bluuebunny/crossref_metadata_2025_split huggingface dataset:
Wood burning habits and its effect on the electrical energy demand of a retrofitted Norwegian detached house
Authors: Felius L. C. , Thalfeldt M. , Georges L. , Hrynyszyn B. D. , Dessen F. , Hamdy M. 
Published: October 2019

Abstract
Using firewood as a space heating source is a popular solution in Norwegian housing and can significantly reduce the electrical energy demand of houses. This study analysed habits and reasons for using a wood stove from survey data. From this, typical behaviour patterns were defined. These patterns were imported into a building performance simulation model of a typical Norwegian single-family detached house to evaluate the impact of the stove user behaviour on the electrical energy demand and on the overheating risk. Results showed that up to 32% of the electrical energy demand for space heating can be saved using a wood stove. The number of overheating hours increased when the wood stove was used more frequently. However, it decreased after full renovation because the stove is used less often, as the total space heating demand decreases and the indoor temperature drops less often below the temperature set-point when the stove is started. Active use of the wood stove is effective as retrofitting measure when the aim is to save electricity or fossil fuels. Nevertheless, if the stove power is not adapted to the building, it can be challenging to maintain a comfortable temperature in the room.
Designing a ZEN Campus: An exploration of ambition levels and system boundaries
Authors: Skaar Christofer , Solli Christian , Vevatne Jonas 
Published: October 2019

Abstract
The Norwegian University of Science and Technology (NTNU) is gathering from dispersed locations to one central campus at Gløshaugen, requiring an estimated 92 000 m2 new buildings and upgrading 45 000 m2 of existing buildings. NTNU has high environmental ambitions for the new campus, including zero-emission ambitions. This paper explores system boundary definitions and ambition levels in a Zero Emission Neighbourhood (ZEN) context. A key element is a plus energy campus that provides a surplus of renewable energy in the operational phase, that can compensate the carbon footprint of buildings, infrastructure and mobility. Preliminary energy and carbon analyses of the campus have been performed A key result is an overview of design choices and methodology choices for concept stage calculations for a zero-emission campus. Six system boundaries have been defined, with the production to consumption ratio varying from 19 % to 132 %. The lowest includes all buildings, the highest includes production from all buildings, but consumption only from new and renovated buildings. The main finding is that it is possible to realise a plus energy campus for new and renovated buildings, but not including non-renovated buildings. A plus energy campus requires a combination of PV and seasonal energy storage.
Defrosting and Frost Protection Measurements of Heat Recovery in Cold Climate
Authors: Johansson D , Wahlström Å , Dahlblom M 
Published: October 2019

Abstract
The installation of technical solutions for heat recovery from the ventilation air is a very important step, both with respect to improving the indoor climate and as an energy-saving measure. Ventilation without heat recovery use a substantial part of an entire building’s heating use, especially if the building is a low energy building. To realize a large implementation of heat recovery property owners must increase their knowledge about how these systems work and they must be able to rely on them functioning properly. The function and performance of a ventilation system when it comes to heat recovery can be a problem as soon as temperatures drop far below zero. When freezing occurs some form of defrosting is required and this can lead to indoor climate problems and to little or no heat recovery being obtained, which will reduce the energy efficiency and, at the same time, may compromise moisture safety. The goal of this project is to increase knowledge about how heat recovery systems for residential buildings with respect to defrosting and frost protection measures in heat exchangers. The knowledge can thereafter be used to develop effective defrosting strategies and frost protection measures so that the energy use and power requirements are minimized. Measurements were performed for heat recovery systems placed in dwellings in north Sweden to investigate occurrence of frost formation. The paper will present these measurements and some comparing simulations which can serve as a basis for further development of good defrosting strategies.
A Norwegian zero emission neighbourhood (ZEN) definition and a ZEN key performance indicator (KPI) tool
Authors: Wiik Marianne Kjendseth , Fufa Selamawit Mamo , Andresen Inger , Brattebø Helge , Gustavsen Arild 
Published: October 2019

Abstract
Within the Norwegian Research Centre for Zero Emission Neighbourhoods (ZEN) in smart cities, a definition for achieving zero emission neighbourhoods will be developed and tested against nine pilot areas. The ZEN definition considers a series of assessment criteria and key performance indicators (KPI) under seven categories; GHG emissions, energy, power/load, mobility, economy, spatial qualities and innovation. This paper presents the first draft of the ZEN definition, and discusses some of the opportunities and challenges in implementing assessment criteria and KPIs (ZEN metrics) into a ZEN KPI tool. This paper briefly presents the ZEN pilot areas and maps out existing tools used by ZEN stakeholders for the documentation of ZEN metrics. The paper goes further by presenting a ZEN KPI tool conceptual framework for the implementation of the ZEN definition in ZEN pilot areas and outlines a specification for the future development of a ZEN KPI tool. Finally, the paper presents further work for the development of a ZEN KPI tool.
Using residential buildings to manage flexibility in the district heating network: perspectives and future visions from sector professionals
Authors: Andersen P V K , Georg S , Gram-Hanssen K , Heiselberg P K , Horsbøl A , Johansen K , Johra H , Marszal-Pomianowska A , Møller E S 
Published: October 2019

