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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]

Abstract The building's balance point temperature represents the outdoor temperature at which no auxiliary energy is needed to ensure thermal comfort. Its estimation presents the main challenge of applying the degree day method for space cooling applications, since in addition to building thermal characteristics it also depends on internal and external heat gains. In this paper, a new approach for determining the instantaneous balance point temperature, based on an optimization-based grey-box modelling procedure, is presented. The developed grey-box model is built on an assumed functional dependency between the building thermal load and the power demand of its HVAC system. Its application requires only the use of basic building geometric parameters apart from the cooling electricity demand and corresponding meteorological data, which are utilized to estimate the model parameters using a derivate-free optimization procedure. Additionally, a new technique for visualizing and analyzing the behavior of the obtained instantaneous balance point temperature is introduced. The proposed methodology is verified on a set of artificially generated data, achieving an average prediction error of 5.2%, and its applicability demonstrated on a sample of real tertiary sector buildings. The results indicate that the presented methodology can be used to deduce building and corresponding HVAC system characteristics. Highlights • An approach for determining the instantaneous balance point temperature is proposed. • The approach is based on an optimization-based grey-box modelling procedure. • The approach is verified on artificial data and tested on data from real buildings. • A visualization technique for analysing the balance point temperature is introduced. [ABSTRACT FROM AUTHOR]

Abstract Lower heating demands for space heating impose new requirements for the operation of radiators. Contemporary type of new building construction, retrofitted buildings with smaller heat losses and higher requirements for energy efficiency and thermal comfort, demand an improved radiator design and regulation of heat output. As heating systems mostly operate at part loads, it is important to adopt the heat output as quickly as possible to the variable conditions. This paper presents an experimental validation of an improved heat output regulation concept for multi-panel radiators. A novel concept of water flow arrangement for double panel radiators was investigated. The proposed design enables different sequential water flows through each parallel connected panel. The experimental analysis was carried out in two steps: first, the heat output was studied in a nominal steady state at standard testing conditions; second, the radiator was tested at transient conditions. The results show that the implementation of the modified water flow arrangement significantly improves the transient response of heating radiators in terms of reduced time delay and balancing time. An improvement of the regulation ability, expressed as controllability, was also identified. Highlights • Parallel connected panel radiator with sequential water flow arrangement was tested. • Analysis of step heating up process by transient infrared thermography. • Transient response improvement in terms of reduced time delay and balancing time. • Novel regulation concept significantly improves the controllability of heating radiators. [ABSTRACT FROM AUTHOR]

Actual national and international energy strategies generally encourage the use of renewable energy sources. Thermal energy storage (TES) offers various opportunities in the design of renewable energy systems. Thermochemical heat storage has gained popularity among researches because of higher energy density and lower heat loss compared to sensible and latent heat storage. On the other side solar energy has been recognized as one of the renewable energy sources with the most potential. This paper reviews thermochemical heat storage technologies and systems with emphasis on systems involving solar energy utilization in buildings. The studies are reviewed based on used storage materials, system configuration as well as models to predict and optimize system performance. [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]

Abstract: The cooling degree days concept is a tool to estimate and analyze weather related energy consumption in buildings, i.e. the cooling system electric energy consumption. The main problem with applying this method is that it disregards latent cooling loads. This paper deals with an approach for monitoring electric energy consumption due to cooling in buildings based on cooling degree days, which allows an estimation of latent loads. In addition to applying methods for determining base temperature to base humidity, a new technique is introduced, which is based on a significance test of the enthalpy latent days partial regression coefficient. Analogous to the performance line concept, the influence of latent loads can be presented in the form of a “performance surface” graph. The performance surface is a plot of electric energy consumption as a function of cooling degree days and latent enthalpy days. The above methods are tested on data sets consisting of electric energy consumption data obtained from two buildings and hourly meteorological data. [Copyright &y& Elsevier]

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]

Highlights • Influence of temperature fluctuations was examined in a human subjective experiment. • Generated airflows had distinct cooling effect on subjects. • Study indicates that sensation of draught was influenced by airflow temperature fluctuations. Abstract Besides air velocity, turbulence intensity and air temperature there are also other factors, which influence human thermal response to air movement. In this study, the impact of temperature fluctuations in airflow on human thermal sensation and perception of draught was examined. For the purposes of the study an air supply 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. At high values of frequency and amplitude fluctuations a large discrepancy was found between predicted and measured values of draught discomfort. [ABSTRACT FROM AUTHOR]