OpenSolar is the closest thing the solar industry has to a global default: free, used in over 160 countries, and backed by tens of thousands of businesses. This review is for Australian installers working out whether the world's most popular free platform is the right fit locally, where it shines, and where being global-first leaves gaps.
What is OpenSolar?
OpenSolar is a free, cloud-based solar design, CRM and proposal platform used by well over 25,000 businesses across more than 160 countries. Rather than charging installers, it's funded by hardware manufacturers and finance providers who integrate with the platform. That model has made it one of the most widely adopted tools in solar, and shapes both its strengths and its blind spots.
What is OpenSolar best at?
OpenSolar is best at delivering capable design at zero software cost, at scale. The core platform is genuinely free, with no per-seat fees or design caps, and includes fast 3D design, solid shading and production estimates, CRM, e-signatures and payments in one place since version 3.0. Backed by a huge global community and deep hardware-partner integrations, it's a remarkably complete package for the price, which is nothing.
Where does OpenSolar fall short for Australian installers?
OpenSolar falls short exactly where being global-first meets Australian compliance. The specific gaps:
- No native compliant SLDs. It doesn't generate AS/NZS 5033 single-line diagrams the way a local tool does, so many installers still use separate CAD software.
- Not Australia-specific. STCs, the Federal Battery Rebate and AS/NZS documentation aren't the central focus they are in a purpose-built Australian platform.
- Partner-funded data flow. Because hardware and finance partners fund it, project data flows to them by design and the roadmap serves that ecosystem.
- Paid API. External API access became a paid feature from April 2026, which matters for integration-heavy businesses.
Who is OpenSolar best for?
OpenSolar is best for installers doing relatively straightforward residential work who want a capable, no-cost platform and are comfortable with the partner-funded model. Plenty of Australian installers run their entire sales process on it happily. It's the compliance-heavy and battery-focused work, where AS/NZS 5033 SLDs and precise rebate handling matter, that exposes its global-first limits.
How does OpenSolar compare to Solar Proof?
The contrast is free-and-global versus local-and-compliant. OpenSolar is free and worldwide; Solar Proof is paid but Australian-built, with STCs, the Federal Battery Rebate and AS/NZS 5033 SLDs handled natively, founded in 2017 and used by over 1,000 solar professionals. If cost is your priority, OpenSolar wins; if local compliance is, Solar Proof does. See the full Solar Proof vs OpenSolar comparison.
The bottom line
OpenSolar is an excellent, genuinely free, globally-proven platform, and a strong choice for straightforward Australian residential work. Its limits are the SLD and AU-compliance gaps that come with being global-first. If those gaps cost you time, weigh a purpose-built Australian alternative; if they don't, free is hard to argue with.
