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Intermittent heating, common in churches, requires higher heating power than steady state heating. With respect to energy use and preservation aspects, the heat up time should be short. Systems for intermittent heating are often designed using rule of thumb estimates or inadequate steady state calculations. This paper presents a method to relate heating power and heat up time for a specific building where thermal characteristics of a building are determined using a step response test. [ABSTRACT FROM AUTHOR]

[Display omitted] • Archetype development, model components and potential applications for UBEM are discussed. • Stochastic and dynamic occupancy models are among the most desired improvements for UBEM. • UBEM could be suitable for high accuracy predictions of future climate change scenarios. • Integration of socio-economic data in UBEM is promising but not currently applied. • Assigning value year from renovation records is tempting but could entail several pitfalls. Due to rapid urbanisation and the significant contribution of cities to worldwide energy use and greenhouse gas emissions, urban energy system planning is growing more important. Urban building energy modelling (UBEM) draws increasing attention in the energy modelling field due to its inherent capacities for modelling entire cities or building stocks, and the potential of varying data inputs, approaches and applications. This review aims to identify best practices and improvements for UBEM applications by examining previous research, with a focus on the currently least established approaches. Different archetype development procedures are analysed for common problems, six main under-developed input approaches or parameters are identified, and applications for future scenario development are surveyed. By analysing previous studies in related fields, this paper provides an overview of gaps in the published research and possible additions to future UBEM projects that can help expanding the existing modelling procedures. Comprehensive human behaviour models with additional aspects beyond occupant presence are identified as a major point of interest. Further research on socio-economic parameters, such as household income and demographics, are also suggested to further improve modelling. This study also underlines the potential for utilising UBEM as a tool for evaluating future climate change scenarios. [ABSTRACT FROM AUTHOR]

The indoor climate of historic buildings is governed not only by human comfort but also the desire to preserve these buildings and their interiors. For preservation, relative humidity is the most important parameter, including its amplitude and change rate. To control the change rate of relative humidity at a heat-up event for an intermittently heated massive historic building with heavy masonry walls, a simplified model for heat and moisture transfer at the heat-up time is presented. A method to derive the time constants and hygrothermal parameters of the building from measurements taken during a step response test is proposed and validated. The model with its parameters can be used to predict both heat-up time to reach the target temperature as well as the amount of moisture gained from the walls. These predictions are in turn used to calculate the decrease in relative humidity during the heat-up event. The indoor air relative humidity is predictable as it is determined by the air temperature and air mixing ratio. A control algorithm that uses the model for predicting and controlling the change rate of relative humidity by shaping the heating power is presented and validated using simulation results. • A model for heat and moisture transfer in intermittently heated historic building is presented. • The model is applied to predict heat-up time to a target temperature. • The relative humidity change rate is controlled by properly shaped heating power. • The proposed model-based control procedure is easy to implement on a low-cost heating system. [ABSTRACT FROM AUTHOR]

Building archetype identification is crucial for Urban Building Energy Modeling (UBEM), but is still considered one of the biggest challenges in this field. New methods of data acquisition, along with data mining techniques such as clustering, have recently received attention for the possibility of significantly increasing identification reliability and archetype accuracy. This paper aims to establish a new and simple clustering methodology for developing building archetypes for hybrid UBEM, using open data sets and multiple diverse variables, that is still reliable and possible to validate without the use of metered energy use or real building data. The methodology uses k -means clustering for 10 building parameters simultaneously, including socio-economic parameters obtained using spatial interpolation of statistical values. Building archetypes are successfully developed for the residential building stocks of two case study areas in Sweden. The results also show that the error metric values for multiple iterations diverge after a certain number of clusters, even when using the same clustering methodology on the same data set. This discovered effect, along with the combined use of one well-known and one novel error metric, constitutes a framework well adapted to accurately determining the optimal number of building archetypes. [ABSTRACT FROM AUTHOR]

