IBPSA2013

The current paper is concerned with a case study of a residential house, located in Ireland, which has been recently retrofitted from a conventional mixed fuel dwelling to a smart grid enabled all-electric dwelling. The aim of the specific case study is to examine the im-pact on the building retrofit measures on the dwelling carbon footprint, pre- and post- retrofit. The analy-sis was carried out using EnergyPlus.

The simulation performance gap is a discrepancy between simulated and actual performance of a building, occurring as result of differences between theoretical values in the simulation model and actual properties of and conditions in and around the building. It can be eliminated by a process of calibration of the simulation model if the simulated building exists and is being monitored. As simulations are primarily conducted in the design stage when the building does not yet exist, the calibration is not possible.

To successfully meet emissions targets and reduce energy demand in the built environment, high targets have been set for building fabric performance. However, field measurements to date have indicated that the measured as-built fabric heat loss of tested UK buildings is consistently and sometimes considerably higher than design values. Many of these results stem from co-heating tests – an in situ measurement of the heat loss across the entire building envelope.

This paper describes the development and uses of a new software program called cMap that calculates and visualizes thermal comfort parameters throughout a space and over time.      While some existing tools provide comfort calculations either over space or throughout time, cMap provides both calculations, providing a more complete picture of our thermal environment.  Since the program works as a companion to EnergyPlus, a cMap analysis can be performed quickly, fitting into existing analysis workflows.

This paper reports on the use of advanced building performance simulation in the post-graduate design studio, which explored the role and limits of analytical tools in the early stage design process. Each project began with the environmental accounting diagram technique to situate the project in its social, ecological, and economic context. Within the discovered context, performance simulations were engaged for design synthesis rather than analysis of finalized building.

This paper presents our research and development of system interfaces between Building Information Modeling (BIM) and Building Energy Modeling (BEM), for supporting integrated architectural design and energy simulation. Our methods utilize the BIM authoring tools’ Application Programming Interface (API) to translate BIM into Object-Oriented Physical Models (in Modelica) for building thermal simulation, and input files of ray-tracing software (Radiance) for daylighting simulation. Based on the methods, we have created two prototypes: Revit2Modelica and Revit2Radiance.

The potential for utilization of the building mass thermal capacity for demand side management in the residential sector is addressed. A three apartment residential houses made of massive brick, equipped with a heat pump is modeled and its thermal behavior is simulated. It is shown that thermal storage capacity of the building can indeed contribute considerably to residential demand side management activities. Even after heating periods as short as two hours the heating demand for the following four hours can be reduced by almost 20 %.