Abstract
Intermittent energy resources challenge the ways in which the existing energy system operates. Studies suggest that residential buildings can provide a flexibility service for district heating (DH) systems. This technique involves load shifting by heating buildings to higher temperatures at times when energy is more readily available, thus diminishing heating needs at times of peak demand or when energy is scarce. Based on three Future Workshops (FWs) where DH professionals and other relevant DH stakeholders participated and discussed this topic, this paper reports on the extent to which these actors see energy flexibility as a realistic future development, and on what they see as key potentials and challenges in that regard. Preliminary results indicate that the mix of the actors and the specific local context greatly influence how this topic is understood, emphasizing the importance of including local context in investigations of energy flexibility. FW participants included representatives from DH companies, municipalities, building associations, technology developers, etc. The FWs were conducted at three different localities of Denmark: Copenhagen, Aalborg and Sønderborg, i.e. the national capital, a regional capital and a smaller city, respectively.
Efficiency of BIPV system – Field study in Norwegian climate
Authors: Gullbrekken Lars , Bunkholt Nora Schjøth , Grynning Steinar , Bellman Martin , Kvande Tore 
Published: October 2019

Abstract
Use of solar cells (PV) and solar collectors are key remedies in buildings where a large part of the energy supply should be based on renewable energy. The aim of this work has been to evaluate calculated and measured solar production of two identical BIPV roofs located at the ZEB Living Laboratory situated at NTNU-campus in Trondheim. Temperature, irradiance and wind speed and direction at the rooftop of the building have been monitored since the construction of the house. There was found a large difference in energy production of the northern roof section and the southern. One possible explanation is shading of the northern roof because of low solar azimuth during the measuring period. In order to avoid such disadvantages, design of the PV-roofs should be considered early in the design phase of the building project. A small difference was found between the hourly measured and the calculated values of the PV performance based on the monitored local climate data. Use of generic climate data expect to cause a larger difference between measured and simulated energy performance due to lack of consideration to local conditions.
Relation between daylight availability and electric lighting in a single-family house
Authors: Lobaccaro G , Savarino M , Goia F , Fabrizio E 
Published: October 2019

Abstract
Daylight availability is an important aspect that can potentially improve both the quality and the energy performance of buildings. However, it is not always straightforward easy to assure that an increase in the daylight availability leads to a reduction of electric energy use for artificial lighting. In this study, experimental measurements and numerical simulations were conducted to analyse the relation between the uses of artificial light and the daylighting availability for different groups of users who lived for one month each in a Zero Emission Building single-family house located in Trondheim, Norway. The use of electric lighting and the outdoor environment conditions (irradiance and illuminance on the horizontal plan) were recorded through advanced daylighting simulations, carried out with DIVA-for-Rhino, the daylighting availability during the periods of occupancy was then reconstructed, using as input data the outdoor environmental variable recorded during the experimental analysis. The results show that the coefficient of correlation between daylight availability and the artificial light is in general low and the use of artificial lighting seems to be largely independent from the availability of natural light.
Geo-Solar District Heating – Lessons Learnt from a not Realised Project
Authors: Schmidt Dietrich , Stroh Kilian 
Published: October 2019

Abstract
For the new housing area with approx. 130 low energy residential houses, located in Kassel, Germany, various supply concepts are investigated. Main objective of the project is the development of an innovative and optimised heat supply concept based on renewable energies and a low temperature district heating for later realisation.
During the course of the project several heat supply concepts have been investigated and compared to give an input to the decision and realisation process. A promising heat supply concept is based on a central ground source heat pump in combination with a low temperature district heating (40°C supply temperature) for space heating and decentralised solar thermal systems for domestic hot water preparation. The advantages of this supply variant are comparable low annual heating costs and about 60% lower CO2-emissions in comparison to the reference system (decentralized air / water heat pump with solar thermal system).
Due to time constrains it was decided not to realise the above mentioned energy concept. However, the research project took up the task to investigate the transferability of the concept in technological and economical perspectives to other locations and boundary conditions. From the results of the study the importance of a very high connection rate can be highlighted. Also the question of the particular business models for such capital demanding projects (high investment costs for the heating grid vs. low energy demand/sales) has been regarded.
Latent heat storage for centralized heating system in a ZEB living laboratory: integration and design
Authors: Sevault Alexis , Bøhmer Fabian , Næss Erling , Wang Liang 
Published: October 2019