The paper draws from the general literature on energy efficiency and historic buildings to explain the importance and potential of user-driven energy efficiency in historic buildings. It is the first review that places the user as a central object of study in the research field of historic buildings and energy efficiency. Relevant interdisciplinary topics and research results that make up the core of the field are presented and discussed in relation to user behaviour and its impact on energy consumption. The paper also investigates how user behaviour aspects can be integrated in a procedural approach to energy refurbishment in historic buildings. Research and experience from the building stock in general clearly shows how a user's awareness and behaviour, such as choice of temperature, zone heating and controlled airing, can have a significant effect on energy demand yet have no physical impact on the building. However, this has not received enough attention with regards to the historic building stock, where many physical energy efficiency measures can have negative impacts on the historic qualities of the building. Modification of user behaviour can therefore be a way not only to reduce energy demand but also to minimise the physical impact of increasing energy efficiency on historic buildings. The paper concludes that the current research agenda on historic buildings and energy efficiency has broken much ground but remains focused more on technical solutions than bottom-up user perspectives. Two main topics are identified as key barriers and future research fields: First, energy performance modelling is identified as a general barrier to developing sustainable strategies that promote user impact in historic buildings. Accurate energy modelling of historic buildings is a complex field reliant on the thermal interplay between user-building and building-district. Improved knowledge and intensified research is necessary to avoid distorted energy modelling results and unwanted rebound effects. Practical tools also require that the modelling can be used for trade-off scenarios where other sustainability aspects such as cultural heritage and economy are weighed in. Second, awareness raising in order to foster a deeper understanding and knowledge about the construction, system and cultural heritage values of a building is proposed as a key ingredient and driver for improved and sustainable energy behaviour. The paper argues that while user-driven energy efficiency represents an important resource for fostering less energy-demanding and less intrusive interventions in historic buildings, there are no guarantees for achieving the planned level of energy efficiency without taking into account user behaviour and the actual operation and energy performance of the historic building. To do this without risking negative consequences, improved decision-making processes are needed on policy, building and user level. An interdisciplinary bottom-up approach to energy refurbishment is presented. The essence of the model is that users and residents should always play a central role in the decision-making process because the well-being of the historic building will always depend on its day-to-day users, and vice versa. [ABSTRACT FROM AUTHOR]

Buildings account for 40% of total energy consumption in the European Union, yet at the same time they have considerable energy saving potentials. Historic buildings should be treated different from contemporary ones when it comes to energy improvements. The specifications which underline historical, sociocultural and architectural values require certain care during realization of energy saving implementations to sustain these values. The purpose of this study is to demonstrate how the energy efficient retrofitting in historic buildings should be managed in a transdisciplinary approach with a case study conducted on the historic building in İzmir—Turkey. A detailed building energy simulation tool was used to determine the impacts of energy efficient retrofits. The actual energy consumption of case building was based on the utility bills regarding electricity and heating fuel consumption. Building energy simulation tool was calibrated by comparing the measured and simulated indoor air temperatures and total energy consumptions. The inappropriate retrofits, which contradict to the cultural heritage values, were eliminated with a transdisciplinary approach. Later appropriate retrofits were gathered into three packages to evaluate their effects on the energy consumption. The results show that energy saving of more than 34% can be obtained without damaging the heritage values. [ABSTRACT FROM AUTHOR]

Highlights: [•] Energy renovation alternatives for historic rural houses are proposed. [•] Building service systems hold the largest single energy saving potential. [•] Of building structures, the insulation of external wall has the largest potential. [•] Cultural heritage values are possible to be taken into account in energy renovations. [ABSTRACT FROM AUTHOR]

• A novel approach for visibility assessment on buildings is proposed. • The new method is based on the target's instead of the observerâ;;s perspective. • Different definitions of the vantage area are evaluated. • Visibility is combined with PV and cultural-heritage values in two case studies. • The method can be used for city planning when visibility is important. Solar energy applications have, in recent years, become a common element in the urban landscape, especially on roofs and facades. However, it is important that the integration of solar energy in the built environment do not distort the fabric or expression of the existing building envelope, not at least in areas of high cultural-heritage values. The aesthetics depend, to a large extent, on how visible the new technology, such as photovoltaic (PV) panels, is. This paper describes a method for visibility assessment of building envelopes. It is referred to as target-based as it, in contrast to previously reported methods, bases the assessment from the perspective of the building envelope itself, rather than possible vantage points on the ground. The method was evaluated for two Swedish cities; Stockholm and Visby. In Stockholm, each building was evaluated based on its cultural-heritage values, solar irradiation and visibility. Deploying PV only on the roofs with the lowest cultural-heritage values, with insolation > 900 kWh/m2, and with no visibility from ground, results in a total PV yield of up to 2% of the total electricity demand. In Visby, various definitions of the vantage area were evaluated, from which the building envelope can be seen. It was found that the choice of vantage area greatly impacts the solar energy potential. If the vantage area is defined by the public domain, i.e., streets and other public open spaces, the non-visible roof area doubles compared to if all ground/terrain defines it. Compared to previous studies, the use of a vantage area, instead of discrete vantage points, seems to result in higher visibility of the roofs. [ABSTRACT FROM AUTHOR]