Project website:
Lead Performer: National Renewable Energy Laboratory (NREL) – Golden, CO
-- Lawrence Berkeley National Laboratory (LBNL) – Berkeley, CA
-- Skidmore, Owings, and Merrill – Chicago, IL
-- Ladybug Tools – Fairfax, VA
-- University of Colorado-Boulder – Boulder, CO
-- Comillas University – Madrid, Spain
-- City of Westminster, CO
-- Engie Lab, Saint-Denis, France
DOE Total Funding: $6,000,000
FY19 DOE Funding: $2,000,000
Cost Share: Anticipated from several project partners.
Project Term: October 1, 2018 – September 30, 2021
Funding Type: Lab RFP 2018
Related Projects: EnergyPlus, OpenStudio, Spawn

Project Objective

District- and campus-level projects present unique opportunities for energy optimization and grid responsiveness. The mixture of thermal and electrical use profiles combined with geographic proximity present the opportunity to leverage district thermal systems, co-generation, shared renewables and storage, and microgrids to improve efficiency, reduce demand, and provide measures of resiliency.

With few exceptions, current energy modeling (BEM) tools do not support district- and campus-level analysis. BTO’s own BEM platform, the EnergyPlus engine and OpenStudio software development kit, focus on individual building energy analysis—while OpenStudio supports large scale analysis, each simulation is independent of the others. As a result, designers are left to combine traditional one-building-at-a-time simulations with one another and other analyses in ad hoc ways, typically using pre- or post-processing that captures gross system properties, but lacks consideration of the geographic proximity and connections between buildings, distributed energy systems, thermal systems, and the grid. The lack of foundational integrated analytical capabilities is a challenge for both technology R&D and real-world projects.

URBANopt (Urban Renewable Building And Neighborhood optimization) is an EnergyPlus and OpenStudio-based simulation platform aimed at district- and campus-scale thermal and electrical analysis. Originating as NREL Laboratory-Directed Research and Development (LDRD) project, URBANopt is being elevated to a more formal position within BTO’s ecosystem of tools.  This three year project will focus on enhancing URBANopt capabilities for modeling shared thermal systems, supporting integration with grid and distributed energy resources (DER) analysis tools, structuring the project as an open-source software development kit that is suitable for integration into commercial products, and piloting the underlying analytics in real world projects.

The URBANopt project initially focuses on enabling three types of use cases:

  • Design of low energy campuses and districts.
  • Design and optimization of grid-interactive efficient buildings (GEBs) at a district-scale in conjunction with distributed energy resources (DERs) and electric distribution systems.
  • Detailed design of next-generation district thermal systems.

To enable these analytical use cases, development efforts will focus on:

  • Software Development Kit: In August 2019, BTO announced that it will transition the graphical OpenStudio Application to to-be-named third parties and focus its efforts on the OpenStudio software development kit (SDK) which supports the development of applications and services. URBANopt will also be released as an SDK rather than an end-user tool. The team will develop this SDK while private sector software developers integrate it into their existing end-user platform.
  • Electrical System Simulation: DER, microgrid, and electrical distribution system design are important URBANopt use cases. In this part of the project, the team will leverage automated data exchange and APIs (application programming interfaces) to integrate Open Distribution System Simulator (OpenDSS) and Reference Network Model (RNM) simulation capabilities into URBANopt.
  • Physically Realistic District Thermal System Co-Simulation: As with most other tools, URBANopt currently does not directly “co-simulate” buildings and shared thermal systems. Instead, it simulates the buildings individually, collects thermal load profiles and then post-processes those to a separate district-system simulation tool. While the URBANopt SDK will initially be based on the current approach, the team will create a parallel path for a more physically realistic co-simulation approach. This path will use the Modelica equation-based simulation language to model shared thermal system with advanced features such as ambient temperature loops, thermal storage, waste heat recovery, and bi-directional flow. Importantly, it will also support co-simulation with building models at multiple levels of detail including detailed Spawn models, reduced order models (ROM) and data-driven black-box models.

Each of these use cases is based on real world questions and foundational analytical needs and gaps that NREL has encountered in district-scale projects. The efforts related to each use case will be coordinated with real world testbed projects leveraging several private-sector partners. These projects inform development and provide real-world platforms for testing new or enhanced modeling capabilities. 

URBANopt is a simulation platform and SDK for low-energy campuses and districts comprising buildings, shared thermal resources, and DERs.
The URBANopt project will enhance the existing platform with: i) APIs suitable into third-party workflows, ii) electrical system simulation capabilities, and iii) shared-thermal system co-simulation capabilities.

Project Impact

Planners, engineers, and electric utilities are currently challenged to: i) understand the impacts and interactions districts have with the local and bulk electricity distribution systems, and ii) to identify opportunities for additional efficiencies and cost savings through the concurrent design, upgrade, and/or optimization of buildings, DERs, and the electricity distribution infrastructure.

The URBANopt project is focused on addressing these critical gaps by providing advanced analytical capabilities that will accelerate R&D in district and campus level energy-efficiency and grid-interaction technologies and strategies while supporting real-world projects, e.g., Zero Energy Districts.


DOE Technology Manager: Sarah Zaleski and Amir Roth
Lead Performer: Ben Polly, National Renewable Energy Laboratory (NREL)

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