Search results

The purpose of this paper is to evaluate long-term effects of previous policies for energy efficiency on energy performance and heritage values. A further ambition is to better understand the relationship between energy and preservation by exploring a quantitative method of combining energy performance data with official heritage designation.

The study is based on a quantitative analysis of energy performance, completed additional insulations, and official heritage classification for individual buildings. Data have been collected and analysed for a sample consisting of 289 multi-family buildings heated with district heating and constructed 1940–1949 in an urban area in Stockholm, Sweden.

The data exhibit a significant correlation between the studied features. The study further shows that additional insulation has been installed in roughly half of the buildings. The large majority of them were carried out in the national programme for home improvement called ROT.

The findings indicate that previous policies for energy efficiency had an important effect on energy performance and heritage values in the studied area. They continue to affect urban planning and building permit administration today. Research of the physics of individual buildings would be needed in order to determine the reason for differences in the sample.

By presenting a novel method, the study provides a useful tool for policy makers to bridge the gap between issues of energy and preservation and adopt a more holistic approach towards a sustainable built environment.

This paper aims to present a novel lightweight distribution grid operating robot system with focus on lightweight and multi-functionality, aiming for autonomous and live-line maintenance operations.

A ground-up redesign of the dual-arm robotic system with 12-DoF is applied for substantial weight reduction; a dual-mode operating control framework is proposed, with vision-guided autonomous operation embedded with real-time manual teleoperation controlling both manipulators simultaneously; a quick-swap tooling system is developed to conduct multi-functional operation tasks. A prototype robotic system is constructed and validated in a series of operational experiments in an emulated environment both indoors and outdoors.

The overall weight of the system is successfully brought down to under 150 kg, making it suitable for the majority of vehicle-mounted aerial work platforms, and it can be flexibly and quickly deployed in population dense areas with narrow streets. The system equips with two dexterous robotic manipulators and up to six interchangeable tools, and a vision system for AI-based autonomous operations. A quick-change tooling system ensures the robot to change tools on-the-go without human intervention.

The resulting dual-arm robotic live-line operation system robotic system could be compact and lightweight enough to be deployed on a wide range of available aerial working platforms with high mobility and efficiency. The robot could both conduct routine operation tasks fully autonomously without human direct operation and be manually operated when required. The quick-swap tooling system enables lightweight and durable interchangeability of multiple end-effector tools, enabling future expansion of operating capabilities across different tasks and operating scenarios.

The purpose of this paper is to analyze the impact of design solutions used in clothing on the thermal resistance of the material systems from which the clothing is made, design solutions used in clothing on its thermal insulation and clothing size on its thermal insulation properties.

This study involved laboratory tests of clothing protecting against cold and textile systems used in this type of garment using a “skin model” test stand and a thermal manikin.

Analysis of the results obtained from tests carried out showed that the design solutions used in a garment can model its local and overall insulation. It was found that using a bib in trousers has a dominant influence on the thermal properties of clothing. An important parameter is also the use of a hood, as well as the length of the jacket. No significant effect of other structural solutions, such as jacket fastening, pockets and reflective tapes, on the thermal performance of the clothing set was noted.

Although the reports available in the literature pay a lot of attention to the impact of the design of clothing protecting against cold on its thermal performance, most of the presented research results relate to the aspects of fit, whereas the analyses of the effects of other aspects of garment construction on thermal properties are lacking. Therefore, the analysis of the impact of design solutions used in clothing on its thermal insulation properties is a key original factor of this paper.

Dwellings constructed before 1920 often had solid brick walls with poor thermal performance. Today there is a drive to reduce both energy demand and carbon dioxide production. The purpose of this paper is to demonstrate that mixtures of chopped hemp straw with lime based binders added to the external surface of brick walls can substantially reduce the air to air thermal transmittance, or U‐value W/m² K, and that these mixtures provide a sustainable remedial treatment for solid brick walls. The aim is to achieve wall U‐values as good as, or better than, the current UK Building Regulations design value of 0.30 W/m² K.

