Preparation and thermal properties of mineral-supported polyethylene glycol as form-stable composite phase change materials (CPCMs) used in asphalt pavements

Tis work was supported by the National Natural Science Foundation of China (51704040, 51778071, 51608058), the Scientifc Research Project of Hunan Provincial Department of Education for Excellent Young Scholars (16B007), Open Fund of Key Laboratory of Special Environment Road Engineering of Hunan Province (Changsha University of Science & Technology, kf160501), and Open Fund of Key Laboratory of Biohydrometallurgy, Ministry of Education (Central South University, MOEKLB1708)

Occupant productivity and office indoor environment quality : a review of the literature

The purpose of this paper is to review the existing literature to draw an understanding of the relationship between indoor environmental quality and occupant productivity in an office environment. The study reviews over 300 papers from 67 journals, conference articles and books focusing on indoor environment, occupant comfort, productivity and green buildings. It limits its focus to the physical aspects of an office environment. The literature outlines eight Indoor Environmental Quality (IEQ) factors that influence occupant productivity in an office environment. It also discusses different physical parameters under each of the IEQ factors. It proposes a conceptual model of different factors affecting occupant productivity. The study also presents a review of the data collection methods utilised by the research studies that aim to investigate the relationship between IEQ and occupant productivity. The study presents a comprehensive discussion and analysis of different IEQ factors that affect occupant productivity. The paper provides a concise starting point for future researchers interested in the area of indoor environmental quality

Passive cooling of outdoor urban spaces. The role of materials

This paper presents the results of a comparative study aiming to investigate the suitability of materials used in outdoor urban spaces in order to contribute to lower ambient temperatures and fight heat island effect. The study involved in total 93 commonly used pavement materials outdoors and was performed during the whole summer period of 2001. The thermal performance of the materials was measured in detail using mainly infrared thermography procedures. The collected data have been extensively analysed using statistical techniques. Comparative studies have been performed in order to identify the major advantages and disadvantages of the materials studied. Materials have been classified according to their thermal performance and physical properties into ‘cool’ and ‘warm’ materials. The impact of color, surface roughness and sizing has been analysed as well. The study can contribute to selection of more appropriate materials for outdoor urban applications, and thus assist to fight the heat island effect, decrease the electricity consumption of buildings and improve outdoor thermal comfort conditions. (C) 2004 Elsevier Ltd. All rights reserved

Quantifying energy savings in daylight responsive systems: The role of dimming electronic ballasts

The application of lighting control technologies with photosensors has led to an increase in public interest. Although these technologies have been promoted during the last years their successful use in buildings has been accomplished in a small percentage of new projects. One reason is the difficulty in quantifying the energy savings and thus the subsequent payback period. Daylight responsive dimming systems consist of three basic components: photosensor, controller, and dimming unit. Electronic dimming ballast (EDB) is one substantial component of these lighting control systems which can adjust the light output due to the transferred signal from the photosensor and lighting controller. The aim of this study is to quantify energy savings among different EDBs. Eighteen commercial EDBs were selected and various sets of electrical and illuminance measurements were taken for different dimming levels, in order to develop polynomial functions between light output and consumed power. Using the measured data, a set of simulations were performed for a photosensor with an ideal cosine spatial sensitivity distribution installed in a typical office room using two control algorithms, closed loop and integral reset, trying to quantify the relative differences in energy savings. (c) 2007 Elsevier B.V. All fights reserved

The environmental impact of the new version of the Interior Lighting European Norm in Lighting and Circadian Design

Abstract The new version of the European Standard of Interior Lighting (EN 12464-1) considers LED technology for energy saving and minimizing environmental impact by giving new criteria for quantitative and qualitative lighting, including those that concern the “non-image-forming effects” (NIF) of light. In addition, it takes into account normal aging as an assumption for proposing increased light levels in indoor workplaces. In real applications, this seems to create lighting conditions that do not fully support human well-being based on the criterion of WELL Building Standard v2 (2021) for Circadian Lighting Design. Therefore, in offices, it is proposed to increase the light levels by at least one step from the minimum provided by the EN Standard. In order to examine this hypothesis, a typical office space is examined. In addition to the main requirements, the Mean Ambient Illuminance (Ēamb) and the Mean Room Surface Luminous Exitance (Mrs) are calculated according to the EN Standard but also the Equivalent Melanopic Lux (EML) and the Melanopic Equivalent Daylight Illuminance (M-EDI) as proposed by the WELL Standard. The comparison between EN 12464-1 and Well Standard has shown that the qualitative lighting design criteria are stricter in WELL than in EN Standard.</jats:p

Performance assessment of an active sunlight redirection system in areas with different climate: A comparison

The aim of this work is to assess the impacts, both in terms of daylight efficiency and energy impacts, of an advanced daylighting system that utilizes a heliostatic configuration for sunlight redirection in a deep South oriented office room in two (2) different climate conditions. Conventional daylighting systems such as windows, and clerestories placed on building facades, for a variety of reasons, have been proven ineffective in solving the problem of deep interior daylighting. This effect even with the use of modern daylighting techniques can effectively maintain the required illuminances. In such cases, systems that are designed to take advantage both the direct and diffuse natural light while maintaining and improving occupant visual comfort, particularly at greater distances from the external walls can provide higher work-plane illuminance levels deeper into the space. The results summarized here demonstrate that, if selected according to daylight climate and integrated appropriately with electric lighting controls, the system can enhance daylight in building interiors and thereby promote energy savings. It should be noted, however, that the performance of these systems is dependent on daylight availability. Nonetheless, the information presented in this paper demonstrates the potential benefits and shortcomings from the use of sunlighting technologies in different climate zones. © 2020 Published under licence by IOP Publishing Ltd