Promoting the decarbonisation of buildings requires effective policy measures. An integral part of policy design is ex-ante evaluation of possible policy options and effects. System Dynamics, one of a range of potential modelling paradigms, emphasises the dynamic complexity arising from stock-and-flow structures, feedbacks, non-linearities and time lags of the system in question. It is therefore well

Frosting and refrigerant distribution uneven easily are two key problems restricting the wide application of micro-channel heat exchanger in the field of air source heat pump (ASHP). In this paper, frosting experiments were carried out on two kinds of micro-channel heat exchanger in three cases that with different refrigerant distribution characteristics. Frost and temperature distribution characteristics

This paper examines the extent to which males and females report different thermostat settings using data from single-occupant homes in the United States. Reported thermostat settings for heating and cooling at night, at home, and when away from home are rigorously tested for behavioral differences between the sexes. In general, single-occupant males and females report the same thermostat settings

Growth of frost layer on cold fins of tube-fin heat exchangers leads to an increase in the pressure drop and a decrease in the frost thermal conductivity and thereby the heat transfer rate. There is a lack of a general model in the literature for estimating the frost thermal conductivity on parallel plate channels, including almost all parameters affecting this factor. In this study, for the first

Variable refrigerant flow (VRF) systems have gained much attention and been widely used in commercial and residential buildings benefitting from their competitive advantages. However, after long-term operation in a complex environment, various faults may occur in the VRF systems, resulting in failure to meet users comfort requirements and even unnecessary increase in energy consumption. This paper

The potential reduction in energy consumption for space heating in buildings realised by the use of predictive control systems directly depends on the prediction accuracy of the building thermal behaviour model. Hence, model calibration methods that allow improved prediction accuracy for specific buildings have received significant scientific interest. An extension of this work is the potential use

Heating, ventilation and air-conditioning (HVAC) systems have been adopted to create comfortable, healthy and safe indoor environments. In the control loop, the technical feature of the human demand-oriented supply can help operate HVAC effectively. Among many technical options, real time monitoring based on feedback signals from end users has been frequently reported as a critical technology to confirm

Building renovation plays a key role in reducing greenhouse gas emissions and achieving the climate protection goals. The district scale approach is one of the most effective approaches to accelerate this process of reducing the energy consumption in the building sector as increasing its renovation rates. In this context, the Energy in Buildings and Communities Programme of the IEA, IEA-EBC started

In the district heating (DH) systems, the thermal storage tank is widely used for domestic hot water (DHW) preparation to shave the peak load. Compared to the space heating, the domestic hot water demand exists for all seasons, and the variation of which is more dramatic within short time span. Therefore, the well-controlled storage tank is of great help to stabilize the district heating operation

This study questions the extent which steady-state calculation methods for the draught rate according to ISO 7730 are applicable to intermittent ventilation, especially with pulse durations shorter than 30 s. 37 subjects were exposed to intermittent ventilation in a cooling scenario at neutral room temperature, i.e. in an ambient that was neither warm nor cool. Two displacement air diffusers supplied

In cities, the tallest rooftops have the best potential for electricity production. They often combine good wind and solar conditions with available space. Rooftop-mounted photovoltaic (PV) panels have already proven their efficiency and profitability. For tall rooftops with good wind conditions, also small wind turbines can be economically viable. However, hybrid PV-wind systems apparently have never

Zero-net-energy (ZNE) homes produce an adequate amount of energy on-site to meet their energy demand based on source energy for an entire year. California building energy efficiency standards require new residential buildings started in 2020 to be ZNE. For various reasons, a home designed as ZNE may not achieve ZNE performance in real operation. This study aimed to quantify the robustness of the energy

The aim of this paper is to gain new knowledge on contributions of energy renovation of multi apartment buildings to economy and climate changes. The research methodology is based on applying the input–output model, which enables the analysis of direct, indirect and induced effects. The analysis was conducted on the sample of the Republic of Croatia. The reference research period is from 2017 to 2020

It has been known that for space heating ASHPs, different operations and configurations can influence their frosting suppression performances. However, the practical applications through varying the operations and configurations of ASHPs for frosting suppression has not been well documented. Therefore, in this paper, field investigations on frosting suppression for variable-capacity ASHPs through optimizing