Abstract
The ZEB Lab project, coordinated by SINTEF and NTNU, aims at building a ZEB (Zero Emission Building) in Trondheim (Norway) in 2019, to be used both as office building and living laboratory. An innovative latent heat storage (LHS) unit using phase change material (PCM) will be integrated in the centralized heating system. The LHS unit will be able to store excess heat from various heat sources connected to the heating system, when they are not required for space heating. One challenge is to make use of the full potential of the PCM latent heat to have a compact and effective unit, while the unit itself should have a low associated CO2-footprint. The LHS system consists of two units designed for a total heat storage capacity of 0.6 MWh, corresponding to the heat needed on top of the heat pump to cover for up to 3 consecutive days in the coldest period of the year, with a maximum combined effect of 26 kW. A bio-based wax is used as PCM with melting temperature 37 °C and measured latent heat 198 kJ/kg. Dynamic system modelling is used to support the design of the LHS unit and ensure sufficiently high heat transfer rates.
On the relation of thermal comfort practice and the energy performance gap
Authors: Hellwig Runa T 
Published: October 2019

Abstract
Recent research results from different countries show that although energy efficiency measures in buildings indeed led to lower energy use in buildings, there is a performance gap between the calculated energy use and the actual measured energy use in energy-efficient houses, leading to a higher energy use than predicted. Thermal comfort related behaviour is one out of manifold reasons contributing to this performance gap. Thermal comfort requirements are based on objectively measurable parameters. A number of contextual factors impact an individual’s thermal comfort perception and preference. Technological opportunities and material arrangements offer several ways to conditioning indoor environments. Research shows that they shape the occupants’ thermal comfort attitudes. Over time, technology as conditioning practice and insulation has led to different thermal comfort practice in buildings contributing to this performance gap. As humans show an excellent adaptation potential towards a wide range of temperature, enabling them to adapt to diverse climates but also seasonally, it follows also the adaptation process can work in the opposite direction. Hence, that with reduced exposure to outdoor weather and more narrow temperature ranges inside building humans might also adapt to indoor thermal conditions and get more sensitive to small indoor temperature changes, leading probably to higher indoor temperature over time (“indoor exposure rebound”). As our energy conservation efforts of the recent years show less effects than expected, it seems that the two mainly applied sustainability strategies efficiency and consistency have limited effects as they are affected by rebound phenomena. Sufficiency, as the third sustainability strategy, is not yet a generally accepted strategy. It refers to what has been described as “the right measure”. The question of what would be “the right measure” of indoor thermal comfort, meaning what thermal conditions would be sufficient, can be raised. Based on a discussion of findings from literature, it will be concluded that there is a need for a new thermal comfort thinking in climates which have the need for seasonal or all year round active conditioning leading to a more sufficient conditioning practice.
Case study of personal heaters in a Plus energy building – Simulations of potential energy savings and results from a field test
Authors: Lassen N. 
Published: October 2019

Abstract
Personal Comfort Systems (PCS) for heating, such as foot warmers, heated chairs and infrared heaters, can compensate for a lowering of up to 10°C in ambient temperatures in a heating situation. They are found to lead to a significant increase in occupant satisfaction with the thermal environment, as they enable for a personalized thermal environment. In this way, the use of PCS systems can ensure occupant satisfaction while widening the temperature dead-band, or difference between heating and cooling set-points in buildings. Several field studies from North America have indicated that the average dead-band between heating and cooling set-points is between 1 and 2 °C, leading to considerable amounts of energy used for over-heating and overcooling. This kind of systems may therefore be an important contributor towards Plus energy buildings, but they are seldom used. The objectives of this study were (1) to test PCS heaters in a modern Norwegian office environment and see how they are appreciated by office workers and (2) to investigate how large energy savings such systems can contribute to in a Plus energy building. Powerhouse Kjørbo was selected as a case building for the study. Potential energy savings were calculated using energy simulations. The results in this case study were not able to confirm an increase in occupant thermal acceptability rate due to the use of a PCS heater. Interviews of occupants however suggest that PCS heaters are a good solution for improving the satisfaction of the limited number of occupants who have special needs, preferences or are located in a place with lower temperature. In buildings with an effective heating source, such as ground source heat pumps, PCS solutions are not likely to contribute to notable energy savings. In an indirect way, they may however still contribute toward realizing Plus energy buildings as PCS systems can help relax the demands set to other climate installations in the building. This again can allow the use of more environmentally friendly solutions such as utilization of thermal mass, temperature stratification and natural ventilation. They can also reduce installation costs by eliminating the need for more complicated and costly HVAC systems.
The design process for achievement of an office living laboratory with a ZEB standard
Authors: Time Berit , Engebø Atle , Christensen Morten , Dalby Ola , Kvande Tore 
Published: October 2019

