Nobody leaves SAM because SAM is bad. NREL’s System Advisor Model is free, open, and rigorous, and for techno-economic work it has no equal at any price. Teams leave because their job changed. Once you are quoting roofs, drawing permit sets, and sending proposals every week, the analysis is the small half of the day. This guide ranks the tools that cover the other half.
Direct answer. The best SAM alternatives in 2026 are SurgePV for installers and EPCs who need design, shading, drawings, and proposals in one licence at $1,299 to $1,899 per user per year, PVsyst when a lender must accept your yield at about $500 per user per year for a standard licence, HelioScope for fast commercial layout, Aurora Solar for US residential sales, OpenSolar for free residential volume, and HOMER Pro for hybrid and microgrid architecture.
TL;DR
- SAM answers whether a technology and a financial structure are viable. It does not produce a roof layout, a shading scene, a drawing set, or a customer proposal.
- SurgePV ranks first for installers and EPCs because one licence carries the array from simulation through single-line diagram, DWG, and white-label proposal.
- PVsyst stays the answer when an independent engineer or lender reviews the yield number.
- HelioScope, Aurora, and OpenSolar each solve a narrower slice: commercial layout speed, residential sales, and free residential volume.
- If your work is research, policy, sensitivity analysis, or technology comparison, stay on SAM. Nothing below improves on it there.
Why Working Teams Outgrow SAM
SAM was scoped to a question. Given this technology, this resource dataset, and this financial structure, do the economics work over the project life? It answers that with published assumptions and open models, and the answer carries a national laboratory’s name.
An installer’s day asks a different question. What exactly goes on this specific roof, given that chimney, that parapet, that HVAC unit, and that setback? Then, what do I hand the inspector, and what does the customer sign?
Teams adopt SAM because it is free and authoritative. Six months later the pattern is visible. The array gets described once in SAM, then built again by hand in AutoCAD for the permit set, then described a third time in a proposal deck. Nothing carries forward. Our SAM review walks through that cost in detail.
So the ranking below is not about which tool models better. It is about which tools close the production gap SAM was never built to fill.
How These Six Were Ranked
Four tests decided the order, and they are weighted for a company that installs solar for a living.
First, does it produce a real layout on a real building, with obstructions resolved rather than assumed? Second, does it produce the drawings a permit office and a crew need? Third, does it produce something a customer signs? Fourth, what does a seat actually cost per year?
A tool that passes all four replaces the missing half of your workflow with one purchase. A tool that passes two is a good tool with a gap you will fill by hand or with a second subscription. Both outcomes are fine as long as you choose them knowingly.
None of these tools replaces SAM at what SAM is best at. Read the ranking as a list of production platforms, not as a verdict on NREL.
1. SurgePV, Best for Installers and EPCs
Who it is for. Installers and EPC design teams whose week is layout, shading, drawings, and proposals rather than sensitivity sweeps.
What it does that SAM does not. SurgePV is browser based and runs 8,760-hour simulation with module-level shading, mismatch, and string topology. That is the layer SAM leaves out. The array exists as geometry, so shading is a modelled result rather than a judgement call, and string topology is part of the model rather than a note on a drawing.
The bigger difference is downstream. Single-line diagrams and DWG export come out of the same model, and a white-label proposal layer sits on top of it. One array, one production number, three deliverables. Change a string configuration and the drawing and the proposal follow. That is the reconciliation labour that disappears.
Honest limitation. SurgePV is a design and delivery platform, not a techno-economic modeller. It does not do what SAM does on cash flow structures, incentive stacking, technology comparison across PV, CSP, wind and storage, or sensitivity analysis. If those questions are your job, SurgePV is the wrong purchase and SAM is the right one. Many teams run both.
Price. $1,299 to $1,899 per user per year. There is a live demo if you want to test it against one of your own projects rather than a slide.
2. PVsyst, Best for Bankable Yield
Who it is for. Teams whose yield number gets reviewed by a lender, an independent engineer, or an investment committee.
What it does that SAM does not. PVsyst carries acceptance. When financing depends on a production estimate, the reviewing engineer expects a PVsyst report, and a SAM output usually starts a conversation rather than ending one. That is a market convention rather than a technical verdict, but conventions decide deals. PVsyst also models near shading from a built 3D scene, so obstructions are geometry rather than an input assumption.
Honest limitation. It is a Windows desktop application with a demanding learning curve, and it stops at the yield report. No permit drawing set, no DWG for the drafter, no customer proposal. Teams that buy PVsyst for bankability still buy something else for production. The wider field sits in our PVsyst alternatives guide, and the engine comparison is in PVsyst vs SAM for bankable yield.
