American shading analysis has a problem the rest of the world does not: the number has to satisfy two different audiences who want two different things. A homeowner wants to know how much the oak tree costs them. An incentive program administrator wants a Total Solar Resource Fraction figure produced by a method they accept. Those are not the same deliverable, and a tool that produces one convincingly does not automatically produce the other.
Direct answer. The best solar shading analysis software in the USA depends on what the number is for. For production modelling and customer proposals, SurgePV and Aurora both run hourly module-level shading from LIDAR-derived geometry. For an incentive program or utility submission requiring a measured solar access value, a site-measured instrument reading, historically the Solmetric SunEye class of device, is still what several administrators accept. PVsyst remains the reference for anything a lender reviews.
TL;DR
- Some US incentive programs specify how the solar access or TSRF value must be produced. Check before choosing a tool.
- Module-level hourly shading matters more in the US than in most markets because module-level power electronics are near-universal.
- NEC 690.12 fire access pathways change the array before shading does. Model the compliant layout, not the full roof.
- LIDAR-derived roof and obstruction geometry beats manual tracing on the complex roofs common in US residential.
- Tree growth over a 25 year term is a real modelling question that almost no proposal addresses.
What the United States Actually Changes About Shading Analysis
The measurement method can be prescribed. Several state and utility incentive programs have historically specified a minimum solar access percentage and, importantly, the method by which it must be established. Where a program names an instrument or a measurement procedure, a software-derived estimate is not a substitute regardless of how good the model is. This is the first question to ask on any US project touching an incentive, and it is the one buyers most often skip.
Module-level electronics change the loss. Because microinverters and DC optimisers are standard on US residential, a shaded module no longer drags its whole string. That means string-level shading models systematically overstate losses on US residential systems, sometimes substantially. A tool that models at module level, and knows the power electronics topology, produces a materially different and more accurate number.
Fire access pathways come first. NEC 690.12 rapid shutdown and the fire access pathway requirements in the applicable code edition remove roof area before any shading question arises. Running a shading study on the full roof plane and then applying setbacks afterwards produces a layout that will not be built. Model the compliant array.
Roofs are complicated. US residential roofs carry more planes, dormers, and penetrations than most markets. Self-shading from the building’s own geometry, chimneys, vents, and adjacent structures is frequently a larger loss than vegetation, and it needs 3D geometry rather than a horizon profile to capture.
Trees grow. A 25 year production estimate against today’s canopy is optimistic by construction. Very few US proposals model growth, and the ones that do have a genuine answer when the customer asks what happens in year ten.
The 7 Platforms Ranked for the US Market
| Platform | Best for | Module-level hourly | LIDAR geometry | Accepted for programs | Price per seat per year |
|---|---|---|---|---|---|
| SurgePV | Design plus shading in one license | Yes, 8,760-hour | Yes | Model-based | $1,299 to $1,899 |
| Aurora Solar | Residential sales-grade shading | Yes | Yes | Model-based | $1,908 to $3,108 |
| PVsyst | Lender and utility-grade studies | Yes, with scene | Import | Yes, for finance | ~$500 |
| HelioScope | C&I hourly shading | Yes | Partial | Model-based | ~$1,188 |
| Site-measured instruments | Program-specified solar access | Not applicable | Not applicable | Yes, where named | Hardware cost |
| Scanifly | Drone-captured obstruction geometry | Yes | Drone-derived | Model-based | ~$3,000+ |
| SketchUp plus Skelion | Bespoke or unusual geometry | Manual | Manual | No | ~$700 plus plugin |
SurgePV runs 8,760-hour module-level shading against the compliant array and carries it straight through to the single-line diagram and permit set, which removes the second modelling pass most teams run.
Aurora Solar produces the strongest customer-facing shading visualisation in US residential, which converts. See Aurora Solar pricing for the real all-in number.
PVsyst is the reference for anything a lender or independent engineer reviews, and its 3D near-shading scene builder is the right tool for complex obstruction geometry. See PVsyst price.
Scanifly earns its cost where roofs are complex enough that drone capture beats satellite geometry. See Scanifly pricing.