Abstract
ZEB Laboratory is a full-scale office building with a ZEB-COM ambition, searching a high degree of flexibility and where components and technical systems can be modified for research purposes. Project delivery of a living laboratory with a ZEB standard is not an easy task. The implementation of the ZEB method in a partnering contract as a project delivery model has been developed. This paper describes and elaborate the development of the project delivery and design process for ZEB Laboratory seen by the client. The ZEB Laboratory design and procurement process has given valuable insight and experience into the use of partnering and collaborative elements for planning and production of ZEB buildings.
Assessing buildings’ absolute environmental sustainability performance using LCA focusing on climate change impacts
Authors: Ohms Pernille , Andersen Camilla Ernst , Rasmussen Freja Nygaard , Ryberg Morten , Hauschild Michael , Birkved Morten , Birgisdottir Harpa 
Published: October 2019

Abstract
The building sector is of major concern when seeking to reduce the environmental impact of our society. A common tool often used in certification systems for quantification of environmental impacts is Life Cycle Assessments (LCAs). LCAs are traditionally used for relative comparisons, i.e. to assess whether one product or service performs better than another. Recently, a method for absolute evaluations based on the Planetary Boundaries, was coupled with LCA in order to define the boundary between environmental sustainability and unsustainability. In this study Planetary Boundaries-based Life Cycle Impact Assessment method has been applied to a case study of six single family stand-alone dwellings to assess whether these buildings can be considered absolute sustainable relative to the Planetary Boundaries. The results from the assessment indicate that irrespective of the design strategy used for the six houses and future increase in the use of renewables for electricity and heat production, it is unlikely that any of these houses can be regarded as sustainable in absolute terms. This underlines that more radical changes are needed in the way buildings are constructed and used in order for buildings to become environmentally sustainable.
Co-Creation of Positive Energy Blocks
Authors: Ahlers Dirk , Driscoll Patrick , Wibe Håvard , Wyckmans Annemie 
Published: October 2019

Abstract
A main challenge in building carbon-neutral built environments is the ability to scale and replicate solutions. We examine how to develop low-carbon neighbourhoods and districts, while aiming at climate-friendly and sustainable livable urban environments. We take a view that not only scales up individual building solutions, but embraces the added complexities arising from the scale change and utilizes them for a novel approach. It includes a strong focus on co-creation and open innovation to develop sustainable solutions.
In this contribution, we present the approach of the +CityxChange project in implementing Positive Energy Blocks (PEB) through a European H2020 project from the topic of Smart Cities and Communities. A PEB comprises several connected buildings that have a averaged yearly positive energy balance between them. This definition excludes embodied emissions, but allows to focus on the infrastructure and systems between buildings as part of the built environment, and ways to implement and incorporate them within existing cities. The +CityxChange approach relies on co-creating Europe-wide deployment of Positive Energy Districts, with Integrated Planning and Design, Creation of a Common Energy Market, and CommunityxChange with all stakeholders of the city.
Building Bioclimatic Design in cold climate office buildings
Authors: Ness M C , Andresen I , Kleiven T 
Published: October 2019

Abstract
Building Bioclimatic Design (BBCD) understands architecture as a filter between outdoor climate and indoor comfort. This way, it encourages the exploitation of freely available climatic resources, before adding any HVAC system. Therefore, BBCD represents a fundamental strategy for improving energy efficiency in buildings. The climate / comfort comparison in building design determines the passive strategies that are most suitable for a specific climatic context, as well as the level of architectural complexity. In cold climates, it would suggest the use of compact shapes and extremely airtight and insulating envelopes, in order to minimize heat losses while maximizing solar heat gains. However, when combined with high internal gains, these measures might cause overheating problems in the warm seasons. That is the case of office buildings, where cooling equipment is included as default even in cold climates, drastically increasing their energy consumption. It is therefore becoming a necessity to consider here the adoption of passive cooling strategies once identified with warmer climates. The aim of this research is to explore how the theories and tools for BBCD could be applied to cold climate office buildings. In order to study the effect of the different climatic contributors, we will use Building Performance Simulation to analyse relevant cases with EnergyPlus (in combination with DesignBuilder). This will in turn help drawing suggestions on how to adapt the Building Bioclimatic Chart (BBCC) for its application to cold climate office buildings in practice. It is well known that the earlier we apply the measures for energy efficiency, the greater their effect and with higher degree of integration. The BBCC is used in the pre-design phase to determine the most suitable passive strategies for climate adaptation and control, informing the design as early as possible along the process. This study can contribute to the development of zero emission neighbourhoods in cold climates, by improving the energy efficiency of their buildings. Additionally, it complements the existing research in BBCD by extending its application to cold climates and office buildings.