Despite the endorsement of green building regulations and the incorporation of energy-efficient technologies, commercial buildings often fail to achieve the desired energy conservation goals, instead consume as much as 3 times of the predicted energy comsuptions, representing a significant building energy performance gap. This study aims to develop a pathway and stakeholder-engaged methodological framework

Air source heat pumps are vital for the implementation of coal-to-electricity policies in northern China. However, majority of the low-temperature air source heat pumps operate under a single and fixed mode, which may not be suitable for residential applications in regions with varied climates. Therefore, herein, a multimode single-fluid cascade air source heat pump (MSC-ASHP) is proposed, which includes

The EU has adopted several policies to improve energy efficiency. One of these policies aims to achieve energy efficient renovations in at least 3% annually of buildings in EU. The aim of this study was to provide an accurate economic comparison between three similar multi-family buildings that have undergone the same energy efficiency measures, with essential differences regarding the installed ventilation

Building owners usually select energy efficiency measures (EEMs) by referring to return on investment (ROI). Current studies tend to apply static energy price to estimate ROI. However, more and more buildings are adopting dynamic electricity pricing programs. To understand how electricity pricing programs impact the selection of EEMs, this paper presents an analysis of the ROIs of EEMs under different

In order to accurately and quantitatively describe the influence of a building’s spatial environment on subjective human perception, this research establishes a relationship framework between the spatial environment and subjective feelings, with the goal of improving occupant satisfaction and work efficiency. In pursuit of this goal, this study presents actual scenes through virtual space and introduces

Meeting thermal comfort in buildings with high latent loads requires the treatment of the air humidity with specific technologies. Desiccant based systems have proved to be effective in removing ventilation latent load in heating-ventilation and air conditioning systems. Typically, desiccant based systems are part of the air-handling units, which control both temperature and humidity. Based on the

This paper studies a mechanism to investigate and to improve the energy efficiency of a solar water heating system (SWH) in a hospital building located in Singapore. We utilize the data collected from Internet-of-Things (IoT) to gain information on different environmental and operational aspects of the considered system, that determine opportunities for improving the efficiency of various sub-systems

There is an ever-increasing interest in radiant cooling systems (RCSs) due to their energy-saving potential and improved indoor thermal environment in modern buildings. In this part of the review, an overview of established practices and recent efforts in modeling, simulation, operation, control, and integration of RCSs is provided. Models and simulation tools are essential for reliable planning and

Manufacturing industries play an important role in economic development, but a large amount of energy is consumed in the removal of pollutants and heat generated on the manufacturing floor. An efficient ventilation system is needed for improving indoor air quality and thermal comfort at reduced energy cost. This study studied a displacement ventilation system with diffusers around columns for a machining

Rich solar energy resources in plateau areas of Western China are suitable for local heating. However, common solar heating systems face the potential hazard and maintenance difficulties caused by climatic conditions. In this paper, the solar hot air heating system using the air medium evacuated tube collectors (ETCs) with embedding phase change materials (PCM) was discussed, which can be a good solution

It has been acknowledged that as outdoor temperature and relative humidity increase past threshold values, so do older people mortality and morbidity rates. Similarly, there exist indoor conditions of temperature (Tamb) and relative humidity (RH) that would pose a health-risk to older people when they are exposed to these conditions for extended periods. However, these indoor conditions need to be

To expand the use of wind energy, this paper proposed an off-grid ice storage system driven by distributed wind energy using ice storage to partly replace batteries with wind-electric-cold conversion. The current research aimed to achieve stable and efficient conversion of wind-electric-cold through control method. A system energy transfer model was established to study the energy utilizing efficiencies

Worldwide, China has the largest district heating (DH) area and is also the fastest growing country. This paper presents field measurement results for operational energy consumption from 38 DHSs to fill in the gaps in understanding of the current operational issues of the district heating system (DHS). The average heat consumption during the heating period was 98.6 kWh/m2 and the monthly average electricity

Reverse cycle defrosting is widely used for air source heat pumps. When a multi-circuit heat exchanger is vertically installed in a heat pump as an outdoor coil, the melted frost could be kept downwards flowing or locally drained during defrosting by using water collecting trays. To analyze the performance differences of melted frost, two defrosting models were developed and previously reported by

