OpenSolar Review 2026: Genuinely Free, With Real Trade-offs

Most software reviews start from the assumption that you are choosing between things you pay for. OpenSolar breaks that frame, because it costs an installer nothing and always has. That makes it the hardest product in this category to review honestly, since the easy criticisms fall apart the moment you remember the invoice is zero. So this review takes the product at face value first. What OpenSolar does, who it does it for, where the engineering genuinely thins out, and the specific point at which a growing installation business stops being served by it. We have used OpenSolar alongside Aurora, PVsyst, and SurgePV on live jobs, and the trade-offs below are the ones that showed up in the work.

Short version. OpenSolar is a free cloud solar design and proposal platform, which the vendor describes as funded by hardware and finance partners rather than by installer subscriptions. It is a legitimately good residential tool: fast layouts, clean customer-facing documents, strong presence in Australia, the UK, and Ireland. Its limits show on bankable yield reporting, hourly battery modelling, and markets outside its core territories.

What OpenSolar Is, and How the Free Model Actually Works

OpenSolar is a browser-based platform for designing residential solar systems and turning them into customer proposals. You enter an address, it pulls imagery, you trace the roof and place modules, it estimates production, applies an incentive and tariff assumption, and generates a branded document you can send or present.

The part that separates it from every competitor is the price. There is no per-seat fee, no design cap, and no expiring trial on the core workflow. An installer with one van can run the same product as an installer with thirty.

That money has to come from somewhere, and OpenSolar says openly where. Its publicly described model puts revenue on the other side of the transaction: hardware manufacturers and finance providers who pay for integration and transaction flow within the platform. This is a normal marketplace business model and OpenSolar has never disguised it.

It is worth understanding for two practical reasons, and neither is an accusation of bad faith.

First, it is a reasonable lens on investment priorities. A product funded by hardware and finance partners has an obvious commercial reason to be excellent at the customer-facing sale and at getting a deal financed. A lender-grade yield engine or a deep multi-country compliance library serves a different audience, and in our view that shows in where the product is strongest.

Second, integrated platforms make specifying integrated options easy, which is the point of them. You remain free to specify whatever you want, and plenty of OpenSolar users do exactly that. Defaults carry weight in any tool, so review them on their merits rather than accepting them, exactly as you would in any platform with supplier integrations.

What OpenSolar Genuinely Does Well

It costs nothing, and that is a real advantage. For an installer doing 3 to 8 residential jobs a month, a $1,500 annual software line is a meaningful share of overhead. Removing it entirely is not a gimmick. It is the single biggest reason OpenSolar built the installer base it has, and any review that treats free as suspicious is arguing in bad faith.

Fast residential layout. For a standard pitched roof with ordinary obstructions, you can get from address to a placed array quickly. The tooling is designed around the common case rather than the hard case, which is the correct decision for the work most residential installers actually do.

Presentable customer documents. The proposal output looks professional to a homeowner. Compare it to what a small installer produces without a tool, usually a spreadsheet extract and a photograph. That gap closes deals, and OpenSolar hands it to you for free.

Real footprint in Australia, the UK, and Ireland. These are the markets OpenSolar highlights most in its own materials, and in our experience the defaults match local practice best there. Familiarity carries commercial value when a customer has already seen the same proposal format on three other quotes.

The lowest barrier to entry in the category. A new installer can produce credible quotes on day one at zero cost and zero procurement approval. Nothing else in this market comes close on that measure.

Where OpenSolar Falls Short

Yield reporting is thinner than PVsyst. OpenSolar produces a production estimate that is fine for selling a domestic system. It is not positioned as bankable yield reporting. Bankability is a specific thing: an hourly simulation with a documented loss chain, transposition and temperature models a reviewer can interrogate, and probability outputs like P50 and P90. Lenders and independent engineers ask for that because they need to underwrite a number, not admire it. If a financier asks you for a yield report, check the format they expect before assuming a sales-grade estimate will satisfy it.

Code depth is lighter. In our own use, electrical code handling is present but lighter than in tools that market themselves on it. String sizing at design temperature, rapid shutdown provisions, and validation against a named standard are areas where paid engineering tools do more of the automated checking for you. On a simple residential job this rarely bites. On anything unusual, expect to do more of the compliance checking yourself before a design goes to a plan reviewer, in this tool as in any other where the checks are not automated.

Hourly self-consumption and battery dispatch modelling is weaker. This one is growing in importance faster than anything else on the list. Battery economics live in the hourly detail. Whether a battery pays back depends on when the household actually consumes, when the array produces, what the export rate is against the import rate, and how the dispatch rules behave across a year. An 8,760-hour simulation captures that. Coarser methods tend to flatter self-consumption, which in export-poor markets can mean a payback figure that is optimistic in the customer’s favour and awkward eighteen months later. Test your own numbers against an hourly model before you rely on them either way.

Incentive and tariff libraries are limited outside its core markets. Outside Australia, the UK, and Ireland, the depth drops. Incentive structures, subsidy schemes, and time-of-use tariff shapes vary enormously by country and by utility, and maintaining that library is expensive work. If you sell in a market OpenSolar has not invested in, you will rebuild the financial half of the proposal in a spreadsheet, which is exactly the work the software was supposed to remove.

