Modelling and performance evaluation of net zero energy buildings

Developing a design philosophy to reduce carbon emissions from the built environment is a major motivator for the formation of the net zero energy concept. For net zero energy buildings to be widely adopted, a deeper understanding of the drivers of their success is needed, as well as their comparative differences and similarities to buildings of more conventional design. This thesis investigates the effects of different building design and operation principles in relation to net zero energy buildings. Simulations of three case study buildings (two of which are designed to be net zero energy) were performed to identify the building design and operation elements which contribute most to energy efficiency.\nThrough development and validation of building models of both net zero and conventional designs in this thesis, it was found that validation of smaller, more energy efficient building models can present challenges less commonly encountered in models of more conventional buildings. An understanding of the sensitivities of net zero energy buildings to alterations in design and specification were gained. Results show that net zero energy buildings are more sensitive to changes such as glazing type, and HVAC setpoint based on the case studies presented.\nThis thesis has looked at quantifying the contribution of different building elements and systems to overall energy savings via simulation. The net impact of different glazing types, lighting control methods, window shading schedules, and HVAC set points on overall building energy consumption were examined.\nThis thesis also reports on the net zero energy balance for one case study building. Results show that the building was net positive for the 12-month period considered. Both energy imported/exported and energy generated/consumed were considered, as well as the load matching, grid interaction, and some preliminary analysis of power quality factors. These power quality factors and their relationship with net zero energy buildings must be understood before the net zero concept can be widely adopted.