Singapore is the market where shading analysis matters most and is done worst. Almost every project is a rooftop surrounded by taller buildings, the sky is heavily diffuse, and most systems are sold on twenty-year power purchase agreements where the yield assumption is a contractual commitment. Get the shading wrong and the developer carries it for two decades.
Direct answer. The best solar shading analysis software in Singapore is PVsyst, because its 3D near-shading scene builder is the only widely used tool that models surrounding high-rise obstruction with the rigour a long PPA requires. SurgePV covers the same scene alongside the layout and single-line diagram for projects that need the full package from one license.
TL;DR
- Obstruction shading from neighbouring towers, not row shading, is the dominant Singapore loss.
- The sky is heavily diffuse, so blocked sky dome matters as much as blocked direct beam.
- On a 20-year PPA the shading assumption is a contractual commitment, not an estimate.
- Singapore redevelops. Model plausible adjacent development as a sensitivity.
- Near the equator, tilt optimisation matters little, so shading and soiling dominate the loss budget.
What Singapore Actually Changes About Shading Analysis
The obstruction is architectural. On a Singapore rooftop, the shading comes from neighbouring towers, plant rooms, lift overruns, and building services. These are large, close, and permanent. A model that only computes inter-row self-shading will miss the majority of the loss, and the error is not small: on a mid-rise building among taller neighbours, obstruction shading can remove a substantial share of morning or afternoon generation.
Diffuse dominates. Near the equator with high cloud cover and humidity, a large share of annual irradiance arrives as diffuse radiation from across the sky dome. That changes what shading means. A tall building does not just block the sun for two hours, it permanently removes a portion of the sky dome the array can see. Models that treat shading purely as a beam-blocking geometry problem underestimate the diffuse component of the loss, which is the opposite of the error most temperate markets make.
The number is contractual. Because most Singapore commercial solar is sold as a power purchase agreement, the yield underpinning the tariff is a twenty-year commitment. An optimistic shading assumption is not a marketing risk, it is a balance sheet risk carried by the developer for the life of the contract.
Redevelopment is a live risk. Singapore rebuilds aggressively. A rooftop unshaded today can be overlooked by a new tower within the contract term. Modelling a plausible adjacent development scenario is unusual practice and a genuine differentiator with a sophisticated buyer.
Tilt is not the lever. At one degree north, tilt optimisation yields very little. That means the loss budget is dominated by shading and soiling, and the design effort should follow.
The 7 Platforms Ranked for Singapore
| Platform | Best for | 3D obstruction scene | Diffuse sky treatment | Price per seat per year |
|---|---|---|---|---|
| PVsyst | Contract-grade shading studies | Best in class, scene builder | Best in class | ~$500 |
| SurgePV | Shading plus design and SLD | Yes, 8,760-hour | Yes | $1,299 to $1,899 |
| Aurora Solar | Complex roof and context geometry | Strong, LIDAR | Yes | $1,908 to $3,108 |
| HelioScope | Fast C&I layout and shading | Moderate | Yes | ~$1,188 |
| Scanifly | Drone capture of complex sites | Drone-derived | Inherited | ~$3,000+ |
| SketchUp plus Skelion | Bespoke context modelling | Manual | Manual | ~$700 plus plugin |
| SAM (NREL) | Sensitivity studies | Limited | Yes | Free |
PVsyst is the correct default. Its 3D near-shading scene builder lets you place the surrounding buildings explicitly and see the hourly consequence, and its output is what an independent engineer reviewing a PPA will expect. See PVsyst price.
SurgePV covers the same 8,760-hour modelling alongside string design, the single-line diagram, and DWG export for the Licensed Electrical Worker submission pack.
Scanifly is worth the cost on sites where the surrounding context is complex enough that drone capture beats manual modelling.
Try the software behind this guide
Put the neighbouring towers in the model, then price the PPA
SurgePV builds the 3D context, runs 8,760-hour shading against a diffuse equatorial sky, and carries the same model into the single-line diagram and DWG export.
