Live Energy Trnsys – Trnsys Simulation within Google Sketchup

With the current focus on energy performance certification, factors such as increased and unstable fuel prices and consequent heating and electrical costs as well as the large number of buildings that are going to require energy analysis, a real need has surfaced for powerful, fast, and easy to use energy analysis solutions that will not be limited to energy experts. Live Energy (formerly called Demeter) [Finlayson et al, 2008], an energy analysis plug-in for Google's SketchUp utilises the SketchUp application programming interface and rich internet technologies to integrate into the SketchUp environment and make the process of building energy analysis as simple as possible. Live Energy builds a rich energy framework around the SketchUp building model, which can be sent to an accompanying energy analysis engine or be exported for use with other tools. TRNSYS is a powerful transient systems simulation environment that allows for the creation of component-based models to represent energy systems (including localised weather, equipment, building structure etc.) based on real life scenarios and then to calculate various outputs based on the user's requirements. Due to a steep learning curve and a complex user interface for inputting building data, TRNSYS has long been the domain of academics and building services engineers. This paper outlines an attempt at simplifying entry to the TRNSYS environment while still maintaining a degree of control for advanced users. The TRNSYS extension to Live Energy allows for the generation of a TRNSYS Multi-Zone building (Type56) component from a Google SketchUp model and will create an executable TRNSYS simulation that can be run directly from Google SketchUp, thereby combining the power of the TRNSYS simulation environment with the simplicity and ease of use of Google SketchUp. INTRODUCTION In a time of volatile fuel and material costs and a growing awareness of environmental issues, it is becoming imperative to those planning and constructing buildings to be aware of the energy performance of buildings throughout the life cycle – from conceptual design to building maintenance. In addition, with the introduction of the European Union Energy Performance of Buildings Directive (EPBD) [DIAG, 2009] it is now necessary for all building owners to analyse and produce energy performance certificates for their buildings. With this huge increase in the demand for energy performance analysis, various software tools have been developed to analyse different aspects of a building's energy performance. These substantially differ in analysis complexity. For example, some tools analyse a building with the aim of generating an energy performance certificate while others simulate a building's energy systems in detail and provide various outputs depending on the needs of the user. Many energy analysis tools require a building model to be created specifically for that tool, often graphically but sometimes via text input. With the vast number of energy analysis tools available and with their varying capabilities, it is often desirable to use more than one tool in a building project to acquire a more complete picture of performance. This can, however, be extremely time-consuming as a new model of the building may need to be created for each analysis tool, which may not match exactly due to user error or the limitations of the modelling software.