This paper presents a systematic GIS-based methodology to obtain the shadow cast profile of a group of buildings on arbitrarily orientated and tilted surfaces. The model is integrated in the widely-employed 2D-GIS environment. Given its scalability, the methodology can be easily applied from a local level up to a district, city or even regional level. This work is of interest for a wide range of applications

Variable refrigerant flow (VRF) systems are widely-adopted air conditioning systems. When system faults occur in VRF systems, the efficiency of VRF system will drop drastically. This paper presents a single 1-D CNN model and an ensemble model with parallel 1-D CNNs for diagnosing VRF system refrigerant charge faults under heating condition. From the cleaned experiment data of a commercial VRF system

China has a large number of existing public buildings and rapidly growing energy demand of public buildings. For this reason, the government and the relevant administrative sections have issued many policies, regulations, and incentives to decelerate the growth of the energy consumption of public buildings. However, the diverse types of buildings, as well as different design standards and construction

In a warming planet, overheating is becoming an increasingly important issue at all latitudes and locations, even in areas which traditionally did not have this problem. Passive cooling systems improve thermal comfort in a hot climate using a fraction of the energy used by conventional mechanical systems. This paper investigates the performance of a novel passive cooling system, a hybrid green roof

Homes contribute 22% of UK carbon emissions, 45% of which are primarily for space heating energy. Delivery of highly insulated homes, new build and retrofit, is needed to help meet the UK’s 2050 net zero carbon target. Similar policies are being adopted across the developed world to limit rising carbon emissions. Unfortunately, most new and retrofitted buildings use as much as 250% more energy than

Standard methods to associate GHG emissions with electricity use are aggregated over broad space and timescales which lead to inaccurate estimates. This paper presents a methodology which accounts for both spatial and temporal sensitivity when calculating GHG emissions from electrical grid while also considering interregional transfers. The methodology presented is generalized enough for any electrical

Nowadays worldwide directives have focused the attention on improving energy efficiency in the building sector. The research of models able to predict the energy consumption from the first design and energy planning phase is conducted to improve building sustainability. Use of traditional forecasting tools for building thermal energy demand tends to encounter difficulties relevant to the amount of

The thermal performance gap in buildings is defined as the difference between the theoretical and the actual energy consumption for heating, and is known to undermine energy retrofit strategies and policies. This study examines the performance gap in retrofitted buildings using the Swiss Cantonal Energy Certificate for Buildings (CECB) database, using a sample of 1172 buildings for which both theoretical

This paper proposes the application on microscale of an innovative trigeneration system with micro CAES (Compressed Air Energy Storage) – TES (Thermal Energy Storage) and the integration of renewable energy production, focusing on the potential use for air conditioning and domestic hot water systems. The system allows storing mechanical energy in the form of elastic and thermal potential of compressed

HVAC systems occupy a large part of the building’s energy consumption. The development of fault detection and diagnosis (FDD) techniques for HVAC system is becoming increasingly essential for building energy saving. The present paper proposes a comparison study on the basic data-driven methods for variable refrigerant flow (VRF) system fault diagnosis. And five widely used data-driven methods were

Domestic energy retrofit has significant potential in reducing carbon emission and energy demand. However, the actual energy saving from retrofit projects often falls short of expectations. One of the main reasons for this is occupant behaviour being addressed inadequately in energy models. Large variations in occupant behaviour may not have been considered (or are averaged) when making predictions

Liquid desiccant dehumidification systems show significant energy-saving potential in HVAC applications. The dynamic characteristics of a liquid desiccant dehumidifier attract increasing attentions in recent years, which are essential for designing appropriate controllers for it. However, due to the complicate coupling of heat and mass transfer inside the dehumidifier, there are few models have been

Building energy prediction techniques are the primary tool for moving towards sustainable built environments. Energy prediction models play irreplaceable roles in making energy policy and the development of the building sector. This paper presents a comprehensive review of the prevailing prediction techniques used in large-scale building energy applications under different scopes and different archetypes

The solar incidence on an indoor environment and its occupants has significant impacts on indoor thermal comfort; it can bring favorable passive solar heating or can result in undesired overheating (even in winter). With the increasing use of glazing in modern buildings, this problem has become more critical for both building design and energy use. Conventional indoor thermal comfort indictors and

