bluuebunny/crossref_metadata_2025_split huggingface dataset:
Retrofitting solutions for a campus building to mitigate urban heat island in a hot humid climate
Authors: Patil Vajreshwari , Bizcarguenaga Maite , Lieberknecht Katherine , Felkner Juliana 
Published: November 2021

Abstract
In this study we examine the summer cooling effects of trees and green facades on reducing urban heat island effects. Using ENVI-met model simulations, we investigate the influence of added greenery on the surface and ambient air temperature and its role on air fluctuations in the hot humid climate of Austin, TX, at pedestrian height. Under the specific conditions considered in this model, the results show the combination of trees and green facades has a greater cooling effect. Added greenery to the building mostly impacts the building's surface temperature during the hottest hours of the day, registering a maximum surface temperature reduction of 20.33°C. Simulations also show a maximum overall potential air temperature reduction of 0.54°C, and a maximum potential air temperature cooling effect near the building of 0.91°C. Future research should be conducted to address this study's limitations. Nevertheless, these findings can provide architects, designers, planners, and policymakers with a better understanding of the many benefits trees and green facades have, and provide them with the necessary tools to implement new solutions across sectors and scales to reduce the impacts urban areas have on the environment and provide a better living for all.
Development of a freely distributable CFD tool for approximate and detailed simulations of the flow around a complex of buildings
Authors: Decaix J , Jaboyedoff P , Duthé G. , El Sergany E. , Aiulfi L. 
Published: November 2021

Abstract
Indo-Swiss Building Energy Efficiency Project (BEEP) is a cooperation project between the Ministry of Power, Government of India, and the Federal Department of Foreign Affairs of the Swiss Confederation. Started in 2011, the project’s central focus is to help India mainstream Energy-Efficient and Thermally Comfortable (EETC) Building Design. BEEP works with building industry, policy makers, and building owners to catalyse adoption of EETC building design and technologies. India wants to avoid or reduce the use of air conditioning by improving natural ventilation at night, which requires numerical simulations to compute the flow around the buildings. However, the simulations of fluid flows are time consuming and are not used at the beginning of a project when the locations of the buildings are set. To improve the situation, a freely distributable environment based on the OpenFOAM toolbox has been developed providing two levels of resolution: an approximate level computing the flow in few minutes and a RANS level of simulation. The user inputs are limited to the geometry and the velocity direction and magnitude. The mesh and the numerical set up are automated. The accuracy of the two levels of resolution have been checked by computing test cases from the CEDVAL database.
Monitoring of photovoltaic systems and evaluation of building energy self-consumption
Authors: Cillari Giacomo , Fantozzi Fabio , Franco Alessandro 
Published: November 2021

Abstract
The spread of nearly zero energy buildings (nZEB), promoted by the strategies set in the path of decarbonisation, has made the integration of renewable energy systems (RES) in buildings a common and strategic practice; in particular, they most involve small to medium building integrated photovoltaic (BIPV) systems coupled with heat pumps (HPs). One major challenge deals with the implementation of high self-consumption (SC) schemes for the energy produced on site, essential to carry on a wider implementation of photovoltaic systems. The present paper addresses the effect of different sizing strategies on the SC levels of 3 systems installed on traditional and nZEB houses, with a peak power between 3.12 kWp and 5.98 kWp. The systems have been monitored recording the various energy flows involved. Different optimization strategies have been tested with the purpose of minimizing the interaction with the grid, according to SC and self-sufficiency (SS) indexes. The aim is to provide design guidelines for the correct sizing in a bottom-up approach. Results underlined the fundamental role of storage technologies. Approximately 6 Wp/m2 assure an optimal energy employment without storage, with SS index below 35%: the integration of small storage, 3-7 kWh/kWp leads to SS and SC index above 60% and 88% respectively.
Hydrogen-based electricity storage optimization on buildings by coupling thermal and photovoltaic electricity production towards carbon neutrality
Authors: Morier Y , Aguacil Moreno S , Couty P 
Published: November 2021

Abstract
Self-sufficiency (SS) of buildings with low greenhouse gas (GHG) emissions can be obtained using photovoltaics (PV). To maximize self-consumption - minimizing the import of grid electricity - PV can be coupled with a hydrogen storage system converting the electricity to hydrogen by electrolysis during the summer season, when the on-site production is higher, and using it during the winter season with fuel cells. This article deals with the sizing constraints of solar hydrogen systems at building-scale. The future building for the Smart Living Lab (SLL) in Fribourg (Switzerland) has been taken as case study. It has four stories and a mixed usage (Office-building and Research facilities), with a multi-oriented PV installation in order to produce enough electricity to achieve at least 50% of self-sufficiency. Using the PV production, this study aims to optimise the sizing of a hydrogen storage system allowing to reach the required self-sufficiency ratio. Finally, a comparison of the global efficiency of the system for three different demand-side scenarios.
Solar Thermal Regeneration of Borehole Heat Exchangers in Urban and Suburban Districts
Authors: Sauter David , Hunziker Manuel , Poppei Joachim , Cochand Fabien , Hubbuch Markus , Rohrer Jiirg 
Published: November 2021

