Commercial Building Energy Asset Score System: Program Overview and Technical Protocol (Version 1.0)

Abstract

SummaryThe U.S. Department of Energy (DOE) is developing a voluntary national energy asset score that includes an energy asset scoring tool to help building owners evaluate their buildings with respect to the score. The goal of the energy asset score is to facilitate cost-effective investment in energy efficiency improvements of commercial buildings. The system will allow building owners and managers to compare their building infrastructure against peers and track building upgrade progress over time. The system can also help other building stakeholders (e.g., building operators, tenants, financiers, and appraisers) understand the relative efficiency of different buildings in a way that is independent from their operations and occupancy.DOE's long-term goal is to ensure that there is a linked set of compatible metrics and scoring approaches that building stakeholders can seamlessly use to effectively evaluate a building's as-built and in-operation efficiencies. DOE envisions these linked scores describing various aspects of building energy performance, such as the performance of building assets, performance of building operations, and how a building compares to its peers. Given this larger vision, the energy asset score is being designed to work in concert with tools such as ENERGY STAR Portfolio Manager. Where possible, the energy asset score incorporates methods that are consistent with ENERGY STAR Portfolio Manager.Prior to beginning the energy asset score effort, DOE performed a market study to ensure that the energy asset score will help address market needs and fill identified gaps. In 2012, DOE began initial pilot testing of the energy asset score. As a result of that effort, improvements to the tool, training materials, and other aspects of the program have been made. In 2013, DOE will continue to assess the energy asset score through additional pilot testing as well as evaluations and analyses. Results from these efforts will be published in a separate document. In addition, this report will be updated periodically to reflect changes to the scoring methodology, the scoring tool, and other aspects of the program.This report outlines the technical protocol used to generate the energy asset score, explains the scoring methodology, and provides additional details regarding the energy asset scoring tool. This report also describes alternative methods that were considered prior to developing the current approach. Finally, this report describes a few features of the program where alternative approaches are still under evaluation. Energy Asset ScoreThe energy asset score enables building owners and managers to evaluate the as-built physical characteristics of buildings and overall building energy efficiency, independent of occupancy and operational choices. The physical characteristics evaluated include the building envelope, the mechanical and electrical systems, and other major energy-using equipment, such as commercial refrigeration. The energy asset score is generated by simulating building performance under...

An overview of data tools for representing and managing building information and performance data

“…A preliminary list of 24 tools was identified (Step 3 in Figure 1). These covered different phases of the building life cycle, from building design (e.g., BIM [26]) to building operation (e.g., Project Haystack, ISO standard 12655 [33,34]), and audit (e.g., BuildingSync, Asset Score [35,36]). The authors performed a preliminary analysis of these tools and categorized them into three major groups based on the hierarchical representation of building data, from the bottom up: (1) data terminology, (2) data ontologies and schemas, and (3) data platforms (databases and management tools), as shown in Figure 2.…”

“…A typology structure refers to the relative positions of spatial features, which also involves a cause-and-effect relationship between each of two elements: the source element and target element. It indicates that the target element can be triggered only by the source element, thus showing that the target element will be executed only after the source element executes (e.g., entities of the energy audit data in the web-based Audit Template [36]). An association relationship refers to the class concept, which categorizes certain elements and defines the relationships between different categories (e.g., a combination of tags to describe each building entity in Project Haystack [24]).…”

“…The asset score report includes the building's current score, the recommendations for efficiency upgrades, and its expected score after the efficiency upgrades. It also includes an assessment of individual building energy systems, and a list of data used to score the building [36]. Asset Score can import data in the BuildingSync format.…”

Standardizing Performance Metrics for Building-Level Electrical Distribution Systems

“…Although the approach is evaluated on a commercial office building, it is equally applicable to residential, industrial, or other building types. The CRBM, similar to typical commercial buildings [27], uses a three-phase AC distribution at 480Y/277V and 208Y/120V. The 480Y/277V system serves the major mechanical and lighting loads, while the 208Y/120V system serves the smaller plug loads.…”

System-level key performance indicators for building performance evaluation

“…The TSPR is implemented in the Washington State Energy Code as a performance-based compliance path for HVAC systems. It is also integrated into the U.S. Department of Energy's Building Asset Score Tool [30], which facilitates building design team's effort who wish to pursue the system compliance path.…”