It has been known that the actual operating performances of a space heating ASHP unit are significantly impacted by the joint effect of ambient air temperature, Ta, and relative humidity, RH. To enable a convenient evaluation of the operating performances of a space heating ASHP unit with a reasonable accuracy, an equivalent temperature drop (ETD) method has been developed. The ETD method transferred

Historic artefacts must be properly preserved if they are to be transmitted to future generations. Indeed, several methodologies and guidelines that aim to safeguard artefacts by limiting the ranges in which the indoor temperature and relative humidity vary exist, which means energy consumption. This paper aims to quantify the energy consumption associated to three different setpoints and respective

The reduction of the energy demand of existing buildings is the main objective of building refurbishment. Managing the heat radiation properties of the wall construction is a possible way to develop highly effective and resource efficient insulation materials and concepts. The application of infrared reflective wall paints and coatings has been studied since the latter half of the 20th century. A brief

Currently, the conventional design method for ASHPs is only to ensure that the required output heating capacity at specific rated conditions can be provided, without considering the impacts of frosting on the operating performances including the output heating capacity of ASHPs when operating at different regions with different climate conditions. Therefore, in this paper, a novel design method for

The building sector is a critical sector to achieving China’s energy conservation and emission reduction targets because it has contributed to more than 30% of the national energy consumption in the past decade. Green building construction has become a nationwide trend with the aim of energy conservation. The science research building of China State Construction Technical Center (CSCTC) has been labeled

An energy pile is a special form of vertical ground heat exchanger that couples the roles of structural support and heat transfer. Modeling the transient heat transfer process inside an energy pile has importance; however, available analytical models either have insufficient calculation accuracy or are computationally demanding. Based on three existing models, this paper proposes a novel short-term

Data visualization is an important resource for decision makers to obtain information from large datasets. Based on the data obtained from either predictions or measurements, different strategies are combined and tested to reduce the energy demand, whilst keeping the indoor comfort at suitable level. Although the information expressed from data representation can significantly influence the decisions

The issue of transmittance of thermal bridges in existing buildings has been addressed aiming to achieve correlations able to evaluate the ground-contact thermal bridges. A bi-dimensional steady state FEM model has been implemented to simulate wall-to-floor structural node and then validated in accordance with the EN ISO 10211:2017 standard. Different construction joints have been then simulated for

To realize the goals of energy transition, becoming energy-neutral at the neighborhood level by sharing energy among clusters of heterogeneous buildings with local distributed energy resources (DERs), will play a vital role. However, uncertainties related to demand and renewable sources pose a major operational challenge to schedule the DERs. In this paper, a scenario-based mixed-integer linear programming

With the use of computer-aided tools, design of high-performance buildings is becoming the de-facto industry practice. While reliability and ingenuity of computer simulation models is debated on one hand, continuous measurement and verification of building performance over a long-term is embraced as an alternative solution. The goal of this study is to assess the energy performance of a state-of-the-art

The applicability of common defrost technologies depends on how easy it is for air source heat pumps to frost under local climate conditions. At the same time, the degree of frost formation of the air source heat pumps outdoor units are mainly affected by local climatic conditions. Therefore, this study proposes the concept of frosting degree hours, which is used to specifically characterize the impact

A latent thermal energy storage system designed for domestic hot water is constructed using microencapsulated phase change material (MEPCM) as the energy storage medium. The temperature response and energy storage are experimentally investigated for different MEPCM particle fractions, PCM core fractions and carbon fiber fractions in the energy storage units (ESUs). A model for nominal energy storage

This paper presents an innovative ground heat exchanger with double-circuit, GeoUWT (Geothermal Underground Water Tanks), and the required preconditions for installing this kind of configuration in the livestock sector. Dedicated Thermal Response Test was conducted on the test site to represent barn conditions and to estimate the heat exchange capacity of the GeoUWT in a realistic case study performance

Thermal bridges accounted for 30% of the impact on the energy performance of European residential building stock. Nevertheless, European countries and their standards do not take into account the influences of this type of anomaly. Furthermore, current methods for quantifying thermal bridges have three main drawbacks. Firstly, most of approaches consist of complex models based on fluid dynamics or