Abstract
To prevent undercooling of the ground in densely populated areas, regeneration of borehole heat exchangers (BHEs), for example by solar thermal heat, may become necessary. However, the usable roof area is often small compared to the building’s heat demand, especially in urban areas. It was investigated how much regeneration is possible in districts that are supplied entirely by heat pumps with BHEs. Example buildings were modelled based on the buildings of two districts in Zurich. Uncovered PVT collectors and glazed flat-plate collectors were used as regeneration sources. The possible regeneration was determined in a simulation process that included the effects of mutual influences between the BHEs of neighbouring buildings. As expected, glazed flat-plate collectors allow for more regeneration than uncovered PVT collectors. For full regeneration, the required usable roof area relative to the annual heat demand is about 1.8m2/MWh for PVT and 1.2m2/MWh for flat-plate collectors. Large buildings often do not provide sufficient roof area for full regeneration. A sustainable heat supply of the entire district with regenerated BHEs can be possible in suburban neighbourhoods, if the bigger buildings are distributed rather evenly. In urban neighbourhoods, areas may exist in which solar thermal regeneration alone is not sufficient.
An energy-economic analysis of real-world hybrid building energy systems
Authors: Sawant Parantapa , Braasch Christian , Koch Manuel , Bürger Adrian , Kallio Sonja 
Published: November 2021

Abstract
A coordinated operation of decentralised micro-scale hybrid energy systems within a locally managed network such as a district or neighbourhood will play a significant role in the sector-coupled energy grid of the future. A quantitative analysis of the effects of the primary energy factors, energy conversion efficiencies, load profiles, and control strategies on their energy-economic balance can aid in identifying important trends concerning their deployment within such a network. In this contribution, an analysis of the operational data from five energy laboratories in the trinational Upper-Rhine region is evaluated and a comparison to a conventional reference system is presented. Ten exemplary data-sets representing typical operation conditions for the laboratories in different seasons and the latest information on their national energy strategies are used to evaluate the primary energy consumption, CO2 emissions, and demand-related costs. Various conclusions on the ecologic and economic feasibility of hybrid building energy systems are drawn to provide a toe-hold to the engineering community in their planning and development.
Residential rooftop PV power generation to support cooling loads and national targets in Saudi Arabia
Authors: Alam M , Alghamdi A S , Bahaj A S , James P A B , Blunden L S 
Published: November 2021

Abstract
Saudi Arabia (SA) has a high per capita electricity consumption, predominantly supplied from fossil fuels. The residential sector accounts for about 50% of total electricity consumption with approximately 70% of which is used for air-conditioning (AC) loads. This research investigates the role of rooftop photovoltaic (PV) systems to displace cooling loads, hence reducing residential electricity demand. Daily and annual electrical demands were monitored in a villa in Jeddah, and a range of PV systems were modelled to determine their ability to support AC and other household loads. Seasonal performance data of such systems were compared to monitored load variations to understand variability and yields. The monitored electrical demand of the villa was in the range 66-167 kWh/day which was used to estimate the required PV systems’ capacities. The results indicate that PV systems in the range 2-10 kWp present significant shortfall to support the full demand. However, a 15kWp system was found to meet the daytime total loads. These results indicate that appropriately sized rooftop PV-systems can shave-off peak air-conditioning loads. The paper discusses the importance of utilising building integrated PV in such applications in SA, and highlights the need for dissemination at scale through country wide policy framework.
Reducing emissions in London schools with photovoltaics
Authors: Godoy-Shimizu Daniel , Evans Stephen , Korolija Ivan , Humphrey Dominic , Hong Sung-Min , Simons Gareth , Schwartz Yair , Ruyssevelt Paul , Steadman Philip , Mumovic Dejan , Mavrogianni Anna 
Published: November 2021

Abstract
This paper examines the potential for PV to improve the performance of primary schools in London. Disaggregate data including energy use is compared with modelled PV generation, showing that electricity demand could theoretically be met in 59% of the schools investigated. The impact of several key factors is then considered, including architectural heritage, building age and form. The results show that the greatest PV potential exists in newer schools, as well as those that are shorter and with less dense forms.
Applying Life Cycle Sustainability Assessment to maximise the innovation potential of new technologies for critical components in wind turbines
Authors: Lam Wai Chung , Regel Sofie De , Peeters Karolien , Spirinckx Carolin 
Published: November 2021

