Matthias Schuss

Comparison of Simulated and Actual Energy Use of a Hospital Building in Austria

This paper compares calculated and measured energy use data (for space heating and cooling) pertaining to a hospital building in Austria. The buildings existing energy certificate as well as monitored heating and cooling demand information were acquired from the hospitals administration. Moreover, the energy performance of the building was modeled using a numeric simulation application. Thereby, an extensive effort was made to define model input assumptions (building construction, weather data, internal gains) based on actual circumstances in reality. The results of the study suggest that calculated (energy certificate) and simulated heating loads were reasonably close to actual values, whereas in case of cooling loads considerable discrepancies were observed.

Structured Building Data Management: Ontologies, Queries, and Platforms

Building data monitoring, in general, and occupancy-related data collection in particular have the potential to provide deep performance feedback for: (1) operational optimization of existing facilities and (2) improving future designs. For instance, building monitoring can support energy and performance contracting, preventive building maintenance, smart load balancing, and model-predictive building systems control. Nevertheless, currently this potential is not sufficiently realized. To address a major gap in the current practice, the present chapter first introduces an ontology for the representation and incorporation of various kinds of building monitoring data in a number of applications such as building performance simulation tools and building automation systems. Subsequently, common data processing requirements are addressed and a number of typical queries are exemplified that building monitoring data repositories must support. Finally, data repository specifications and implementations for structured collection, storage, processing, and multi-user exchange of monitored data are described.

High-Tech Solutions for Building Retrofit: Investigation of Window Systems with Vacuum Glazing

The retrofit of the historical building stock has gained significance due to energy efficiency requirements in the building sector. Major attention is drawn to windows as they are typically the building components with the highest heat transfer coefficient of the building envelope. Therefore, vacuum glazing is a potential option for improving the thermal performance of casement windows. In this context, specific considerations regarding building physics and heritage protection regulations are required.The present contribution describes the current progress of the research project VIG-SYS-RENO. New double glazing products with durable vacuum layer are emerging on the market. Such developments can be regarded as a major step toward energy-efficient windows with U-values close to conventional opaque building elements. Small thickness and excellent thermal resistance of vacuum insulation glazing renders it an attractive option in thermal retrofit of historical buildings. Vacuum glazing systems could potentially offer a feasible balance between conservation and thermal performance of windows. However, prior to any application, a set of aspects and potential issues have to be assessed and explored. These include: (i) thermal bridging effects in different joint positions, for instance the glass edge seal and the frame & wall joint; (ii) the positioning of tight layers in composite or casement windows; (iii) aspects of structural integrity of windows equipped with vacuum glazing. The present contribution structures the different aspects that need to be considered in utilization of vacuum glazing in thermal retrofit, describes applied evaluation methods, first results of the ongoing research project, and illustrates the influence of various rebate depth and length of the edge seal on thermal transmission of the window.

Monitoring of a Prototypical Free-Running Building: A Case Study in a Hot-and-Humid Climate

The provision of comfortable indoor conditions is widely considered as one of the key tasks of architecture. Hereby, different climatic regions require different concepts for the operation of buildings. Achieving thermal comfort in buildings in hot and humid regions without Air-Conditioning can be considered as a challenging task. In this context we present a monitoring study of the indoor conditions in a new prototype building, called the Zero Carbon Resort Demonstration Cottage. This building was designed according to passive cooling principles with the intent to reach a high degree of sustainability and to have little environmental impact. To explore the viability of this concept, we deployed a comprehensive monitoring of the outdoor conditions via a weather station and of the indoor conditions via air temperature and relative humidity sensors. Moreover, short-term monitoring of thermal comfort was conducted. In a first analysis step we compared the results of the indoor monitoring with the corresponding outdoor measurements. In a second step we conducted a standardized thermal comfort study. Thereby we considered the special circumstances of the thermal comfort in naturally ventilated buildings. Results suggest that acceptable indoor conditions can be maintained, if passive cooling methods are applied properly.

Building Monitoring and Diagnostics: A Web-Based Approach

Efforts toward optimized building management and operation require monitoring data from multiple sources. Experiences from previous research projects underline the need for an easily adaptable, low-cost, and easy to set up monitoring infrastructure that could provide data for modeling and performance evaluation. The increasing availability of small and powerful development boards (e.g. Raspberry Pi BeagleBoard or Arduino) facilitates the implementation of a cost-efficient infrastructure for data collection and building monitoring. For the purpose of the present contribution, the Arduino Yún was used to create a data logger that obtains data from wireless sensors, stores it locally, and syncs it with a data repository. Toward this end, we have developed a web-based user interface that enables the user to evaluate various aspects of the monitored buildings performance. The communication between the software components is implemented via RESTful interfaces and enables the user to integrate also other data sources such as web services. The paper includes an actual implementation of the above approach. Thereby, we illustrate how the constitutive system components can be integrated in terms of a versatile monitoring system with multiple utilities in terms of building performance assessment and building diagnostics.

Thermal Comfort in a Refurbished Low-Energy House: The OEKOHAUS Case Study

This contribution presents the results of a long-term thermal comfort monitoring effort in the so-called OEKOHAUS building in Petronell, Lower Austria. This building mainly acts as an educational facility for the Museum of Natural History of Vienna and includes also office and short-term occupancy spaces. It was established in an existing building, adapted and refurbished in 1996. At the time of refurbishment, it clearly exceeded the applicable standard thermal requirements for building elements. Given the buildings unique mixed use, it displays a highly fluctuating occupancy pattern. Subsequent to the recent installment of energy and indoor climate monitoring system, multiple streams of data are being collected. Specifically, indoor environmental variables relevant to thermal comfort in a number of zones in the building have been monitored and evaluated. Collected data include indoor temperature and relative humidity, which were represented and analyzed for different zones of the building in terms of psychrometric charts (for a monitoring period in Winter 2012/13). Moreover, indoor CO2 concentration was monitored to address indoor air quality conditions. The paper presents the monitoring results and their meaning within the larger context of a monitoring-based holistic building performance assessment strategy.