100 founding spots open · €99 lifetime

Diaz Editor vs OpenSolar
"Free" + per-proposal fees — or €99 once.

Honest comparison. OpenSolar's design tool is free but charges fees per accepted proposal. Diaz Editor wins on offline work + battery design + predictable costs. Bonus: Diaz Editor also handles electrical, HVAC, plumbing, and structural work — OpenSolar is solar-only.

Get founding spot — €99 → Read comparison ↓
Last updated: 9 May 2026 · By Juan Diaz, founder Diaz Atlas · 6 min read

TL;DR

OpenSolar is strong for sales-driven installers who want online proposals + e-signature + CRM. Diaz Editor is strong for design-driven installers who want speed, offline work, and battery design. Different philosophies — choose based on where your bottleneck is (sales or execution).

When OpenSolar is the right choice

For a sales-led residential install business, OpenSolar's workflow is well-built.

When Diaz Editor fits better

Side-by-side: features that matter

FeatureDiaz EditorOpenSolar
3D roof design
Works offline— (cloud-only)
Battery system design✓ (full)— (basic)
Branded proposals + e-signature— (export to your tool)
Built-in CRM
Per-deal costs€0— (proposal fee)
PDF permit pack export
Local language UI (NL/ES)✓ (limited)
Lifetime license available

Source: OpenSolar public pricing page + Diaz Editor v0.3 changelog. Updated May 2026.

Real costs: 'free' vs €99 lifetime

OpenSolar

Free*
* + fee per accepted proposal + paid add-ons
At 50 deals/yr × €15 fee = €3,750 over 5 years

Diaz Editor — Founding Beta

€99
one-time · all features · no variable costs
5-year total: €99

OpenSolar's exact fee per proposal depends on region and plan. The €15 estimate is conservative — for some markets it runs to €30+. Check their pricing page for your situation.

Migrating from OpenSolar to Diaz Editor — 3 steps

  1. Export your OpenSolar projects as PDF + CSV (BOM). Account → Export → All projects.
  2. Re-create in Diaz Editor — typical residential project 5-15 minutes thanks to faster roof tools.
  3. Combine with your own proposal template (Google Docs, Notion, or your CRM) — Diaz Editor's 3D renders are pitch-ready.

Honest verdict

For design-driven installers (solo + SMB)

Diaz Editor wins on speed + battery + offline + predictable cost. No surprises at month-end.

For sales-led installers with team

OpenSolar's all-in-one workflow may fit better. CRM + proposal + signature in one tool is valuable if sales is your bottleneck. Some installers use both: Diaz Editor for design, OpenSolar (or their own CRM) for sales flow.

Frequently asked questions

Is OpenSolar really free forever?

OpenSolar's design tool is free, but they charge per accepted proposal (transaction fee model) and offer paid add-ons (CRM, e-signature, payments). For high-volume installers, the proposal fees add up quickly. Diaz Editor has zero transaction fees.

Does Diaz Editor work offline like OpenSolar doesn't?

Yes. Diaz Editor is a desktop application — works fully offline. OpenSolar is cloud-only. If your internet is down or you're at a remote site, Diaz Editor keeps working.

Can I migrate from OpenSolar to Diaz Editor?

Export your OpenSolar projects as PDF + CSV. Re-create in Diaz Editor in 5-15 minutes per residential project. The roof traces are typically the longest part — Diaz Editor's roof tools speed this up.

What about OpenSolar's customer proposals?

OpenSolar's branded proposal generator is one of its strengths. Diaz Editor's PDF export is more design-focused (technical permit pack). For sales-pitch documents, you'd combine Diaz Editor's 3D output with your own proposal template.

Is OpenSolar better for sales-led installers?

OpenSolar's strength is the sales workflow — branded proposals, e-signature, CRM. If sales is your primary bottleneck, OpenSolar may fit. If design speed and offline desktop work matter more, Diaz Editor is the better tool.

Try Diaz Editor — €99 lifetime

100 founding spots. No subscription. No transaction fees.

Claim founding spot — €99

Other comparisons

What you get for €99

One-time. Lifetime. 3 seats. No subscription.

Built for self-employed tradespeople + small teams (1-10 people). Not for architects or utility-scale engineering — AutoCAD and Aurora are better at those.

Regular price (after founding):

€1.000 €99 today

Become a founding member — €99 →

100 spots total. Stripe checkout. Instant download after payment.

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