January 2026 (Month: 2026-01): Delivered targeted updates to NREL/REopt.jl to improve model fidelity and standards alignment. Implemented Boiler Emissions Factors in the Emissions Model to increase accuracy of emissions outputs, including a focused bug fix to ensure stable integration (commit: e9d0a1f6d0358832abed8fe3ac61ba000f78ec70). Updated federal financial input defaults to reflect the 2025 NIST Handbook and Annual Supplement, enhancing realism for federal sector analyses. Documented changes via CHANGELOG.md to support release readiness and traceability. Overall, these changes improve decision-relevant accuracy for policy and project-level analyses while maintaining rigorous documentation and compliance.

December 2025 monthly summary for NREL/REopt.jl: Delivered robustness improvements and code quality enhancements centered on logging and emissions-factor utilities. Key changes include robust handling of log file names through path-length checks and a refactor of emissions factor handling in utility functions to improve clarity and maintainability. These changes reduce production risk, improve debuggability, and prepare the codebase for future emissions-related features. Tech outcomes include improved log reliability, clearer utility interfaces, and alignment with long-term maintainability goals.

Month 2025-11 — NREL/REopt.jl focused on improving developer onboarding and usage clarity through targeted documentation enhancements. Clarified REopt.jl purpose and functionality, including integration with the REopt API and Web Tool, with explicit emphasis on heating and cooling technologies in energy optimization. No major bugs fixed this period. Impact: clearer guidance for users, reduced onboarding time, and smoother API/Web Tool integration, enabling faster adoption of REopt.jl in energy optimization workflows. Technologies/skills demonstrated: technical writing, Markdown documentation, version control, API documentation practices, and Julia ecosystem familiarity.

October 2025 monthly summary for NREL/REopt_API: Delivered a targeted dependency update to REopt.jl by locking Manifest.toml to a newer git-tree-sha1 and version, pulling in upstream improvements and bug fixes. This change was applied with a single commit (Update Manifest.toml). The update preserves API compatibility while improving build reproducibility and external repository quality.

September 2025 monthly summary focused on strengthening financial fidelity and storage modeling while modernizing dependencies and interfaces. Delivered MACRS depreciation and ITC refinements across CHP, GHP, Steam Turbine, PV, and storage; disabled accelerated MACRS for CHP/GHP; updated bonus fractions and option years; migrated input models and database fields. Implemented battery degradation enhancements with vector cycle fade coefficients, updated defaults, and new outputs for segmented cycle fade and total residual capacity. Updated REopt.jl dependency to a newer version (Manifest.toml aligned) and refreshed API dependencies. Strengthened test coverage (GHP tests, PV cost/premium corrections) and updated changelogs across CHP, Thermal Storage, PV, Wind, and GHP. Cross-repo coordination ensured consistent modeling and user experience.

August 2025 focused on strengthening financial modeling accuracy, API reliability, and development governance across the REopt portfolio. Key parameter refinements, test alignments, and dependency controls deliver measurable business value for investment decisions and platform stability.

June 2025 — NREL/REopt.jl monthly summary. Focused on delivering business-value features for electric storage economics, improving modeling flexibility, data presentation, and documentation. Major bugs fixed include enabling mutable financial modeling by removing the BAUFinancial constructor and clarifying financial outputs, plus rounding data visuals for stability. The work enhances decision support for storage investments and utility-scale analyses, and improves maintainability and readability of outputs.

May 2025 monthly summary focusing on expanding cost modeling capabilities, improving financial inputs/outputs, and increasing modeling flexibility across NREL/REopt.jl and NREL/REopt_API. Delivered groundwork for upfront cost tracking, more accurate lifecycle cost estimates, and robust input validations. Result: stronger business value through precise cost accounting for CHP, Microgrid upgrades, and incentives, plus better BAU planning and release readiness.

April 2025 delivered substantial business value by strengthening capital expenditure modeling, improving visibility into initial capex, and updating API documentation. Core work focused on refining CHP capex calculations and reporting in NREL/REopt.jl, along with API inputs and PV density documentation in NREL/REopt_API, supported by targeted code cleanup to remove legacy functions and improve maintainability. The changes enhance decision support for project finance, reduce ambiguity in financial results and constraints, and improve developer experience through clearer changelogs and documentation.

March 2025 performance summary for NREL REopt projects. Delivered core feature enhancements and robustness improvements across REopt.jl and REopt_API, enabling more accurate financial modeling and richer scenario analysis for customers planning renewable investments. Emphasis on data-driven incentive calculations, CAPEX feasibility checks, and clearer documentation to support decision making.

February 2025 monthly summary for NREL/REopt_API focusing on developer-facing release documentation for REopt.jl 3.12.0. Key work included delivering Release Notes and API Changes documentation, aligning version tracking with REopt.jl v0.51.0, and clarifying how to use new electric storage parameters, a supported API endpoint change, and leap year handling. This month included two commits updating CHANGELOG.md to reflect the release and API changes. No code changes were recorded this month; emphasis was on documentation, versioning, and process improvements to reduce onboarding time and support load.