utilizes data from a continuous urban microclimatic monitoring over three years to quantify the impact of heat waves on the thermal quality of two reference residential buildings in the city of Rome, Italy. The synergic effect of heat waves with the urban heat island is also analysed. The observation period includes summers of 2015, 2016 and 2017. The buildings’ response is analysed through numerical thermal analyses in transient regime, taking into account several variants: thermal insulation, mechanical cooling system and thermal free-floating conditions, with different night ventilation strategies. Results show that daily average temperature and urban heat island intensity increase by up to 4.3 ◦C and 1.5 ◦C respectively during the heat waves with respect to the rest of the summer. The building cooling energy use rises up 87% during heat wave periods, while average operative temperature in free-running buildings increments by up to 3.5 ◦C. Results also show the impressive combined impact of heat wave and heat island: triplication of cooling energy use in the worst case and increase of the average operative temperature above 5 ◦

The pedestrian's perspective: How do illuminance variations affect reassurance?

The Economist Intelligence Unit Safe Cities Index summarizes the primary issues of Safety as being digital security, health security, infrastructure safety and personal safety. The biggest challenge for cities is to identify all the issues that actually impact on public safety and comprehend the real perceptions - or misconceptions - that citizens may have. Reassurance describes the confidence a pedestrian might gain from road lighting (and other factors) to walk along a footpath or road after dark, and is intended to describe both perceived safety and fear of crime. Past studies have demonstrated that the presence, level and quality of lighting affect human perception of safety. This article describes a field survey of reassurance carried out in Rome to investigate methods for measuring how changes in illuminance affect reassurance. These results confirm that the reassurance of participants can be put in relation with street lighting since changes in illuminance levels were highly perceived by test participants. It was also found that reassurance is more related to the mean horizontal illuminance than to the minimum illuminance or minimum/average uniformity