ID#2097 made on
EAc5 - Measurement and verification
LEED BD+C: New Construction, LEED BD+C: Schools, LEED BD+C: Core and Shell
Our team wishes to submit an alternate approach to EAc5 consistent with the intent to "provide for the ongoing accountability and optimization of building energy and water consumption performance...
Our team wishes to submit an alternate approach to EAc5 consistent with the intent to "provide for the ongoing accountability and optimization of building energy and water consumption performance over time." We'd like to use the PACRAT (Performance Assessment and Continuous Recommissioning Analysis Tool) automated Fault Detection and Diagnostic (FDD) program to provide ongoing M&V analysis. PACRAT utilizes recorded system operational data to improve facility operations and planning by: 1) Diagnosing system problems and poor performance and identifying energy wastes; 2) Documenting important system operational parameters such as loads, energy use, indoor air quality, etc.; 3) Setting a new standard for Monitoring and Verification of energy uses; and 4) Summarizing and formatting the data for effective visualization. PACRAT integrates enterprise data from many different controls, monitoring and metering systems. The system fully puts to use the volumes of data that can be obtained from building control systems, meters and data loggers, which generally gets ignored and lost. Benefits include: Actionable Results: PACRAT provides detailed, quantifiable, and actionable results of suboptimal and problem building and system performance. Output exceeds EAc5 goals by identifying the systems that are not functioning as expected and telling specifically how to correct it. With Option D modeling approach, the expense of developing, calibrating, and repeatedly running these models provides little lasting operational value to the performance of the building. Discrepancies in actual vs. modeled performance typically require extensive field investigation and trend data analysis to determine the cause(s) of the off-baseline performance. Persistence: Once configured, PACRAT provides regular (quarterly) output of system anomalies and performance results. Reviews of projects awarded EAc5 using the Option D approach indicates that the 'calibration' exercise is often not performed. When it is performed, the nature of the procedure is to vary the input parameters of the building model until they come close to matching actual performance, often with only a cursory analysis of building systems to identify any inefficiencies. Makes Use of All Systems Data: PACRAT exceeds the 'Option D' approach by using virtually all input/output data for each system under analysis (including individual sensors, valve and damper outputs, setpoints, etc.). In this way, it can perhaps be viewed as a pervasive 'Option B' approach, where most of the parameters of each system are analyzed down to the individual control loop level. Analysis extends down to the individual systems level and includes air handling units, chillers, and hydronic pumping systems. Automated: Truly automated FDD methods remove the need for human beings to be contracted and engaged to provide analysis. The computational engine replaces the need for people to interpret results and is more efficient and can provide for more cost-efficient analysis. Web-Based: PACRAT is a web-based, electronic process from start to finish. Data is trended by the building automation system and is transmitted to the computational engine for analysis. Results are provided in a database format for the user to access via the Internet. The database format provides results that are filterable and searchable. Action taken by the Owner can also be entered onto the database for future reference. This project will include the electrical submetering points required by Credit 5, and will also include thermal (Btu) metering of chilled and hot water loads. Additionally, PACRAT will use approximately 400 system input/output points, including temperatures, humidity, pressures, status, damper commands, valve commands, and most setpoints perform the fault detection and diagnostics results and performance graphs. We propose an alternative compliance path requiring continuous metering equipment for those end-uses currently required by EAc5, as well as an automated FDD tool with quarterly reporting. This strategy will provide much more valuable feedback to the building operator and allow for ongoing accountability and optimization of building energy and water consumption performance over time. We are confident this will result in a more efficiently operated building with the highest level of accountability for systems performance.
Based on the description of the proposed alternative compliance path for EAc5, it does not appear that the PACRAT and FFD systems by themselves would meet the requirements of the credit. While the described software and technology appear to provide sophisticated capabilities to capture, trend and analyze energy related data, the data must be reconciled to the energy and water performance projections generated under EAp2/c1 and WEcx as per the the requirements of EAc5 and pertinent sections of IPMVP Vol 1, 2001.
Related Addenda (Corrections & Interpretations)