May 2025: Key features delivered, major QA improvements, and stronger maintainability for NREL/REopt.jl. Core work focused on HVAC sizing accuracy, GHP/GHX sizing predictability, and expanded validation of payback metrics, driving clearer business outcomes and robust production readiness.

April 2025 performance summary for NREL/REopt.jl, focusing on delivering core features, stabilizing calculations, and improving testability. The work emphasizes business value through more accurate reporting, expanded scenario capabilities for planning, and cost-aware sizing while maintaining high code quality and robust runtime diagnostics.

March 2025 monthly summary for NREL/REopt.jl: Key observability improvements delivered to heating load calculations; CSV logging of heating_load_mmbtu across multiple stages; commit 12246fe2d9b1b4d4c61ce248e7516da94f87ed8c updated scenario.jl to support instrumentation. No major bugs fixed this month. Overall impact: faster debugging and improved performance analysis of the GHP load serving logic, enabling more reliable optimization results and quicker issue diagnosis. Technologies/skills demonstrated: Julia development, CSV-based observability instrumentation, scenario integration, Git-based collaboration.

February 2025 monthly summary for NREL/REopt.jl: Key feature delivered a robust implementation for Ground Source Heat Pump (GHP) borehole sizing, enforcing user-defined maximum boreholes, and ensuring the optimization outputs respect the cap. This included corrections to naming and calculation paths to maintain correct sizing across the GHP and Scenario modules. Major code updates also touched scenario.jl to reflect the new sizing logic. Major bugs fixed include: fixes to naming inconsistencies and calculation paths that could mis-size boreholes, ensuring the borehole output aligns with the user-specified maximum, and general code hygiene to prevent regressions in borehole sizing logic. Overall impact and accomplishments: Enhanced modeling fidelity and reliability for GHP designs, enabling designers to confidently cap borehole counts without sacrificing optimization quality. Reduces risk of over- or under-sizing, improves user trust, and accelerates project planning by delivering consistent sizing results across modules. Technologies/skills demonstrated: Julia language improvements, module interaction between GHP and Scenario components, loop constructs to enforce caps, parameter normalization, scenario synchronization, and code maintenance with naming corrections and cleanup.

January 2025 performance summary: Delivered two core feature enhancements across REopt.jl and REopt_API, with targeted correctness improvements and stronger data validation that enhance modeling accuracy and API flexibility. GHP modeling enhancements in REopt.jl add load_served_by_ghp with two modes, refactor non-peak load handling, and ensure correct sizing when users specify GHP size. BESS duration controls in REopt_API introduce min/max duration hours in ElectricStorageInputs, with defaults and validation to improve data integrity. These changes reduce mis-sizing risk and enable more reliable, scalable energy analyses.

December 2024: Delivered enhanced Geothermal Heat Pump (GHP) sizing with user-defined max_ton and robust handling of undersized loads in NREL/REopt.jl. Implemented changes across scenario logic, GHP/GHX modeling, and load calculations; included refactors for maintainability and updated changelog. This work provides customers with explicit capacity limits, ensures models re-run with updated inputs, and improves accuracy of sizing under undersized loads, reducing risk in feasibility analyses.