18 Février – Thesis defense - Catalina Giraldo Soto
09 h Bilbao Engineering School - University of the Basque Country (UPV / EHU)
Optimized monitoring techniques and data analysis development for in-situ characterization of the building envelope`s real energetic behaviour.
The general objective of this doctoral thesis project is to advance in the reliability and optimisation of Monitoring and Control Systems for HLC estimation and decoupling, in order to be able to define a minimum energy Monitoring Kit for residential or tertiary buildings in the future. These monitoring kits should be as unobtrusive as possible and should allow the minimum amount of data to be reliably monitored which, together with a correct analysis, should allow the real behaviour of the building envelope to be characterised.
Thus after presenting the existing in-use HLC estimation and decoupling methods, the analysis of the State of the Art on monitoring and control systems for in-use building envelope energy characterisation is performed. Thanks to this review on monitoring and control systems analysis, it has been found that the overall uncertainty of indoor and outdoor temperature (when presented) is always considered to be the manufacturer’s accuracy in the existing literature. Using only the manufacturer accuracy as the overall uncertainty for these two important measurements required for the in-use HLC estimation, might lead to strongly underestimating their real uncertainty and this underestimation would be propagated to the estimated HLC values. To deeply analyse this topic, which could generate serious reliability issues for the estimated HLC values, a three dimensional monitoring system has been designed and deployed in an office building. To analyse the overall uncertainty of the indoor air temperature measurement, four thermal zones within the office building have been monitored with a three dimensional approach. To analyse the overall uncertainty of the outdoor air temperature measurement, a three dimensional monitoring approach has also been implemented around the building envelope.
Furthermore, the results of this analysis have allowed the identification of the best location for the indoor and outdoor temperature sensors on the monitored building. Besides, the quantification of the discrepancies between the value of the sensor accuracy given by the manufacturer and the experimental value of the sensor accuracy plus the monitoring and control system has also been analysed. Here, the main contribution of this thesis can be found: the methodology developed to allow the quantification of the overall uncertainty of intensive variable measurements such as indoor air temperature and outdoor air temperature on in-use buildings. This methodology not only allows us to obtain the overall value of these measurements’ uncertainty containing all sources of uncertainty (called Measurement Uncertainty), but also allows us to decouple the Measurement Uncertainty into the uncertainty associated to the random and systematic errors. This decoupling separates the value of the variance associated with the overall uncertainty into the sum of two variances, one variance associated with the uncertainty related to the systematic errors (called in the study, Sensor Measurement Uncertainty) and another associated with the uncertainty related to the random errors (called in the study, Measurement’s Spatial Uncertainty).
On the other hand, from the analysis of the Co-heating and Average method to estimate the HLC, an extremely detailed monitoring system has been designed and implemented in a residential building. The aim of this extremely detailed monitoring system is to be able to analyse what the minimum required set of sensors to estimate and decouple the in-use HLC values with a sufficient reliability. The selected sensors have the greatest possible accuracy that could be found for building sector applications. A detailed economic analysis is also included for this extremely detailed monitoring.