Try the software behind this guide
Module-level shading on the array you can actually build
SurgePV runs 8,760-hour module-level shading against an NEC-compliant layout, then carries the same model into the single-line diagram and AutoCAD DWG export.
Book a free SurgePV demo →No credit card. 20-minute walkthrough on one of your own projects.
What a US Shading Deliverable Has to Contain
- Compliant array layout with NEC fire access pathways applied before shading is assessed.
- 3D obstruction model including the building’s own geometry, chimneys, vents, adjacent structures, and vegetation.
- Hourly shading loss at module level, with the power electronics topology stated.
- Solar access or TSRF value produced by the method the incentive program specifies, where one applies.
- Per-module or per-string loss table, so the customer can see which positions are compromised.
- Annual production impact separated from the unshaded case, so the cost of the tree is explicit.
- Growth assumption where vegetation is close enough to matter over the term.
Item 4 is the compliance item. Items 3 and 6 are what win the sale, because a homeowner deciding whether to remove a tree needs the number attached to that specific decision.
Real Cost of the Shading Workflow
| Stack | Annual cost per seat | What it produces |
|---|---|---|
| Aurora only | $1,908 to $3,108 | Sales-grade shading plus proposal |
| SurgePV | $1,299 to $1,899 | Shading plus design plus permit set |
| HelioScope plus AutoCAD | ~$3,218 | C&I shading plus drafting |
| PVsyst | ~$500 | Lender-grade study only |
| Instrument | Hardware, one-off | Program-accepted measured value |
The consolidation argument is the same as elsewhere: if the shading model lives in a sales tool and the array gets redrawn in a design tool, the two disagree and somebody reconciles them by hand.
What Most US Installers Get Wrong
They model shading on the full roof plane, then apply setbacks.
The compliant array is smaller and differently shaped than the roof, and the modules that survive the fire access pathway requirements are frequently not the ones the unconstrained shading study favoured. The result is a production estimate built on an array that will never exist. Model the compliant layout first, then shade it.
The second mistake is quoting string-level losses on a system with optimisers or microinverters. That understates the system’s real performance and hands the sale to a competitor whose model was more accurate rather than more generous.
When Software Is Not the Answer
If an incentive program names a measurement method, no model satisfies it. If the constraint is that stamped permit sets are backing up behind the sales team, better shading software does not move that.
Our solar permit design service delivers PE-stamped NEC-compliant plan sets in 4 to 7 business days across all 50 states, and solar 3D pre-design turns a site into a sales-stage 3D and shading model in 48 hours. See the sample design pack or talk to our team.
Conclusion
- Check the program’s required method before choosing a tool. A model does not substitute for a prescribed measurement.
- Shade the compliant array, not the roof. NEC access pathways change the layout before shading does.
- Model at module level. With optimisers and microinverters near-universal in US residential, string-level losses overstate the damage.
In this country series: solar software in the USA, best solar design software in the USA, best solar proposal software in the USA, Opensolar review. Tool deep dives: Pvsol review, Pvcase review.
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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 is the best solar shading analysis software in the USA? SurgePV or Aurora for hourly module-level modelling on residential and C&I, PVsyst for anything a lender reviews, and a site-measured instrument where an incentive program specifies the measurement method.
Do US incentive programs accept software shading estimates? It varies. Some programs specify how the solar access value must be established, including naming a measurement procedure. Confirm the requirement before relying on a model-derived figure.
What is TSRF? Total Solar Resource Fraction, the share of the available solar resource a given array position actually receives after shading and orientation losses. Several US programs have used it as a qualifying threshold.
Does module-level shading modelling really matter? In US residential, yes. With microinverters or DC optimisers, a shaded module does not drag its whole string, so string-level models overstate the loss, sometimes substantially.
Should shading be modelled before or after NEC setbacks? After. Fire access pathway requirements remove roof area and change the array shape, so a study on the full roof plane describes a system that cannot be built.
How much does solar shading analysis software cost in the USA? From roughly $500 per year for PVsyst alone to $3,108 for Aurora’s higher tiers. Full cross-platform math is in our solar design software pricing breakdown.
Related: the wider tool decision is covered in best solar design software in the USA, and the method itself in how to do shadow analysis for solar rooftop projects.
