Estimation of the Heat Loss Coefficient of Two Occupied Residential Buildings through an Average Method

The existing performance gap between the design and the real energy consumption of a building could have three main origins: the occupants’ behaviour, the performance of the energy systems and the performance of the building envelope. Through the estimation of the in-use Heat Loss Coefficient (HLC), it is possible to characterise the building’s envelope energy performance under occupied conditions. In this research, the estimation of the HLC of two individual residential buildings located in Gainsborough and Loughborough (UK) was carried out using an average method. This average method was developed and successfully tested in previous research for an occupied four-story office building with very different characteristics to individual residential buildings. Furthermore, one of the analysed residential buildings is a new, well-insulated building, while the other represents the old, poorly insulated semidetached residential building typology. Thus, the monitored data provided were filtered in order to apply the abovementioned average method. Even without fulfilling all the average method requirements for these two residential buildings, the method provides reliable HLC values for both residential buildings. For the house in Gainsborough, the best estimated HLC value was 60.2 W/K, while the best approach for Loughborough was 366.6 W/K. Thus, despite the uncertainty sources found during the analysis, the method seems promising for its application to residential buildings.This work was supported by the Spanish Ministry of Science, Innovation and Universities and the European Regional Development Fund through the MONITHERM project “Investigation of monitoring techniques of occupied buildings for their thermal characterization and methodology to identify their key performance indicators”, project reference: RTI2018-096296-B-C22 and -C21 (MCIU/AEI/FEDER, UE)

Monitoring System Analysis for Evaluating a Building’s Envelope Energy Performance through Estimation of Its Heat Loss Coefficient

The present article investigates the question of building energy monitoring systems used for data collection to estimate the Heat Loss Coefficient (HLC) with existing methods, in order to determine the Thermal Envelope Performance (TEP) of a building. The data requirements of HLC estimation methods are related to commonly used methods for fault detection, calibration, and supervision of energy monitoring systems in buildings. Based on an extended review of experimental tests to estimate the HLC undertaken since 1978, qualitative and quantitative analyses of the Monitoring and Controlling System (MCS) specifications have been carried out. The results show that no Fault Detection and Diagnosis (FDD) methods have been implemented in the reviewed literature. Furthermore, it was not possible to identify a trend of technology type used in sensors, hardware, software, and communication protocols, because a high percentage of the reviewed experimental tests do not specify the model, technical characteristics, or selection criteria of the implemented MCSs. Although most actual Building Automation Systems (BAS) may measure the required parameters, further research is still needed to ensure that these data are accurate enough to rigorously apply HLC estimation methods.This work was supported by: Spanish Economy and Competitiveness Ministry and European Regional Development Fund through the IMMOEN project: "Implementation of automated calibration and multiobjective optimization techniques applied to Building Energy Model simulations by means of monitored buildings". Project reference: ENE2015-65999-C2-2-R (MINECO/FEDER); European Commission through the A2PBEER project "Affordable and Adaptable Public Buildings through Energy Efficient Retrofitting". Grant agreement No.: 609060; Laboratory for the Quality Control of Buildings (LCCE) of the Basque Government; University of the Basque Country (UPV/EHU). Framework agreement: Euro-regional Campus of Excellence within the context of their respective excellence projects, Euskampus and IdEx Bordeaux. Funder reference: PIFBUR 16/26

Decoupling the heat loss coefficient of an in-use office building into its transmission and infiltration heat loss coefficients

[EN]The actual building energy performance essentially depends on the building occupant's behaviour, the real performance of the installed energy systems and the in-use performance of the building envelope. The thermal performance characterization of in-use building envelopes, based on monitored data, represents a crucial step towards bridging the gap between the designed and as-built energy performance of buildings. The main indicator to analyse the performance gap of building envelopes is the Heat Loss Coefficient (HLC); when measured, it commonly shows considerable differences when compared with the design value. This research goes further and proposes a method, based on monitored data from in-use buildings, for the decoupling of the HLC of in-use buildings into its transmission (UA) and infiltration (C-v) heat loss coefficients, in order to identify the origin of the heat losses. The identification of this origin will facilitate the reduction of the performance gap. Therefore, a multi-storey occupied office building of the University of the Basque Country has been monitored and analysed, where the in-use HLC for each floor and for the whole building have already been estimated using an average method. Then, based on the ASTM D6245-18 Standard, the decay method of the metabolic CO2 of the building's occupants has been successfully applied in this paper to obtain the Air Change per Hour (ACH) rates due to infiltrations. These ACH values have been used to decouple the estimated HLC values into their transmission and infiltration parts.This work was supported by the Spanish Ministry of Science, Inno-vation and Universities and the European Regional Development Fund (grant number RTI2018-096296-B-C22) through the MONITHERM project 'Investigation of monitoring techniques of occupied buildings for their thermal characterization and methodology to identify their key performance indicators', project reference: RTI2018-096296-B-C22 (MCIU/AEI/FEDER, UE) . The corresponding author also acknowledges the support provided by the Education Department of the Basque Gov-ernment through a scholarship granted to her to complete her PhD degree

Estimating and decoupling the Heat Loss Coefficient of in-use buildings into its Transmission (UA) and Infiltration and/or Ventilation (Cv) heat loss coefficients through basic monitoring and modelling

270 p.A través de esta Tesis, se ha podido desarrollar un método preciso basado en datos medidos para estimar resultados fiables del coeficiente de perdida de calor para edificios en uso, que después se desacoplan en el coeficiente de pérdida de calor por transmisión e infiltración y/o ventilación. Este trabajo será de gran ayuda a la hora de identificar el origen de las pérdidas de calor, y así, poder comprender mejor la brecha de rendimiento energético que existe en los edificios. Para ello se han utilizado tres casos de estudio con diferentes características: una caja de estudio llamada ¿Round Robin box¿ que simula un edificio a pequeña escala, dos edificios residenciales en uso y un edificio de oficinas ocupado