National survey on ventilation system and occupants’ health in japan

The indoor environment and occupants’ health of approximately 5,000 residential buildings were investigated by a questionnaire covering entire Japan. The purpose of this survey is to clarify the association between indoor air pollution and adverse health effect, and to study effective ways of keeping indoor air clear with ventilation systems in house. Questionnaires were distributed to 7,812 occupants living in a house with a mechanical ventilation system across 47 Prefectures in Japan on February 2012 using internet survey web site.

A holistic approach of the development and application of innovative composite cool-thermal insulating materials

The need to improve the energy performance of buildings, both new but also, and in particular, existing ones, is more imperative than ever. The “traditional” approach of thermal insulation is quite satisfactory for the reduction of thermal heating losses and loads, but it is not enough for coping with the problem of increased cooling loads, that are evolving to the single most influential problem, mainly for buildings in the densely built urban environment in Mediterranean and Southern European countries. 

On the analysis of cool roofs for cooling system efficiency

Cool roof is a well-documented passive cooling strategy for buildings in several climate conditions. The mechanism consists of the reduction of the heat load entering the roof, which is characterized by high solar reflectance and high thermal emittance. The purpose of this paper is to study the coupled effect produced by such a technology. First, the passive cooling contribution is quantified, then, the “active” contribution is investigated.

Performance of self-cleaning cool cementitious surface

A strategy to reduce global warming is to increase the reflectance and thermal emittance of the built environment (Akbari, Menon, e Rosenfeld 2008). The urban heat islands usually increase the temperature by more than 10ºC (Santamouris et al. 2001).  A cool roof can reduce the temperature up to 3.3ºC (Synnefa, Santamouris, e Akbari 2007) and improve indoor thermal comfort and reduce energy consumption.

Influence of the irradiance spectrum on solar reflectance measurements

Solar reflectance is the key performance parameter of cool roof and cool pavement materials. For its assessment, the measured spectral reflectivity of the sample is weighted by a reference spectrum of solar irradiance. Several standard and non-standard spectra are however available, taking into account different climate conditions, angle of incidence of the solar beam, contribution of the diffuse radiation content.  

Considering the Attica exampleː hotel location as a determinant factor of tourist carbon footprint

The tourism industry is responding to the widespread concern over the future of the global climate. However, little quantitative work has been done on carbon dioxide emissions associated with tourism destinations. This paper proposes a framework illustrating how this can be done. The tourist carbon footprint (TCF) is a result of tourists’ personal consumption, transportation, activity, and accommodation costs. In this study we evaluate the tourist carbon footprint associated with tourist transportation to and in the vicinity of the prefecture of Attica, Greece.

Toward designing strategies for urban heat island mitigation based on multiscale flow considerations

Much of the on-going discussion on urban heat island mitigation and proposed measures for cooling is based on case-studies taken at a specific scale and settings; the evaluation of the effectiveness of proposed cooling measures is therefore made using performance criteria derived for that specific scenario.  The transferability of this knowledge to other sites and climatologies is not ensured.

Development of self-cleaning top-coat for cool roof

Our recent study has shown that the acrylic silicon polymer is useful to formulate self-cleaning topcoat which may maintain the thermal insulation effect of cool roof effectively. 
A 2K self-cleaning topcoat was formulated with a water-borne type acrylic silicon polymer. Its effect to maintain high solar reflectance was confirmed by outdoor exposure test in comparison with coatings having no self-cleaning function. The solar reflectance performance was well maintained regardless of installation angle, lightness of colour or pigment type. 

The impact of temperature increase in Greece on the energy demand of buildings

The increase of the ambient air temperatures in urban areas during the past few decades, due to the heat island phenomenon and the warming of the lower atmosphere, has strong impact on the energy profile of buildings, the comfort conditions, the air pollution and the indoor environment, especially in the Mediterranean regions with hot climate conditions. The present paper focuses on the investigation of the impact of the temperature increase in nine Greek cities over the last forty years on the energy demand of buildings.

On investigating instantaneous wind-driven infiltration rates using CO2 decay method

Carbon dioxide has been already recognized as a potential tracer gas towards estimation of the mean air exchange rates (ACH) of a room or building. The wind direction and mean wind velocity have been also clarified as critical factors that affect the air infiltration. In this study, the indoor CO2 concentration is detected and logged at three specific points in an office room for seven selected measurement-periods. The decay method is used to estimate the leakage rates.

Pages