| dc.description.abstract | Buildings consume more than 40% of the primary energy produced globally, making them the leading contributors to climate change and global warming. Effectively reducing building energy is essential to reduce its energy footprint, mitigate climate change, and achieve sustainable development goals for climate action and sustainable cities. Building energy comprises embodied, operational, and end-of-life (EOL) energy. In modern buildings, operational energy accounts for 80–90% of the total energy consumption over its lifecycle. Operational energy in buildings thus carries the largest potential for reduction in energy consumption and consequent reduction in emissions. Buildings increasingly rely on sensors to reduce energy consumption, specifically pertaining to occupancy. As a result, the integration of energy-saving sensors has emerged as a focus area for lowering operational energy in buildings.
Sensing and control systems (SCS) are essential components of modern buildings that perform various functions, such as switching appliances, monitoring occupants, measuring indoor parameters, etc. Energy-saving sensors are often employed to reduce energy consumption by switching or regulating appliances (e.g., lights, HVAC) in response to usage and occupancy. However, the life-cycle energy and resources associated with the sensors (SCS) should be considered in estimating the potential energy-saving in buildings. It is crucial to account for the sensors’ energy footprint in a building’s lifecycle energy assessment. Energy neutrality is a holistic approach that considers the entire lifecycle of the sensor-integrated building. The current study (thesis) proposes a novel energy neutrality framework to examine the effective integration of energy-saving sensors in a building.
Efficiency-based approaches for building-energy reduction have been linked to multiple rebound effects, wherein despite efficient utilisation of energy, the net energy consumption of the building goes up. Hence, it is necessary to adopt an effectiveness-based approach when assessing and reporting the performance of energy-saving sensors. Effectiveness refers to the degree to which a process, system, or intervention achieves its goals. It measures how a sensor performs in achieving the desired outcomes of reducing building operational energy while also minimising the lifecycle energy of the sensor-building system. In this dissertation, the concept of energy neutrality has been adopted to examine the effectiveness of sensor integration in the building by accounting for the lifecycle of the sensor and the accruing energy reduction by its usage. Assessing the effectiveness of integrating sensors in buildings is critical to determine the energy neutrality of the overall building-sensor system.
This study develops and tests the integrated energy neutrality framework (iENF) to achieve these objectives. This framework comprises three components or subsystems: the building, sensing and control system, and occupancy. The interactions between these subsystems have been studied to examine the effectiveness of integrating energy-saving sensors in the building. For the Energy Neutrality Assessment, three indicators have been identified: the Energy Neutrality Index (ENI), Energy Recovery Time (ERT), and Gram per Wattage Ratio (GpW).
A detailed implementation methodology, including Energy Neutrality Mapping (ENM) and simulation, has been adopted to test the proposed framework. The simulation system relies on three main components: a) Lifecycle Energy Assessment (LCEA), b) Building Energy Modelling (BEM), and c) Occupancy monitoring. This methodology has been adopted for institutional and office buildings. Two case studies from Bangalore, India, and one from Gainesville, Florida, have been examined. The first case study is a multistorey office building in southern Bangalore; the second is an advanced nano-fabrication cleanroom facility in Bangalore; the third is a single-storied office-cum-laboratory modular building in Gainesville. Several scenarios have been examined for their impact on the overall energy neutrality of the sensor-building system. Firstly, the framework has been evaluated for various climate zones and building orientations. Secondly, different sensor typologies, connectivity, and connected loads have been examined. Finally, the impact of occupancy on energy neutrality has also been discussed. With the help of the selected case studies, the integrated Energy Neutrality Framework (iENF) has been successfully tested. The iENF has the potential to be adopted for smart/intelligent buildings, providing designers, architects, and engineers valuable information for effectively integrating diverse sensors into buildings. | en_US |