Price. Around $500 per user per year, which is modest for what it unlocks on financed work.
3. HelioScope, Best for Fast Commercial Layout
Who it is for. Commercial and industrial designers who need a credible rooftop layout and a module-level yield number quickly, often several times a week during bid season.
What it does that SAM does not. HelioScope turns a satellite image into a laid-out array with strings, wiring, and a module-level hourly simulation. The speed from address to defensible number is the product. SAM has no equivalent motion because it never held the building geometry in the first place.
Honest limitation. It stops short of the full deliverable set. There is no customer-facing interactive proposal, so most teams pair it with a second subscription for sales, and the permit drawing work still runs through a drafter. It is also a commercial tool by design, and residential reps find it heavy.
Price. Around $1,188 per user per year at the published entry level, with higher tiers above that.
4. Aurora Solar, Best for US Residential Sales
Who it is for. US residential installers running a sales-led motion, where the proposal is the product and the designer is often the closer.
What it does that SAM does not. Aurora builds a roof model from LIDAR and imagery, which gives pitch, azimuth, and obstruction geometry without a site visit. It then drives a polished customer-facing proposal with financing narrative from the same model. That path from address to signed document is the entire gap SAM leaves open for a residential business.
Honest limitation. It is the most expensive option here per seat, the deeper simulation features sit on the higher tiers, and it is not built for the commercial or utility work an EPC bench handles. Coverage quality also depends on the underlying imagery for a given address.
Price. $1,908 to $3,108 per user per year. Per-seat numbers across the field are collected in our solar design software pricing breakdown.
5. OpenSolar, Best Free Option for Residential Volume
Who it is for. Residential installers who want a design and proposal workflow without a per-seat licence line, especially teams with more reps than engineers.
What it does that SAM does not. OpenSolar covers the residential motion end to end. Roof design, production estimate, and a customer-facing proposal with financing options, at no cost at the seat. For a small installer moving from SAM plus spreadsheets plus a slide deck, that is an immediate upgrade with no procurement argument.
Honest limitation. Free at the seat means the business is funded elsewhere, through transactions and partner integrations in the marketplace around the product. That is a legitimate model, but it shapes the roadmap toward the flows that monetise. Engineering depth is also thinner than the paid tools here, and it is not the platform for commercial permit sets or bankable reporting.
Price. Free at the seat, transaction funded.
6. HOMER Pro, Best for Hybrid and Microgrid Architecture
Who it is for. Teams sizing a system with generation, storage, and often a generator or a grid connection, where the real question is architecture rather than roof layout.
What it does that SAM does not. HOMER optimises across a search space of component sizes and dispatch strategies. It answers how much PV, how much battery, and what control logic gives the lowest cost of energy for a given load profile. SAM models a configuration you specify well. HOMER hunts for the configuration you should have specified. For microgrid and off-grid work that difference matters.
Honest limitation. It is the least layout-oriented tool in this ranking. No roof geometry, no shading scene, no drawings, no proposal. It replaces the sizing question, not the production workflow, and it needs a genuine load profile to be worth running. Our HOMER Pro review covers where it fits.
Price. Quoted rather than published. Ask for a figure that matches your seat count and module set.
Comparison Table
| Tool | Best for | Price per user per year | Produces drawings | Produces a proposal |
|---|---|---|---|---|
| SAM (NREL) | Techno-economic analysis and sensitivity work | Free | No | No |
| SurgePV | Installers and EPCs needing one licence end to end | $1,299 to $1,899 | Yes, single-line diagram and DWG export | Yes, white label |
| PVsyst | Bankable yield a lender will accept | About $500 | No | No |
| HelioScope | Fast commercial layout with module-level simulation | About $1,188 | No | No |
| Aurora Solar | US residential sales with LIDAR roof modelling | $1,908 to $3,108 | Partial, sales and permit oriented output | Yes |
| OpenSolar | Free residential volume | Free at the seat, transaction funded | No | Yes |
| HOMER Pro | Hybrid and microgrid architecture | Quoted | No | No |
Try the software behind this review
Keep SAM for the analysis. Run the production work in a browser.
SurgePV runs 8,760-hour simulation with module-level shading, mismatch, and string topology, then produces the single-line diagram, the DWG, and the white-label proposal from the same model. One licence, one array, one number.
Book a free SurgePV demo →No credit card. 20-minute walkthrough on one of your own projects.