Integrated partners are part of the model. Stated as description rather than complaint: OpenSolar publicly describes a business model funded by hardware and finance partners, and the platform surfaces integrated equipment and financing paths accordingly. Nothing stops you specifying otherwise. If you specify equipment strictly on spec, review the preloaded selections each time rather than accepting them, which is sound practice in any platform with supplier integrations.

What Free Actually Costs You

Strengths Against Limitations

The Ceiling: When a Growing Installer Outgrows It

The transition point is the useful part of this review, because everything else is predictable. Here is the checklist we use.

Two or more being true is usually enough. One rarely is.

Nothing in that example is a criticism of OpenSolar. The installer at 14 simple residential jobs a month was correctly served. The business changed shape underneath the tool.

Who Should Use OpenSolar

• New installers. Zero cost, zero procurement, credible documents from day one. There is no better starting point.
• Low-volume residential teams. If you do straightforward roofs in one market and nobody is asking you for a bankable report, paying for software would be paying for capability you will not use.
• Anyone who needs a good customer document with no budget. The proposal output alone justifies the install.
• Installers in Australia, the UK, and Ireland doing domestic work. This is the product’s home ground and it shows.

Who Should Not Use OpenSolar

• Teams needing bankable yield reporting. The output is not positioned for what a lender means by that word, so check the required format before you commit.
• Anyone doing serious battery and tariff modelling. Hourly dispatch resolution is the difference between an honest payback figure and an optimistic one.
• Multi-market operators. Compliance and incentive libraries outside the core markets will cost you more in manual work than a licence costs.
• Commercial and ground-mount heavy pipelines. Layout flexibility and inter-row shading depth are not where this product invested.
• Teams that want hardware neutrality guaranteed by their tooling. Not because the platform prevents specifying anything you like, but because in a partner-funded model the discipline of checking each selection sits with you.

Alternatives Worth Comparing

SurgePV, the usual next step. SurgePV runs $1,299 to $1,899 per user per year depending on team size, with design, 8,760-hour module-level shading, financial modelling, and white-label proposals in a single licence. It is the natural upgrade specifically because it addresses the four things OpenSolar is thin on: bankable yield outputs, hourly battery and self-consumption modelling, multi-market code and tariff coverage, and an equipment database with no supplier-funded integrations behind it. The trade-off is that you now have a software bill, and a smaller community than OpenSolar has built. Our OpenSolar alternative comparison covers the migration path and the other options in detail, and the true cost breakdown of OpenSolar works through the add-on arithmetic.

Aurora, for US residential depth. If your work is high-volume US residential, Aurora’s remote roof assessment and sales presentation are deeper than anything free. Aurora is quote-based and reported figures vary, commonly cited around $159 to $259 per user per month before separately licensed modules, so confirm with the vendor. In our view it earns that at volume in a single US market and does not earn it elsewhere. The Aurora Solar review goes through the pricing structure and the fit test.

PVsyst, for bankable work. When a financing agreement names PVsyst, the question is not which tool is better but which output the contract accepts. Most teams run PVsyst for the report and something faster upstream. The PVsyst alternative comparison explains when substitution is possible.

For the wider view, the solar design software pricing comparison puts annual costs side by side, and the commercial solar design software guide covers what changes when C&I enters the pipeline. On bankability specifically, the PV yield simulation guide explains what lenders check.

Verdict

OpenSolar is a good product and the free model is honest. It has done more to lower the barrier for small installers than anything else in this category, and it deserves credit for that rather than suspicion. If you are doing straightforward residential work in one market, particularly in Australia, the UK, or Ireland, there is no defensible reason to pay for something else. Paying would be buying depth you would not use.

The real question is not value for money, because there is no money. It is timing. OpenSolar has a ceiling, and unlike a subscription renewal, nothing prompts you when you reach it. The signals are indirect: a bank asking for a report you cannot produce, batteries in most quotes, a designer quietly living in a spreadsheet, a second market with tariffs the tool does not know. By the time those are obvious, you have usually been paying for them in labour for a while.

So use OpenSolar until the mix changes, and watch for the change deliberately. When two or more items on the checklist above go true, price the workaround labour against a paid licence honestly. For most teams at that point the arithmetic favours moving, and SurgePV at $1,299 to $1,899 per user per year is the closest match on workflow. Until then, the free tool is the right answer and you should not let anyone talk you out of it.

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About This Comparison

Pricing, features and product positioning described here were checked in August 2026 using publicly available vendor information. Vendors change pricing, packaging and capabilities without notice, and several do not publish prices at all. Treat every figure as a starting point for your own enquiry rather than a quotation, and confirm current terms directly with each vendor before making a purchasing decision.

All product names, logos and trademarks are the property of their respective owners. Reference to them here is for identification and comparison only and does not imply any affiliation with, sponsorship by, or endorsement from those companies. SurgePV is a Qbits Energy product, so treat this as a vendor comparison written by an interested party and weigh it alongside independent sources and your own trial of the tools.

Where we could not verify a claim from a primary source we have said so in the text rather than repeating it. If you believe anything here is inaccurate or out of date, contact us and we will review and correct it.