Abstract
Future wind turbines require flexible and economically affordable product development processes to obtain reliable and validated new concepts for larger wind turbines. Pitch bearings and gearboxes are considered critical components, due to their high contribution to the operational costs of wind farms and their high failure rates. Within the Horizon 2020 project INNTERESTING (Innovative Future-Proof Testing Methods for Reliable Critical Components in Wind Turbines) new concepts and technologies concerning two critical components are being developed for future wind turbines. Life Cycle Sustainability Assessment (LCSA) is applied iteratively to gain insights in the more demanding requirements for future wind turbines, specifically on the reduction of capital and operational expenditures and improvement of the environmental and socio-economic performance aspects of wind turbines in order to reduce the economic, environmental and social impact of the newly developed technologies. This paper focusses on the results of the first LCSA iteration for the business-as-usual reference scenarios which will serve as a benchmark and reference for the newly to be developed solutions in the project.
Solar energy potential at the Great St Bernard Pass
Authors: Notzon David , Florio Pietro , Schüler Andreas 
Published: November 2021

Abstract
The historical site of the Great St Bernard Pass, situated in the Alps at an elevation of 2469 m, records very high electricity consumptions. This study aims at evaluating the photovoltaic potential at the pass. The analysis was performed on the envelope surfaces of the building complex, taking into account the topography as well as typical climate data issued from a weather station located on site. It is found that during the months from June to October, each year, 54 MWh of electricity could potentially be generated, which is more than what could be produced by the same system in the climate of Geneva.
Dynamic LCA of a single-family house, equipped with a micro-cogeneration unit, using a variable share of biomethane
Authors: Padey Pierryves , Fesefeldt Marten , Goulouti Kyriaki , Lasvaux Sébastien , Capezzali Massimiliano 
Published: November 2021

Abstract
The current study presents the CO2-eq emissions of the operational energy use of a single-family house, equipped with a micro-cogeneration unit. A back-up boiler and electricity from the grid cover the remaining energy demand, not covered by the micro-CHP. Two different technologies are evaluated, i.e. ICE and fuel cell systems, operating with a variable share of biomethane, while two different substrates were considered for the biomethane generation. A dynamic LCA was applied for the electricity mix, coming from the grid, using different time steps. The results show that producing biomethane from biowaste compared to conventional natural gas is beneficial, in terms of CO2-eq emissions, independently of the micro-CHP technology, while the total CO2-eq emissions of the fuel cell technology are higher than those of the ICE, independently of the substrate and the biomethane share.
Impact of shared battery energy storage system on total system costs and power peak reduction in commercial buildings
Authors: Skoglund Ida E. U. , Rostad Mette , Thorvaldsen Kasper E. 
Published: November 2021

Abstract
The power system is experiencing an increasing share of renewable and intermittent energy production and increasing electrification. However, these changes are creating high power peaks, are straining the grid and call for expensive investments in expansions and improvements. This paper examines how the operational strategy of shared battery energy storage systems (s-BESS) can address these issues for commercial buildings with relatively high power peaks. Due to the uncertainty in long-term costs when subject to a measured peak (MP) grid tariff, the scheduling of the battery is optimised with a receding horizon control algorithm. The optimisation model is used on a Norwegian real-life case study to find the best possible configuration with an already existing battery. Although current Norwegian regulations challenge the possibility for shared metering and billing for a s-BESS configuration, the results show that the total system cost was reduced by 19.2% compared to no battery. The community peak was reduced by 17.8% compared to no battery and 6.22-17.5% compared to individual storage, which indicates that s-BESS is of value for the DSO as well.
Implementation of machine learning techniques for the quasi real-time blind and electric lighting optimization in a controlled experimental facility
Authors: Basurto Chantal , Boghetti Roberto , Colombo Moreno , Papinutto Michael , Nembrini Julien , Kämpf Jérôme H 
Published: November 2021

Abstract
Machine Learning techniques have been recently investigated as an alternative to the use of physical simulations, aiming to improve the response time of daylight and electric lighting performance-predictions. In this study, daylight and electric lighting predictor models are derived from daylighting RADIANCE simulations, aiming to provide visual comfort to office room occupants, with a reduced use of electric lighting. The aim is to integrate an intelligent control scheme, that, implemented on a small embedded 32-bit computer (Raspberry Pi), interfaces a KNX system for a quasi-real-time optimization of the building parameters. The present research constitutes a step towards the broader goal of achieving a unified approach, in which the daylight and electric lighting predictor models would be integrated in a Model Predictive Control. A verification of the ML performance is carried-out by comparing the model predictions to data obtained in monitoring sessions in autumn, winter and spring 2020-2021, resulting in an average MAPE of 19.3%.
Non-Intrusive Luminance Mapping via High Dynamic Range Imaging and 3-D Reconstruction
Authors: Kim Michael , Tzempelikos Athanasios 
Published: November 2021