Several Microsoft Excel spread sheets have been constructed to determine the steady state and transient thermal properties of various brick walls. These spread sheets are validated by comparing their output with the published thermal data to be found in the CIBSE Design Guide. The sustainable aspects of a number of different externally hemp‐lime insulated Victorian brick walls are described and discussed.

The U‐values and the transient thermal properties of solid brick walls with thickness 110 mm, 220 mm and 340 mm are presented. The transient properties include the admittance, decrement factor and lag time. These walls are then considered with various added external layers of hemp‐lime ranging in thickness from 50 mm to 300 mm. Some solid brick walls have an added air cavity, created with studding and plywood sheathing, before the layer of hemp‐lime. Walls with external tile hanging for sites with high exposure to driving rain are also discussed.

The paper demonstrates the advantages of the energy saving and carbon dioxide sequestration achieved by adding 200 mm of a hemp‐lime binder insulation to the exterior of Victorian brick walls of terraced dwellings.

The purpose of this investigation was to measure the changes in effective thermal insulation caused by three different types of outer garment ventilation features (chest zips, back zips and pit zips) when combined with either a high or low air permeability insulating layer.

The measurements in this investigation were made with a thermal manikin and with a 26 zone thermal torso. Measurements were made at two air flow speeds with each manikin; the different air flow characteristics for each manikin allowed investigation of how ventilation features interact with different air flow distributions.

It was established in this study that high permeability insulation increases the efficacy of ventilation features by an average of 7 per cent at the low wind speed and 10 per cent at the high wind speed. No particular ventilation feature was found to be consistently the most effective; the data suggest that garment openings should simply be located in well-ventilated areas.

This investigation analysed the ventilation characteristics of protective clothing ensembles with different ventilation features, allowing designers to create more comfortable clothing for work and leisure activities.

This paper investigates thermal mass performance (TMP) in hot climates. The impact of using precast concrete (PC) as a core envelope with different insulation materials has been studied. The aim is to find the effect of building mass with different weights on indoor energy consumption, specifically cooling load in hot climates.

This research adopted a case study and simulation methods to find out the efficiency of different mass performances in hot and humid climate conditions. Different scenarios of light, moderate and heavyweight mass using PC have been developed and simulated. The impact of these scenarios on indoor cooling load has been investigated using the integrated environment solution-virtual environment (IES-VE) software.

The results showed that adopting a moderate weight mass of two PC sheets and a cavity layer in between can reduce indoor air temperature by 1.17 °C; however, this type of mass may increase the cooling demand. On the other hand, it has been proven that adopting a heavyweight mass for building envelopes and increasing the insulation material has a significant impact on reducing the cooling load. Using a PC Sandwich panel and increasing the insulation material layers for external walls and thickness by 50 mm will reduce the cooling load by 15.8%. Therefore, the heavyweight mass is more efficient compared to lightweight and moderate mass in hot, humid climate areas such as the UAE, in spite of the positive indoor TMP that can be provided by the lightweight mass in reducing the indoor air temperature in the summer season.

This research contributes to the thermal mass concept as one of these strategies that have recently been adopted to optimize the thermal performance of buildings and developments. Efficient TMP can have a massive impact on reducing energy consumption. However, less work has investigated TMP in hot and humid climate conditions. Furthermore, the impact of the PC on indoor thermal performance within hot climate areas has not been studied yet. The findings of this study on TMP in the summer season can be generated in all hot climate zones, and investigating the TMP in other seasons can be extended in future studies.

Sweden, like other countries, has set ambitious national targets for both energy efficiency and conservation of heritage values in the built environment. However, how these policies are implemented on a local level and how they affect each other is not known. This study aims to argue that extensive energy-saving policies can have unintentional impacts not just on the built environment but also on conservation practice.

By using a longitudinal approach, the aim is to investigate the possibilities of conserving the built environment when policies for increased energy efficiency are implemented in existing urban areas. The methodology used is qualitative, applying a combination of study of public records, policy documents, interviews with public officials and ocular investigation of buildings in three areas located in two different municipalities.