Book a free SurgePV demo →No credit card. 20-minute walkthrough on one of your own projects.
What a Singapore Shading Deliverable Has to Contain
- 3D context model including every neighbouring structure tall enough to matter, at its real height and distance.
- Hourly shading loss across the full year, separated into obstruction and self-shading components.
- Diffuse sky loss quantified separately from beam blocking.
- Per-string or per-module loss table identifying positions that should be excluded.
- Redevelopment sensitivity modelling a plausible taller neighbour within the contract term.
- Yield basis for the PPA tariff, stating which shading case the tariff was priced against.
- Rooftop plant and services modelled as obstructions, not ignored.
Item 5 is the one that separates a serious Singapore proposal from a standard one. It costs an hour and it is the risk a twenty-year counterparty actually cares about.
Pricing in Singapore Dollars
| Stack | USD per year | Approx. SGD at 1.34 | Covers |
|---|---|---|---|
| PVsyst | ~$500 | ~S$670 | Contract-grade shading and yield |
| HelioScope | ~$1,188 | ~S$1,592 | C&I layout and shading |
| SurgePV | $1,299 to $1,899 | ~S$1,741 to S$2,545 | Shading plus full design |
| PVsyst plus SurgePV | ~$1,799 to $2,399 | ~S$2,411 to S$3,215 | Contract yield plus drawings |
Exchange rate is illustrative.
What Most Singapore EPCs Get Wrong
They model the roof and not the skyline.
It is the single most consequential error available in this market. A yield built from array geometry alone, with no surrounding context, overstates production on a large share of Singapore rooftops. On a PPA that error compounds for twenty years, and it surfaces in the first annual performance review when the developer is already committed to a tariff.
The second mistake is treating the diffuse component as a rounding error. In a sky this cloudy, a tall neighbour permanently removing a slice of the sky dome costs more than the direct-beam hours it blocks, and beam-only models miss it entirely.
When Software Is Not the Answer
Singapore rooftop projects routinely need a Professional Engineer’s structural assessment before any layout is meaningful, particularly on older buildings.
Our solar civil and structural engineering team produces those assessments with calculations delivered as STAAD Pro report calculations, and solar rooftop detailed engineering design covers the construction pack. See the sample design pack or talk to our team.
Conclusion
- Model the surrounding buildings explicitly. Obstruction, not row shading, is the dominant Singapore loss.
- Quantify the diffuse loss separately. A blocked sky dome costs more than the blocked beam hours in a cloudy equatorial climate.
- Run a redevelopment sensitivity on long PPAs. The skyline you priced may not last the term.
In this country series: solar software in Singapore, best solar design software in Singapore, best solar proposal software in Singapore, Pvsyst review. Tool deep dives: Helioscope review, Aurora Solar 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 Singapore? PVsyst, because its 3D near-shading scene builder models surrounding high-rise obstruction with the rigour a twenty-year PPA requires. SurgePV where the same license also has to produce the layout and single-line diagram.
Why is obstruction shading so important in Singapore? Because almost every rooftop sits among taller buildings. Obstruction from neighbouring towers routinely removes a larger share of generation than inter-row self-shading does.
How does the diffuse sky change shading analysis? Near the equator with heavy cloud, much of the irradiance arrives from across the sky dome. A tall neighbour permanently removes part of that dome, a loss that beam-only shadow models do not capture.
Should a PPA proposal model future development? It should. Singapore redevelops aggressively, and a taller neighbour appearing mid-term changes the yield the tariff was priced against. Modelling a plausible scenario is a genuine differentiator.
Does tilt optimisation help in Singapore? Very little. At one degree north the yield gain from precise tilt is small, which is why the loss budget is dominated by shading and soiling instead.
How much does solar shading analysis software cost in Singapore? From roughly S$670 per year for PVsyst alone to S$3,215 for a contract-grade yield plus drawings stack. Full math is in our solar design software pricing breakdown.
Related: the wider tool decision is in best solar design software in Singapore, and the method in how to do shadow analysis for solar rooftop projects.
