project-solavin# Solavin — Photovoltaic Characterization Suite

A lab-grade web application for analysing photovoltaic current–voltage (I-V) sweeps. Upload measured data, and Solavin extracts the standard figures of merit — short-circuit current (I_sc), open-circuit voltage (V_oc), maximum power (P_max), fill factor (FF), series and shunt resistance (R_s, R_sh) and power-conversion efficiency (η) — with interactive I-V / P-V / radar visualisations and one-click CSV/Excel export.

Built with React 18 + Vite + Recharts. The scientific core is plain, dependency-free JavaScript covered by an automated test suite, so results are reproducible and verifiable.

Developed by John Myron Uy, under the guidance of Prof. Raymund Sarmiento — Research Laboratory, Solar Cell Characterization.

---

Highlights

• Parameter extraction — I_sc, V_oc, P_max, V_mp, I_mp, FF, R_s, R_sh, η.
• Multi-channel — load many sweep conditions per dataset and compare them.
• Visualisations — I-V, P-V (with MPP markers), normalised radar profile, and ranked P_max comparison; brush-to-zoom and a voltage cursor lookup.
• Data ingest — drag-and-drop .xlsx / .xls / .csv; multi-sheet picker.
• Export — CSV and XLSX of the full metrics table, including η when area and irradiance are supplied.
• Lab Assistant — an offline, deterministic analyser that answers from the extracted metrics (summaries, rankings, fill-factor interpretation, suggested experiments). No external API, no keys.
• Local operator profiles — name a session to keep a persistent dataset library in your browser, or work in demo mode. No passwords, no backend.
• Two build targets — a normal web app for hosting, and a single self-contained .html you can email or run offline from file://.

Accuracy & conventions

Photovoltaic figures of merit are computed in src/lib/ivAnalysis.js on the signed current (generator convention: current is positive in the power-producing quadrant and negative beyond V_oc).

Quantity	Definition used
Isc	Current at V = 0 (exact sample, else interpolated; extrapolated if the sweep starts above 0 V).
Voc	Voltage at the first I = 0 crossing (linear interpolation). Flagged if it lies beyond the sweep range.
Pmax, Vmp, Imp	Maximum of V·I, restricted to the power quadrant (V ≥ 0, I ≥ 0).
FF	Pmax / (Isc · Voc) — always < 1 for physical data.
Rs	|dV/dI| near Voc (slope estimate).
Rsh	|dV/dI| near Isc (slope estimate).
η	Pmax / (G · A), with cell area in cm² and irradiance G in W/m².

R_s and R_sh are first-order slope estimates from a single light sweep; a dark I-V curve or a full single-diode fit gives more rigorous values.

The test suite (src/lib/ivAnalysis.test.js) asserts these invariants on every build — including that the fill factor is always between 0 and 100 % — so the extraction cannot silently regress.

Data format

Column A is voltage (volts); each subsequent column is one current sweep (amperes, signed). Row 1 holds headers, which become channel labels.

Voltage(V), Focused Laser, -2mm, +6mm Focus
0,          1.539e-6,      1.46e-6, 1.583e-6
0.05,       1.528e-6,      1.456e-6, 1.565e-6
...
2.5,        -3.875e-6,     -3.052e-6, -2.923e-6

A ready-to-upload example lives in examples/sample_iv_data.csv (the same dataset the app loads by default).

Getting started

npm install
npm run dev          # start the dev server (http://localhost:5173)
npm test             # run the physics unit tests
npm run build        # production build → dist/
npm run build:standalone   # single self-contained file → dist-standalone/index.html
npm run build:all    # both builds

Standalone file

npm run build:standalone produces dist-standalone/index.html — a single file with all JavaScript and CSS inlined. Open it directly (file://…) with no server; it works offline (web fonts fall back to system fonts when there's no network).

Deployment (Netlify)

This repo includes netlify.toml. To go live:

1. Push the repository to GitHub.
2. In the Netlify dashboard, Add new site → Import an existing project and pick this repo.
3. Netlify reads netlify.toml automatically (build npm run build, publish dist). No manual configuration needed.

Every push then redeploys. The continuous-integration workflow (.github/workflows/ci.yml) runs the unit tests and both builds, and uploads the standalone HTML as a downloadable artifact.

Project structure

src/
  lib/
    ivAnalysis.js        # parameter extraction + parsing + export helpers (pure)
    ivAnalysis.test.js   # physics invariants & reference-value tests
    assistant.js         # deterministic, offline dataset analyser
  components/
    ProfileGate.jsx      # local operator gate (no passwords)
    Tour.jsx             # guided walkthrough overlay
    Assistant.jsx        # lab-assistant side panel
    shared.jsx           # chart tooltip, channel toggles, lookup, raw-data table
    AboutPage.jsx
  App.jsx                # main application
  theme.js  icons.jsx  persistence.js  styles.css  main.jsx
examples/sample_iv_data.csv
tests/e2e.smoke.mjs      # optional browser smoke test (skips if no Chromium)

Testing

• npm test — Vitest unit tests for the extraction math (run in CI).
• npm run test:e2e — optional Playwright smoke test that builds the standalone bundle, drives it in a real browser, and verifies the app mounts cleanly with physical fill factors. Playwright is not a default dependency; install it first with npm i -D playwright && npx playwright install chromium. The test skips automatically (exit 0) if Playwright or a browser is unavailable, so it never blocks CI.

License

MIT © 2026 John Myron Uy.