When You Should Not Leave SAM
This section matters more than the ranking, because for a large group of readers the right move is to stay.
Research work. If you publish, or if your results need assumptions a reviewer can audit, SAM’s open models and published methodology are the point. A commercial tool with a proprietary engine weakens the paper.
Policy and programme analysis. Modelling an incentive change across a technology mix is exactly the job SAM was funded to do. No design platform attempts it.
Sensitivity analysis. Sweeping an input and watching the return respond is where SAM earns its reputation. Knowing which assumption actually drives the outcome changes how you price a bid or negotiate a contract. None of the six tools above replaces this.
Technology comparison. PV against PV plus storage against something else entirely, inside one application, before anyone has drawn anything. That breadth is rare and it is free.
There is also no reason to choose. SAM costs nothing, so keeping it open alongside a design platform costs you only the learning curve. Use SAM to decide whether a project deserves engineering time, then use the design tool to decide what gets built.
What to Do If the Gap Is Drawings, Not Software
Some teams work through this list and find the honest answer is that no licence fixes their bottleneck. The design tool was never the constraint. The constraint is that stamped, coordinated construction drawings take longer than the sales team sells.
Buying a seat does not add drafting capacity. If that is your situation, our solar rooftop detailed engineering design bench produces the full construction pack against your standards and your AHJ. Look at a sample design pack first, then talk to our team with a live project rather than a hypothetical one.
Conclusion
- SAM is excellent and this list is not a criticism of it. Every tool here loses to SAM on techno-economic modelling, technology comparison, and sensitivity analysis.
- Rank on the gap you actually have. SurgePV closes the widest one for installers and EPCs, PVsyst closes the bankability one, and the rest each close a narrower slice.
- Most teams should run two tools, not one. Keep SAM for the viability question, and buy a production platform for the roof, the drawings, and the proposal.
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Disclosure and accuracy note
Commercial relationship. Heaven Designs and SurgePV are part of the same group. Treat our recommendation of SurgePV as a vendor making its own case, not an independent verdict. We have tried to describe every other product fairly, and to say plainly where a competitor is the better choice.
Pricing. All prices are indicative, compiled from public sources when this page was written. They vary by tier, region, contract term and exchange rate, and change without notice. Several vendors quote rather than publish, and some price in currencies other than the US dollar, so a converted figure moves with the exchange rate. Confirm current pricing with the vendor before you decide anything.
Trademarks and corrections. All product names and trademarks belong to their respective owners, and are used here for identification and comparison only. Their use does not imply affiliation with or endorsement by those companies. If anything here is out of date or wrong, tell us and we will correct it.
FAQ
What are the best alternatives to NREL SAM? For installers and EPCs, SurgePV first, because one licence covers 8,760-hour simulation with module-level shading, single-line diagrams, DWG export, and a white-label proposal. Then PVsyst for bankable yield, HelioScope for commercial layout speed, Aurora for US residential sales, OpenSolar for free residential volume, and HOMER Pro for hybrid architecture.
Is there a free alternative to SAM? OpenSolar is free at the seat and covers residential design and proposals, funded through transactions rather than licences. It is not a substitute for SAM’s analysis work, though. If your need is techno-economic modelling, SAM is already the free answer and nothing improves on it.
Why would anyone pay when SAM is free? Because the licence is not where the money goes. SAM produces no layout, no shading scene, no drawing set, and no proposal, so those artefacts get built by hand. That labour is a payroll cost nobody measures, and it usually exceeds a seat price within a few months of volume.
Can any of these replace SAM entirely? No, and none of them claims to. They replace the production half of the work SAM never covered. Sensitivity analysis, technology comparison across PV, storage and other technologies, and detailed financial structuring stay in SAM.
Which alternative do lenders accept? PVsyst is the market convention for financed work, and independent engineers expect to see it. Around $500 per user per year is a small line item next to a financing that stalls. The detail is in PVsyst vs SAM for bankable yield.
How much should a small installer budget for design software? A single production seat runs from free at the seat with OpenSolar, to roughly $1,188 for HelioScope, to $1,299 to $1,899 for SurgePV, up to $1,908 to $3,108 for Aurora. Add about $500 for PVsyst if lenders review your yield. The full per-seat picture is in our solar design software pricing guide.
Related: the full verdict in our SAM review, the bankability question in PVsyst vs SAM for bankable yield, the wider commercial field in PVsyst alternatives, the cost picture in solar design software pricing, and hybrid sizing in the HOMER Pro review.
