The Energy Independence and Security Act of 2007 established a national goal of achieving net-zero energy buildings by 2030. Approximately 84% of the life cycle energy use of a building is associated with operating the building rather than the materials and energy used for construction [1]. This program will provide the measurement science to realize energy efficient building operation through integrated cybernetic building systems with distributed, embedded intelligence that can optimize building system performance, detect and respond to faults and operational errors, and enable integration of building systems with smart grid technologies.
What is the problem?
"The world is facing twin energy related threats: that of not having adequate and secure supplies of energy at affordable prices and that of environmental harm caused by consuming too much of it" [2]. Any successful response to these threats must consider buildings. Buildings account for 40% of the United States' energy use and a similar percentage of carbon dioxide emissions, more than the transportation or industrial sectors [3]. Emissions associated with buildings and appliances are projected to grow faster than those from any other sector. In order to ensure adequate supplies of energy and to curtail the projected growth of CO2 emissions, it is essential that building energy consumption be significantly reduced. The Energy Independence and Security Act of 2007 established a national goal of achieving net-zero energy buildings by 2030.
Approximately 84% of the life cycle energy use of a building is associated with operating the building rather than the materials and energy used for construction [2]. "Building systems almost never achieve their design efficiencies at any time during building operation and their performance typically degrades over time" [5]. As the Nation proceeds with developing a new smart grid and increasing the use of intermittent renewable energy sources, buildings occupants will need access to actionable energy consumption information and building systems will need to become collaborative partners in maintaining the stability and reliability of the grid.
In addition to energy issues, building operation practices face pressure to improve safety, security, and occupant comfort and health. Building control companies, equipment and system manufacturers, energy providers, utilities, and design engineers are under increasing pressure to improve performance and reduce costs by developing building systems that integrate more and more building services, including energy management, fire and security, vertical transportation, fault detection and diagnostics, optimal control, the real time purchase of electricity, and the aggregation of building stock. Measurement science is lacking to enable these systems to have the intelligence to communicate, interact, share information, make decisions, detect and respond to faults, and perform in a synergistic and reliable manner. Specific needs include standard data models, communication protocols, user interface standards, security procedures, testing tools, and performance metrics. Overcoming these barriers is critical if building systems are to meet these operational needs and if the U.S. is to obtain a significant share of the developing world wide market for such systems.
What is the technical idea?
The new idea is to address the measurement science needs of cybernetic building systems in a holistic, integrated manner that considers complex system interactions and their impact on energy consumption, comfort, safety, and maintenance. Measurement science is needed that will:
- Lead to enhancements in communication protocol standards that enable the practical use of integrated HVAC, lighting, security, vertical transport, energy management, and emergency response systems to achieve increased comfort, safety, and energy efficiency;
- Be used to create a laboratory testbed capable of whole building emulation of normal operation and a variety of faulty and hazardous conditions suitable for evaluating the needs and performance of cybernetic building systems in identifying and responding to equipment failures and abnormal conditions;
- Enable more energy efficient building operation through development of information models and software tools that improve the design and commissioning process and embedded intelligence in building control systems that can detect and respond to problems and optimize the control and performance of building systems; and
- Enable secure real-time communication of building system information to outside parties such as interconnection of building automation and control systems with a future smart utility grid.
What is the research plan?
The research plan consists of a portfolio of interrelated projects that focus on key areas of measurement science needed to achieve successful development and implementation of cybernetic building systems. Collectively they provide a comprehensive approach that will lead to new industry standards and practices which will result in a radical market transformation in building system design and operation. The Smart Building Automation and Control Testbed and Standards project is the cornerstone upon which other aspects of the research program are built. It supports ongoing development and refinement of a unique laboratory facility, the Virtual Cybernetic Building Testbed (VCBT). This realistic, whole-building emulator is used by other projects in the program to conduct research under controlled conditions that cannot be accomplished in actual buildings. This project also provides technical support for the ongoing development of key enabling standards that create the communication infrastructure used in the VCBT and upon which embedded intelligent systems will be built. EL's past work has led to international adoption and commercialization of BACnet, one of the most widely used and successful standards in ASHRAE history. In FY 2016, EL will continue work with industry partners to enhance BACnet capabilities in ways that eliminate barriers to extending BACnet beyond HVAC applications and enable BACnet systems to provide operational data to enterprise management tools. Some of the older hardware infrastructure for the VCBT will be replaced to ensure continued operation of the facility and increase the flexibility of use. New standard sequence of operations will be implemented in both the building controllers and the supporting building simulation to support testing of automated commissioning tools. The HVACSIM+ user interface will be updated to make it easier to develop simulations for different building configurations. Commissioning Building Systems for Improved Energy Performance is a project intended to address the problem that building automation systems are rarely commissioned and are poorly maintained, resulting in excessive energy consumption and other operational issues. The commissioning research builds on past international collaborations through the International Energy Agency and will focus in FY 2016 on expanding the capabilities of the NIST HVAC-Cx commissioning tool by developing automated test scripts for verifying that control systems correctly implement ASHRAE standard sequences of operation and by determining the effectiveness of these tests using both the VCBT and field trials. A method will also be developed to characterize the impact of faults on energy consumption and occupant comfort in order to guide users in prioritizing their maintenance activities and repairs. Two projects address automated fault detection and diagnostics (FDD) for HVAC system components. One focuses on residential systems and one on commercial building systems. Both projects involve developing and testing FDD tools that can be implemented using commercially available instrumentation and control products, and demonstrating the energy benefits of detecting and responding to faults before building conditions degrade to the point that occupants complain. In FY 2016 the work will focus in the residential area on testing the NIST-developed adaptive FDD algorithm under real-world transient conditions, laboratory tests to collect well-characterized system performance data under multiple simultaneous faults, and continuing technical support for ASHRAE SPC 207P. For commercial building systems, the work will focus on collaborating with CRADA partners for continued field testing of a Fault Detection and Diagnostic – Expert Assistant (FDD-EA) in HVAC and compressed air system applications, expanding the interactive diagnostic capabilities of the tool, and developing a way to prioritize faults based on energy impact and occupant comfort. A research project on control optimization using intelligent agents seeks to enable a fundamental paradigm shift in the way in which building system operation is optimized for energy efficiency. Classical optimization techniques have not been successful in buildings but adapting intelligent agent technology from other fields offers the promise of significant improvement in building operations. In FY 2016 the work will focus on commissioning and characterizing the measurement capability of a new laboratory facility for testing intelligent agent-based optimization approaches using real building mechanical equipment, and the development of a simulation model of the laboratory facility. Cybernetic building systems involve communication and interaction with entities outside the building as well as within. In FY 2016 the Building Integration with the Smart Grid project will continue improving and expanding consumer access to their energy usage information in the White House Green Button initiative, lead an industry Transactive Energy Challenge to develop computer simulation packages for exploring the viability of a range of transactive energy scenarios, continue activities that support the development of key standards for building-to-grid integration identified in the NIST Smart Grid Roadmap, and also conduct research expected to result in new control strategies for building electrical load management that is responsive to needs of the smart grid.