Research performance benchmarks

As part of setting a project's performance goals, start by researching performance benchmarks for similar building types. This often focuses on benchmarking site energy use intensity (EUI) but may also consider other metrics such as source energy, carbon emissions, energy cost, and others.

Benchmarking is the comparison of measured performance of a building to its peers, or established norms, with the goal of informing and motivating performance improvement. Benchmark data sources may be either collected from real buildings, or based on modeled simulations of a reference building built to a specific standard (such as an energy code).

For existing buildings, benchmarking can measure operational performance and compare a facility's energy use to similar facilities to assess opportunities for improvement, and quantifying/verifying energy savings. Many local ordinances exist throughout the country that require building owners to disclose energy performance data.

For the design of new buildings or major renovations, reviewing benchmark data sources can help to define project energy goals. This page discusses the data sources and how they may be used to set performance goals and targets.

The 2030 Challenge Benchmark

Zero tool - example benchmarking analysis results

Architecture 2030 issued The 2030 Challenge in 2006 asking the global architecture and building community to adopt the following targets:

• All new buildings, developments and major renovations shall be designed to meet a fossil fuel, GHG-emitting, energy consumption performance standard of 70% below the regional (or country) average/median for that building type.

• At a minimum, an equal amount of existing building area shall be renovated annually to meet a fossil fuel, GHG-emitting, energy consumption performance standard of 70% of the regional (or country) average/median for that building type.
• The fossil fuel reduction standard for all new buildings and major renovations shall be increased to:
  • 80% in 2020
  • 90% in 2025
  • Carbon-neutral in 2030 (using no fossil fuel GHG emitting energy to operate).

In order to help design teams meet these goals, a benchmarking tool called Zero Tool was developed. The Zero Tool asks the user to provide information about the building's location, type (e.g. office, school, etc.), anticipated hours of operation, and a few other factors. These inputs will provide a benchmark value for an "average building" as well as a target EUI to achieve the percentage reduction targets called for in the 2030 Challenge. Results include site energy EUI, source energy EUI, and GHG emissions. Detailed instructions for using the Zero Tool are provided in their User's Guide.

The American Institute of Architects utilizes an EUI target setting and tracking system called the 2030 Commitment, based on the methodology employed by the 2030 Challenge. The AIA 2030 Commitment has led to many architecture firms benchmarking and tracking the EUI of their designs, and this information is collected annually by AIA in a database system called the Design Data Exchange (DDX). AIA publishes an annual report called 2030 Commitment by the Numbers tracking and sharing this data.

The Building Performance Database (BPD)

Building Performance Database - example benchmarking analysis showing the distribution of site energy use intensity of administrative office buildings data. The vertical line with a value in the "bubble" indicates the median EUI value.

The Building Performance Database (BPD) is the largest publicly-available source of measured energy performance data for buildings in the United States. It contains information about the building’s energy use, location, and physical and operational characteristics. The BPD can be used by building owners, operators, architects and engineers to compare a building’s energy efficiency against customized peer groups, identify energy efficiency opportunities, and set energy efficiency targets. It can also be used by energy efficiency program implementers and policymakers to analyze energy efficiency features and trends in the building stock. The BPD compiles data from various data sources, converts it into a standard format, cleanses and quality checks the data, and provides users with access to the data in a way that maintains anonymity for data providers.

The BPD consists of the database itself, a graphical user interface allowing exploration of the data, and an application programming interface allowing the development of third-party applications using the data.

The graphical user interface allows for creating different types of graphs, charts, and tables of data. Users can select building type(s), locations, and filters by size, occupant type (e.g. administrative office vs. medical office), types of design features (e.g. HVAC system type), and many others. Data can be presented in terms of site energy use intensity, source energy use intensity, GHG emissions, energy by fuel type, and even other metrics such as number of LEED points achieved. This high level of customization of the benchmarking data can provide the user with a detailed understanding of how different variables impact energy performance.

Prototype Building Models

Prototype models represent a range of different building types, modeled to minimally meet the energy code requirements. Different versions of the models exist for each climate zone, and for different versions of the energy code (ASHRAE 90.1, and IECC).

Because these models are modeled to the code requirements, they often have similar characteristics to a "baseline" model used for code compliance analysis. This baseline may serve as a good benchmark as it gives an indication of an EUI value that must be met to meet code. Often times, project performance goals are specified as a % better than code target. While the prototype is indicative of a code-minimum EUI, it must be understood that the rules for creating a project-specific code baseline model are more complicated and therefore the code baseline EUI will not match the prototype model EUI exactly. But, nonetheless, in the early stages of a project, the prototype EUI is quite useful in that it is a known value that doesn't require any modeling to determine.

