Least-Cost Optimal Distribution Grid Expansion (LODGE) Model

Uncertainty in interconnection costs and timelines has been identified by the National Community Solar Partnership (NCSP) as one of the most persistent barriers to community solar deployment. Interconnection delays impact community solar due to the in-front-of-the-meter structure found in nearly every project.

NCSP has partnered with Lawrence Berkeley National Laboratory (LBNL) to develop the Least-Cost Optimal Distribution Grid Expansion (LODGE) model. This model identifies the most cost-effective ways community solar and storage can be sited on the grid, with a focus on minimizing interconnection costs and maximizing deployment. The LODGE model uses data provided by local utilities to identify strategic siting points along the grid that are cost-optimal for interconnecting community solar and storage. The model has the potential to lower costs for developers and utilities and promote increased deployment of distributed energy generation and storage.

Approach

To develop the LODGE model, LBNL analyzed more than 2,000 feeders, or small-supply power lines, that were modeled to emulate distribution grids in three utility territories: the San Francisco Bay Area in California; Austin, Texas; and Greensboro, North Carolina. The LODGE model also leans on the findings from LBNL’s REPAIR model, which focuses on upgrades to distribution circuits and feeders. These prior analyses helped shape the LODGE tool, contributing to the effort to better map the distribution grid and cost-optimal upgrades.

LBNL aims to pilot the LODGE model in partnership with electric public utility commissions (PUCs) and electric utilities, beginning with the Oregon Public Utility Commission. In order to operate successfully, the model needs utility data to find and present options that reduce upgrade costs and identify the best points of interconnection. The pilot will enable testing of the LODGE model and utilize the findings to help integrate community solar and other distributed energy resources more efficiently into the grid. Piloting of the LODGE model is expected to be completed in summer 2024 with a formal technical assistance program to follow.

Become a LODGE Model Pilot Partner

LBNL and DOE seek additional utility and electric public utility commission participation in the pilot. Participating electric PUCs and utilities will have the chance to be a part of DOE’s larger effort to address strategic solar energy siting and interconnection queues.

Become a LODGE model pilot partner and watch a recording of the interconnection and LODGE model webinar.

Pilot Participation Requirements
  • Participating teams should identify one lead representative from the utility and one lead representative from the electric PUC.
  • Beyond data sharing, DOE and LNBL expect lead representatives to participate in the following activities:
    • Scoping meeting (1 hour) 
    • Monthly check-ins (30 minutes) 
    • Data presentation (1 hour) 
  • DOE and LNBL expect participants to be responsive to email or phone requests for additional information within 24-48 hours to ensure a timely completion of data analysis.
  • Participants may be asked to complete an evaluation of their experience participating in the pilot process and the value of the results.
  • Participants may also be asked to take part in optional events related to the LODGE tool, including webinars or presentations on the impacts of the tool’s findings.
Minimum Data Sharing Requirements
  • Distribution feeder models in CYME or OpenDSS formats are preferable. Other formats may be accepted.
  • Advanced Metering Infrastructure (AMI) data (at least one year’s worth).
  • Infrastructure capital costs and lifetime: substation, transformers, line reconductoring, voltage regulator, and storage.
  • Potential suggestions for community solar or distributed energy resource locations.

Additional Information