Case study / CzystePro

CzystePro — Energy audits and proposals

A platform with an energy calculator, a ZUM equipment database and PDF proposal generation.

Problem

Calculations, equipment selection and document preparation involve several tools.

What I built

A platform with an energy calculator, a ZUM equipment database and PDF proposal generation.

  • ISO 13790-based calculator and Glaser analysis
  • Heating system comparison and ZUM database
  • PDF proposals, AI assistant and auditor collaboration

User feedback

Instead of calculating in Excel and searching devices on the ZUM website, I complete an entire pre-audit in 5 minutes on my phone. The client gets a PDF offer right away — before competitors can even call back. CzystePro changed the way I work.

Tomasz K.
Renewable Energy Salesperson, Clean Air program · Greater Poland

Tech Stack

Next.js 15 React TypeScript Supabase Google Gemini Stripe PWA ISO 13790 Vercel

Why this stack?

  • Next.js 15 + Server Components — fast rendering, content SEO, subdomain routing (LP + SaaS)
  • Supabase (Postgres + RLS) — per-organization data isolation, real-time audit sync, Auth with roles (seller/auditor/admin)
  • Google Gemini AI — chatbot trained on regulations, WT 2021 building codes, and subsidy conditions. Per-user credit system
  • PWA + Service Worker — cache-first for static assets, network-first for pages. Salespeople work offline in the field
  • Stripe — SaaS subscriptions with checkout, role-based plans

Have a similar project?

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