The study suggests that extensive refurbishments not only have effects on the character of an area, but in extension, affect how urban planners and local authorities approach the development in the same area. Urban areas affected by extensive retrofits in the past seem to be managed in less detail, leaving existing policy measures on both energy and heritage untapped.

This is a study concerning two Swedish municipalities. Furthermore, it is limited to one specific policy measure, energy-saving subsidies provided in the 1970s and 1980s. The generalisability of the findings may, therefore, be limited. Despite this, the findings provide an important indication of the relationship between energy-saving policies in the past and urban planning practice of existing urban areas today, as well as the importance of alignment between policy-making and implementation.

Policy instruments for the building stock and the practice of conservation planning have not worked well together. Due to local practice, energy subsidies provided in the 1970s and 1980s still today have a negative effect on both heritage conservation and energy efficiency in existing areas.

There is a discrepancy between expectations and outcome of policy measures. National decision-makers overestimate the possibilities to control the development on a local level, for both energy efficiency and heritage values. By examining an innovative set of sources, acknowledging long-term effects and entanglements of policies and practice, this study contributes to a better understanding of the complexity of different values in the built environment.

By comparing the share of approved applications, as well as completed energy retrofits, this study demonstrates that the effects of the national energy subsidy policy differed significantly between urban areas. Areas with a high degree of approved subsidies also had a high degree of retrofits, suggesting that the policy had intended effects. In these areas, the number of retrofits were also significantly higher than the number of subsidies. This was not the case where energy subsidies were fewer, which indicates that energy retrofits are performative, meaning that they accelerate further retrofits in the same area.

This paper aims to present the problem of heating the damaged insulation of an orbiter.

Changes of the insulation’s thermal properties, made by adding conductive material of high value of specific heat in a form of a dope to the protective layer, were examined. An iterative algorithm determining a variable of dope concentration in the material was developed.

Determination of distribution of conductive material concentration was made for materials which, after verification, demonstrated the most beneficial effect on protective properties of the modified insulation layer. The problem of determining the distribution of metal filings concentration in the insulation layer of the coating belongs to inverse heat conduction problems.

Change of properties was to enable time extension of the LI900 insulation tile heating up to the maximal temperature and, additionally, to lowering this temperature.

Although vacuum insulation panels (VIPs) are thermal insulators that combine high thermal performance with limited thickness, application in the building sector is still rare due to lack of scientific knowledge on the behaviour of these panels applied in building constructions. This paper, therefore, seeks to give an overview of the requirements for and the behaviour of VIPs integrated into building components and constructions. Moreover, the interaction between different requirements on and properties of these integrated components are discussed in detail, since a desired high quality of the finished product demands an integral approach regarding all properties and requirements, especially during the design phase. Therefore, the importance of an integral design approach to application of VIPs is shown and emphasized in this paper.

To achieve this objective, the legally and technically required properties of VIPs and especially their interrelationships have been studied, resulting in a relationship diagram. Based on these investigations of thermal‐ , service life‐ and structural‐properties have been selected to be studied more elaborately using experimental set‐up for structural testing and simulation software for thermal and hygrothermal testing.

Two relationships between requirements or properties were found to be of principal importance for the design of façade components in which VIPs are integrated. First, thermal performance requirements strongly interact with structural performance, principally through the edge spacer of this façade component. A high thermal performance requires minimization of the thermal edge effect, in most cases reducing the structural performance of the entire panel. Second, an important relationship between thermal performance and service life has been recognised. The operating phenomenon mainly governing this interaction is thermal conductivity aging.

Most research in the field of vacuum insulation until now has been directed towards gaining knowledge on specific properties of the product, especially on thermal and hygrothermal properties. The relationships and interactions between these properties and the structural behaviour, however, have been neglected. This paper, therefore, addresses the need for an integral design (and study) approach for the application of VIPs in architectural constructions.