The Department of Energy and Pacific Northwest National Laboratory generate prototype models for each update to the national model energy codes and make them freely available online.

For each building type and code vintage, a Microsoft Excel spreadsheet "scorecard" is available that summarizes the key input parameters of the model. Additionally, input files for the models in EnergyPlus IDF format are available. The simulation results for each building type/climate zone are summarized in the EnergyPlus output results tables. Unfortunately (for energy modelers in the United States), these EnergyPlus output tables are presented in Metric (SI) units. However, the IDF files can be rerun to generate the results tables in I-P units by changing a single parameter in the IDF file. This may be useful if you plan to dig into the details of the simulation results.

For the sake of benchmarking, it is probably not necessary to re-run models and convert units because PNNL provides detailed EUI tables (in I-P units) that can be easily navigated by building type, code vintage, and location. These results are available in spreadsheet format, and also using an online data visualization tool called Tableau. To use the Tableau tool, select the tab "End-Use by Code," and then you can view performance data in a range of metrics including site energy, source energy, energy cost index, carbon emissions, and energy by fuel type. Results can be filtered by climate zone(s), building type(s), and code vintage(s). Data exists for ASHRAE Standard 90.1 code vintages dating back to 2004.

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  Example of the medium office prototype model scorecard

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  Example of prototype model results visualization using the online Tableau tool.

CBECS

The Commercial Buildings Energy Consumption Survey (CBECS) is a national sample survey that collects information on the stock of U.S. commercial buildings, including their energy-related building characteristics and energy usage data (consumption and expenditures). Commercial buildings include all buildings in which at least half of the floorspace is used for a purpose that is not residential, industrial, or agricultural. By this definition, CBECS includes building types that might not traditionally be considered commercial, such as schools, hospitals, correctional institutions, and buildings used for religious worship, in addition to traditional commercial buildings such as stores, restaurants, warehouses, and office buildings.

CBECS data is presented in reports and tables. The tables provide a detailed summary of the building data collected and allows for analyzing the data by a number of parameters such as building type, size and location, but also allowing analysts to drill down to very specific details such as analyzing the EUI of buildings based on when they were built; whether occupied by the owner vs. rented; EUI of a building type based on construction types, installed system types, operational characteristics, and many other useful factors.

CBECS data is collected on a semi-regular basis, with the most recent survey having occurred in 2018. The tables below can be accessed by visiting the data section of the site, selecting the version of CBECS data (i.e. the year in which the survey occurred), and then selecting the "consumption & expenditures" tab of the data page. The tables below are the "end-use consumption" tables for all fuels, but additional tables are available for looking at individual fuel types such as electricity or natural gas. Tables are available in pdf or spreadsheet format.

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  CBECS data table with overview level of information - EUI by building type and vintage

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  CBECS data table with detailed level of information - EUI by building design characteristics

CEUS

A California-specific survey of existing buildings called the California End-Use Survey was performed in 2006. Unfortunately, this data appears to have been removed from project website although it appears that various 3rd parties have posted PDFs of the project report online (can be found by googling but not linked here since it is not an original source).

CalBEM Benchmarking Tool

Example output of the CalBEM benchmarking tool

CalBEM is a California Investor Owned Utility (IOU) sponsored initiative focused on improving the use of BEM to help achieve the state's energy goals. CalBEM has created an online tool for benchmarking projects in California. Users of the tool select a building type, vintage of the California energy code (Title 24) and climate zone and are presented with charts that show energy consumption by each end use in terms of site energy, emissions, and TDV energy. Data can also be exported in spreadsheet format.

Additional Resources

• Interactive maps for energy benchmarking data, programs, and policies - EnergyStar's lookup tool for finding information about benchmarking programs around the country
• Ten Key Building Energy Metrics - An article from IES's blog discussing commonly used metrics for assessing energy performance
• Energy Benchmarking and Transparency Benefits - An informational guide published by the Institute for Market Transformation (IMT) that is a primer explaining what benchmarking is, how to do it, and its benefits.
• Building Energy Benchmarking - DOE's webpage on benchmarking focused on state and local governments who may wish to put benchmarking programs together.

Links to external websites are provided as a convenience for further research, but do not imply any endorsement of the content or the operator of the external site, as detailed in BEMcyclopedia's general disclaimers.