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The influence of dissimilar cooling and ventilation system combinations on indoor environmental quality (IEQ) has been studied. A comparison of chilled ceiling cooling in combination with displacement ventilation, cooling with fan coil unit, and cooling with flat wall displacement inlets was performed. All observed variations were evaluated based on whole-body and local thermal comfort criteria as well as with regard to ventilation effectiveness. The analysis was made based on results of numerical simulations carried out in two steps. First, DesignBuilder was applied to model the buildings’ thermal performance and to evaluate its interaction with the environment. The latter included the calculation of heat gains as well as the heat loss on the boundary surfaces of the observed air-conditioned room. In the second step, ANSYS Fluent was used to simulate the response of indoor environment by utilizing the simulation results obtained in the first step, in order to evaluate the interaction between building and human. Afterwards, the observed thermal comfort and ventilation criteria were merged into a novel indoor environment indicator, which enables to describe the indoor environment quality with a single value. Among the analysed systems, the ceiling cooling system in combination with displacement ventilation was found to be the most suitable as it offers a high level of thermal comfort with adequate ventilation efficiency. Fan coil cooling was the least favourable option in terms of thermal comfort, while flat wall displacement inlets exhibited the lowest ventilation effectiveness. The performed investigation demonstrated the necessity to assess indoor environment with regard to IEQ in addition to energy consumption.

In ventilated and air-conditioned indoor environment, air movement substantially impacts thermal sensation and comfort of occupants from the point of view of whole body and local thermal sensation. Skin temperature and its rate of change are important factors for thermal sensation. Both are affected by the airflow velocity and temperature changes around the body which causes skin temperature fluctuations and changes in convective heat transfer. In this study the impact of temperature fluctuations in airflow on human thermal sensation was examined. For the purposes of the study, an air handling unit was designed for generating airflows with temperature fluctuations and used in a subjective experiment. The experimental study indicates that temperature fluctuations possibly influence the human perception of air movement with a distinct cooling effect.

Residential energy demands are expected to change significantly in the future with increasing electrification, energy efficiency, and improved comfort as well as climate change. While many studies have been performed into how the aforementioned influential factors could affect the energy needs of the forthcoming generations, far less are present for how population aging affects the future heating demand. The latter is particularly relevant for Europe and Slovenia as declining fertility rates and lengthening life spans give rise to the increasing ratio of the elderly. In this paper, the future residential space and water heating energy demands of the aging society in Slovenia, using a sample of geographically dispersed nursing homes as a proxy, are estimated. The results are compared against the latest EU reference scenario until 2050, whereby the adjusted estimates differ by up to 9.6%. Thus, the study highlights the need for energy policy to be further refined and redefined to link the energy performance requirements of buildings to specific consumption characteristics of the elderly. [ABSTRACT FROM AUTHOR]

In cases where a quick insight into the operation of an HVAC system is more important than accuracy, cooling degree days can be used for monitoring electric energy consumption dependent on meteorological conditions. Cooling degree days are calculated from differences between outdoor temperatures above the base temperature and the base temperature itself, therefore containing both climate and building information. The difficulties in applying this method are the determination of base temperature and choosing a procedure for calculating degree days, which vary depending on the resolution of the weather data used. In addition, the cooling degree method has a major flaw, i.e. it considers only a linear dependence between cooling energy consumption and sensible cooling load, thereby ignoring latent loads, which become more significant at higher outdoor temperatures In this article an analysis of real electric energy consumption data using the cooling degree method and an improved method derived from it that includes latent loads, as well as a comparison between them, are shown. Both methods are applied several times to metered data, each time with a different combination of a method for determining base temperature and a degree day calculation technique. [ABSTRACT FROM AUTHOR]

Process industries are the foundation of the European economy, transforming raw materials into building blocks for strategic products and applications in today's society. Such industries range from steel, cement, or minerals to chemicals such as lubricants for wind turbines and polymers that prevent waste in logistic supply chains. The downside of this foundation industry is its high environmental impact regarding emissions, and intensive use of energy and resources. One of the key strategies to address such challenges is industrial symbiosis: various industries establish collective efforts to find value while transitioning to a more circular economy. This paper presents an exploratory analysis of databases on IS case studies. We used the European standard classification for economic activities (NACE) to draw industrial sector profiles for the most relevant energy-intensive industries: chemicals, steel, and cement, coupled with urban synergies. The majority of the synergies includes the chemicals sector with most commonly shared streams being energy, water, and carbon dioxide. IS cases are ranked in terms of frequency, then classified in topical groups and finally, the sustainability impact of the different categories is discussed. The outcome is a methodology to frame and assess industrial symbiosis case collections useful for future exploring and exploiting circularity projects in public and private organisations. • Sectoral profiles for industrial symbiosis with standardised sectors and resource sharing. • Focus on cross-sectoral exchanges in process industry sectors: chemicals, steel, and cement including urban synergies. • Insights on the technology and sustainability gains per shared resource category. • New method to develop continuous improvement in industrial symbiosis databases. [ABSTRACT FROM AUTHOR]