Four BRT case studies have been updated: Parmenter’s Las Colinas, GSA’s Courthouse Annex and LBJ Education building (two in one combined document) and Georgia Tech’s TSRB. The case studies are also posted in the BRT training materials fileshare for use by BOMA and APPA. Additional content for the training from the case studies and material from CBEI’s building 661 have been added to the training modules.
The question, addressed by this project, is how to cost effectively save space conditioning energy and dollars in buildings with ducted constant air supply systems, particularly since many of these older central city buildings are 50% or less occupied. The problem for these older systems is how to design a low cost VAV system.
CBEI researchers worked with a local HVAC contractor to test a unique approach to this problem and determine the energy performance of a potential low cost option.
CBEI research has demonstrated through simulation that, for selected building types over a range of climate zones, HVAC package solutions exist that have the potential to provide at least 50% HVAC energy savings with a simple payback of 4 years or less.
This report is the pdf version of the CBEI Final report and results.
CBEI conducted research to develop and demonstrate a library of diagnostics decision support tools that can enable cost effective diagnostics solutions for existing buildings. This report describes early results in successfully developing and demonstrating the effectiveness of diagnostics and decision support tools for subsystem diagnostics (RTU, DX, AHU-VAV and building envelope subsystems) and fault prioritization.
A novel algorithm was tested against a large and diversified dataset comprising points from five buildings, two vendors, three distributors and more than 20K points. Overall the algorithm identifies about 90% of VAVs and 80% of AHUs and reaches an accuracy of about 90% in detecting the points required by a test application. The algorithm was incorporated into a VOLTTRON ready utility.
A fault detection and diagnostics system for rooftop air conditioners was developed using low-cost electronics. The system was designed to be compatible with the VOLTTRONTM platform. The underlying fault detection and diagnostics methodology utilizes virtual sensors to measure parts of the equipment operation that are sensitive to common faults. Using virtual sensors reduces costs while also providing accurate and reliable diagnostics.
This project implemented, validated and documented an automated system for training virtual refrigerant charge sensors for rooftop unit ACs. The system automatically tunes empirical parameters of a virtual sensor for estimating the amount of refrigerant in a system. The engineering time and costs associated with calibrating a virtual sensor are reduced because of the automated testing in an open laboratory and the reduced number of tests.
This project developed new features for the DOE SEED platform including the import, storage, and management of data from multiple sources including smart meter interval data. These added tools enable large building portfolio owners to conduct comparative analyses of their portfolios against other portfolio owners, facilitating sharing and collaboration in addition to enabling executive and operational level analyses for actionable intelligence. The enhanced platform easily support energy benchmarking and disclosure initiatives, and can increase public awareness of energy consumption and resource conservation.
This research investigates opportunities for improving building performance and occupant satisfaction through an iterative process of empirical fieldwork in green buildings and computer simulation modeling. This project demonstrates that the simulation-modeling framework is feasible and useful. Additionally, this project has generated a variety of important empirical insights about how the usability of building-level green features and social and organizational factors affect occupant and operator behavior.
A practical control algorithm for coordinating bot AC and refrigeration equipment was developed and evaluated using an energy simulation testbed for a convenience store. It was validated using actual convenience store data. The simulations allowed evaluations of savings for the unit coordinator compared to conventional control over a cooling season. The controller was designed to minimize implementation costs in that it does not require additional sensors and is self-learning.
Field demonstrations provided test and evaluation data for virtual sensor based AFDD concepts and provided a laboratory demonstration on the VOLTTRON platform.
This report presents an overview of the development of the Energy Audit Tool along with case study results from the analysis of 40 buildings, and nine audited buildings at the Philadelphia Navy Yard.
A scalable low-cost optimal chiller plant control algorithm was developed and effectively demonstrated with 128 case studies covering a variety of chiller plant load variations with each case being a weekly simulation of whole-building dynamic HVAC system models with closed loop local controls and supervisory chiller plant controls. Model-in-the-loop (MiL) analysis suggests a promising average energy saving of ~15% for medium office buildings and an average energy saving of ~10% for large hotel buildings.
CBEI developed a web-based integrated design decision support tool which utilizes energy performance data generated through coupling of whole building energy simulation models with systematic search procedures and advanced data analysis techniques. This coupling process was extended with the introduction of a simulation-based numerical optimization framework for the minimization of life cycle costs for building enclosure materials and operational energy consumption for office retrofit cases. This integrated optimization program is highly automated (thereby saving user effort) and utilizes non-commercial, open-source and readily extensible existing toolkits.