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Computational framework for behind-the-meter DER techno-economic modeling and optimization: REopt Lite


The energy system is undergoing a major transformation with the global emphasis on decarbonization. Distributed generation is projected to play a significant role in the new energy system, and energy models are informing how distributed generation can be integrated reliably and economically. In this work, we present an end-to-end computational framework for distributed energy resource (DER) modeling, REopt Lite™, which captures the interface of technology, economics, and policy in the energy modeling process. We describe the problem space, the building blocks of the model, the scaling capabilities of the design, the optimization formulation, and the extensibility of the model. We present a framework for accelerating the techno-economic analysis of behind-the-meter distributed energy resources to enable rapid planning and decision-making, thereby enabling greater renewable energy deployment. This computation framework is open-sourced to facilitate transparency, flexibility, and wider collaboration opportunities within the worldwide energy modeling community.

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  1. Note that the described limitations are combined from all the tools, they may or may not be present in every single referenced tool.

  2. SAM being a notable exception, which has been open-sourced.

  3. Open-sourced under BSD-3 License, which is permissive with minimal restriction on use and distribution.

  4. See

  5. See

  6. Diesel generator is restricted to resilience applications only in the webtool; grid-connected use of diesel generators is allowed in the API.

  7. Theoretically unlimited, but in the code implementation a big number (10e + 7) is used.


  9. Information on state net metering limits is available at







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This work was authored by the National Renewable Energy Laboratory, operated by Alliance for Sustainable Energy, LLC, for the U.S. Department of Energy (DOE) under Contract No. DE-AC36-08GO28308. Funding was provided by the U.S. Department of Energy Office of Energy Efficiency and Renewable Energy Federal Energy Management Program and the Advanced Manufacturing Office. The authors would like to thank Andy Walker, Linda Parkhill, Kathleen Krah, Andrew Jeffery, Nick Muerdter, Xiangkun Li, Rob Eger, and Nicholas DiOrio for help with building and maintaining the REopt Lite API; and Adam Warren for reviewing the manuscript. The authors would also like to thank Rachel Shepherd (Office of Energy Efficiency and Renewable Energy, DOE) and Bob Gemmer (Advanced Manufacturing Office, DOE) for funding this work. The views expressed in the article do not necessarily represent the views of the DOE or the U.S. Government. The U.S. Government retains and the publisher, by accepting the article for publication, acknowledges that the U.S. Government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this work or allow others to do so, for U.S. Government purposes.

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Mishra, S., Pohl, J., Laws, N. et al. Computational framework for behind-the-meter DER techno-economic modeling and optimization: REopt Lite. Energy Syst 13, 509–537 (2022).

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  • Renewable energy optimization
  • Mixed-integer-linear-programming
  • JuMP model
  • Behind-the-meter DERs
  • Microgrid design
  • Open-source energy software
  • Energy modeling