ComStock Analysis Tool

ComStock™ allows stakeholders to better understand how the commercial building stock uses energy and assess how technologies and demand-side management strategies can improve that energy use pattern in the future.

City skyline in the evening.

ComStock is a U.S. Department of Energy (DOE) model of the U.S. commercial building stock, developed and maintained by NREL. The model uses a sample of building characteristics from DOE's Commercial Prototype Building Models and Commercial Reference Building. Unlike many other building stock models, ComStock combines these with a variety of additional public- and private-sector datasets. Collectively, this information provides high-fidelity building stock representation with a realistic diversity of building characteristics.

ComStock logo

Understanding how large groups of commercial buildings use energy throughout the day is a challenge. Individual buildings can be modeled or submetered, but doing so for even moderately sized geographic areas can be prohibitively expensive. Utility-load research data can provide key insights but understanding how demand-side management technologies and strategies will impact energy use is difficult. While matching building energy demand with available energy supplies is now more critical than ever, enabling practitioners to take decisive action remains challenging.

Through support from DOE, researchers at NREL developed ComStock, a sister tool to ResStock™. ComStock relies heavily on several extraordinary efforts spearheaded by private industry, DOE, and academia. Involved stakeholders have enabled ComStock to incorporate and operationalize the following data and modeling capabilities:

  • National commercial real estate databases
  • Detailed subhourly building simulations
  • High-efficiency sampling algorithms
  • National and regional energy use surveys
  • Advanced metering infrastructure data
  • High-performance and cloud computing.

These capabilities represent the work of thousands of researchers and will enable high-fidelity information delivery across stakeholder groups.

ComStock's most notable capability is being able to tailor the results to the question at hand. The results of the model are available at multiple levels:

  • Spatial: U.S., state, and county geographic resolutions
  • Temporal: Annual aggregations to 15-minute simulation intervals
  • Sectoral: 16 (and counting) building types.

ComStock provides access to results through a web visualization tool. Additionally, the raw results data sets (estimated at ~10 TB) will be available for download. ComStock is undergoing extensive validation and calibration to both timeseries whole-building and end-use data through the End-Use Load Profiles project and is expected to be fully released in October 2021. ComStock leverages and is deeply indebted to DOE's open-source building energy modeling ecosystem of OpenStudio® and EnergyPlus®.

Featured Projects

Electrification Futures Study

As part of NREL's Electrification Futures Study, the ComStock team developed a high-resolution data set describing the baseline commercial building electrical energy use. The modeling methods and results are described in the report. Although ComStock was in a very early stage of development at the time, this effort demonstrated the value of high-resolution, bottom-up load modeling capabilities across large geographic areas at an hourly basis.

Los Angeles 100% Renewable Energy Study

NREL developed a city-scale version of the ComStock model for the Los Angeles 100% Renewable Energy Study. In this study, NREL conducted a series of integrated modeling activities for the Los Angeles Department of Water and Power to understand the options and tradeoffs among different approaches to realizing the Los Angeles City Council's goal of meeting 100% of electricity demand with renewable resources. These integrated modeling activities involve using the modeling results from ComStock as inputs to distributed PV adoption, distribution feeder, and bulk power capacity expansion and production-cost models.


Contact Ry Horsey and Andrew Parker at to learn more about ComStock.