Abstract
Continuous luminance monitoring is challenging because high-dynamic-range cameras are expensive, they need programming, and are intrusive when placed near the occupants’ field-of-view. A new semi-automated and non-intrusive framework is presented for monitoring occupant-perceived luminance using a low-cost camera sensor and Structure-from- Motion (SfM)-Multiview Stereo (MVS) photogrammetry pipeline. Using a short video and a few photos from the occupant position, the 3D space geometry is automatically reconstructed. Retrieved 3D context enables the back-projection of the camera-captured luminance distribution into 3D spaces that are in turn re-projected to occupant-FOVs. The framework was tested and validated in a testbed office. The re-projected luminance field showed with good agreement with luminance measured at the occupant position. The new method can be used for non-intrusive luminance monitoring integrated with daylighting control applications.
Data-driven occupant-centric rules of automated shade adjustments: Luxembourg case study
Authors: Derbas Ghadeer , Voss Karsten 
Published: November 2021

Abstract
This study presents key findings of observed datasets in a nearly zero-energy office building for over 66 working days from June to mid-September in 2019, Luxembourg. Measurements of indoor and outdoor environmental parameters as well as user-shade override adjustments were extracted from the KNX-based building management system (BMS) in 47 office rooms located in three typical floor levels. Relative frequency and “rate of change” of blind use were analysed in terms of window orientation, occupancy level, and the time of the day. Logistic regression and data mining techniques were used to identify potentially useful and understandable occupant behaviour patterns and reveal the main triggers behind blind adjustments. The well-designed automation system together with the inner glare protection formed the base of very low user-shade interactions. A mean of 0.184 manual blind adjustments per day per office. Eight regression sub-models were developed and all were incapable of predicting user-shade lowering and raising events. Alternatively, two user profiles were mined based on 20 rules gained from clustering analysis: user (ß) was representing the passive user, and user (μ) the medium user. Overall, we conclude that the automated shading system in this building is satisfactory, user-friendly, and a robust control system.
A review of common human errors in design, installation, and operation of multiple-zone VAV AHU systems
Authors: Torabi Narges , Burak Gunay H. , O’Brien William 
Published: November 2021

Abstract
Faults in air-based heating, ventilation, and air conditioning (HVAC) systems lead to energy waste and discomfort. While the emphasis of fault detection and diagnostic (FDD) research has been on hard faults in actuators, sensors, and equipment, faults arising from human errors account for a significant portion of faults occurring in HVAC systems. In this paper, human errors occurring in air handling units (AHUs) and variable air volume (VAV) thermal zones during design, construction, and operation phases are identified through a review of the literature. Then, the faults are divided into six main categories. Based on case studies investigating these faults, the impact of each fault category on occupant comfort, energy consumption, and equipment life is discussed. The authors provide recommendations to minimize human errors in AHUs and VAV zones throughout the building life cycle.
Environmental preferences of occupants: A multi-domain approach in the Swiss open office case study
Authors: Barthelmes Verena M. , Karmann Caroline , Viviana González S. , Chatterjee Arnab , Wienold Jan , Andersen Marilyne , Licina Dusan , Khovalyg Dolaana 
Published: November 2021

Abstract
Defining indoor environmental conditions that meet the needs and preferences of occupants in open space offices can be challenging since the same space might be occupied by people with different individual needs and preferences regarding what constitutes a comfortable work environment. This study presents outcomes of a set of longitudinal point-in-time comfort surveys that were designed to capture instantaneous preference votes about momentary environmental conditions twice a day covering all four major domains of IEQ. The surveys were disseminated during two weeks across three seasons (fall, winter, summer) to 31 occupants in a Swiss open space office and supplemented with environmental data simultaneously measured in-situ at the occupant’s desk level. These surveys (up to 670 responses per environmental domain) offered insights into the discrepancies of expressed environmental preferences with respect to measured environmental conditions in open space offices.
Influence of some specific meteorological events on indoor radon dynamic in western Switzerland
Authors: Rey J , Goyette S , Palacios M , Barazza F , Gandolla M , Goyette Pernot J 
Published: November 2021

Abstract
Radon is a natural radioactive gas that may cumulate in indoor environments. The impacts of weather events on indoor radon concentration had been explored in different places around the world but only marginally in Switzerland. Using basic statistical analysis, this study investigates different meteorological parameters’ influence on indoor radon concentrations and shows that outdoor air temperature is the most influential beyond others. Finally, this paper highlights the importance of radon dynamic in buildings, a topic often overlooked by construction professionals and the broader public in Switzerland.