Belgium is one of the most densely built countries in Europe, and that is the fact that shapes shading analysis here. Terraced housing, narrow plots, and neighbours close on both sides mean near-field obstruction is the dominant loss on a large share of residential roofs. Add a diffuse North Sea sky and a latitude above 50 degrees, and a beam-only shadow model gets Belgian projects wrong in both directions at once.
Direct answer. The best solar shading analysis software in Belgium is PVsyst, because its near-shading scene builder handles the tight neighbour geometry of Belgian terraced housing and its sky-dome treatment suits a heavily diffuse climate. SurgePV covers the same hourly modelling alongside the layout and single-line diagram for the AREI-compliant connection pack.
TL;DR
- Dense terraced housing means neighbour and chimney shading dominates. Model in 3D, not with a horizon profile.
- The sky is heavily diffuse, so beam-only shadow models overstate the loss.
- Latitude above 50 degrees north makes winter shadows long.
- Installation follows the AREI wiring rules with connection under Synergrid C10/11 and an approved inspection.
- Regional policy differs between Flanders, Wallonia, and Brussels, so the value of a lost kilowatt-hour is not uniform.
What Belgium Actually Changes About Shading Analysis
Density is the defining constraint. Belgian residential stock is dominated by terraced and semi-detached housing on narrow plots. The neighbouring roof is often a few metres away and sometimes taller. At the latitudes involved, that produces long shadows across a substantial part of the array for a substantial part of the year. This is near-field obstruction, and a horizon profile method cannot see it at all. A proper 3D scene is not a luxury in this market, it is the minimum viable input.
The sky softens it. Belgian irradiance carries a high diffuse fraction. That means the neighbour’s gable removes less than the geometry implies, because a meaningful share of the resource arrives from across the sky dome rather than from the sun’s disc. Software that computes shading purely as beam blocking will produce pessimistic Belgian numbers and talk installers out of roofs that would have been fine.
Latitude still bites. Brussels sits above 50 degrees north. Winter solar elevation is low, so obstruction shadows are long through exactly the months when generation is scarce.
Connection follows a defined route. Installations are wired to the AREI rules with grid connection under the Synergrid C10/11 prescription and an inspection by an approved body before commissioning. No shading simulation method is prescribed, but the yield figure quoted to the customer is a commercial representation.
The regions differ. Flanders, Wallonia, and Brussels run different support and tariff arrangements, and they have moved at different times. That matters for shading because the value of a lost kilowatt-hour, and whether it matters when it is lost, depends on the regional arrangement the customer is under.
The 7 Platforms Ranked for Belgium
| Platform | Best for | Near-field 3D scene | Diffuse sky treatment | Price per seat per year |
|---|---|---|---|---|
| PVsyst | Detailed and financed studies | Yes, scene builder | Best in class | ~$500 |
| SurgePV | Shading plus design and SLD | Yes, 8,760-hour | Yes | $1,299 to $1,899 |
| PV*SOL premium | 3D shading visualisation | Best in class | Yes | ~€1,000+ |
| HelioScope | Commercial rooftop | Moderate | Yes | ~$1,188 |
| Aurora Solar | Complex roof geometry | Strong, LIDAR | Yes | $1,908 to $3,108 |
| SketchUp plus Skelion | Bespoke geometry | Manual | Manual | ~$700 plus plugin |
| SAM (NREL) | Sensitivity studies | Limited | Yes | Free |
PVsyst is the correct default. Its 3D near-shading scene builder is the right tool for a terrace with a taller neighbour, and its sky-dome handling keeps the number honest under a diffuse climate. See PVsyst price.
SurgePV runs 8,760-hour shading and carries the same model into string design, the single-line diagram, and DWG export.
PV*SOL premium produces the clearest customer-facing shading visualisation, which sells well on a roof where the neighbour is the problem.
Try the software behind this guide
Put the neighbour's gable in the model, then quote
SurgePV runs 8,760-hour shading against a full 3D scene of adjacent roofs and chimneys, then carries the same model into string design, single-line diagrams, and DWG export.
Book a free SurgePV demo →No credit card. 20-minute walkthrough on one of your own projects.
What a Belgian Shading Deliverable Has to Contain
- 3D obstruction scene covering adjacent roofs, gables, chimneys, dormers, and vegetation at real height and distance.
- Hourly shading loss with monthly breakdown, winter months explicit.
- Diffuse treatment stated, because beam-only models overstate the loss materially here.
- Per-string or per-module loss table identifying compromised positions.
- Optimiser payback calculation rather than a default recommendation.
- Self-consumption profile where the regional tariff arrangement makes timing matter.
- Annual production impact stated as a range against the unshaded case.
Item 1 needs real measurements. On a Belgian terrace the neighbouring roof height and the plot width are the two numbers that decide the answer, and estimating them from a satellite image is where most of the error in these studies comes from.
Pricing in Euro
| Stack | USD per year | Approx. EUR at 0.92 | Covers |
|---|---|---|---|
| PVsyst | ~$500 | ~€460 | Detailed shading and yield |
| PV*SOL premium | Quoted in EUR | ~€1,000+ | 3D shading plus workflow |
| HelioScope | ~$1,188 | ~€1,093 | Commercial layout and shading |
| SurgePV | $1,299 to $1,899 | ~€1,195 to €1,747 | Shading plus full design |
| Aurora | $1,908 to $3,108 | ~€1,755 to €2,859 | Sales-grade shading plus proposal |
Exchange rate is illustrative.
What Most Belgian Installers Get Wrong
They estimate the neighbour’s height from an aerial photograph.
On a Belgian terrace, the single most consequential input is how much taller the adjoining building is and how far away. A satellite view gives the footprint accurately and the height barely at all, and an error of a metre and a half on a plot this narrow moves the winter shading loss substantially. Measuring it properly takes a few minutes on site with a laser or a known reference, and it is worth more than any other refinement in the model.
The second mistake is treating the resulting shadow as opaque. Under a Belgian sky a large share of the resource is diffuse, so the shaded modules keep producing more than a hard-shadow model credits them with. Installers running beam-only tools decline positions that would have paid, and fit optimisers where the payback is not there.
When Software Is Not the Answer
If the constraint is planning permission, roof structure, or the inspection rather than the shading arithmetic, better modelling will not move it.
Our solar rooftop detailed engineering design and solar 3D pre-design services cover layout, structural coordination, and drawings, with sales-stage 3D and shading models turned around in 48 hours. See the sample design pack or talk to our team.
Conclusion
- Measure the neighbour, do not estimate it. On a narrow Belgian plot that height is the study’s most sensitive input.
- Use a diffuse-aware model. Beam-only geometry overstates the loss and costs viable sales.
- Run the optimiser payback. Under this sky the case is often marginal rather than automatic.
In this country series: solar software in Belgium, best solar design software in Belgium, best solar proposal software in Belgium, Helioscope review. Tool deep dives: Aurora Solar review, Opensolar 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 Belgium? PVsyst, because its near-shading scene builder handles tight terraced geometry and its sky-dome treatment suits a diffuse climate. SurgePV where the same licence also has to produce the design and drawings.
Why does Belgian housing density matter for shading? Because neighbouring roofs are often a few metres away and sometimes taller, producing long winter shadows across the array. That is near-field obstruction, which horizon profile methods cannot see.
Does the diffuse sky reduce the loss? Yes. A high diffuse fraction means an obstruction removes less than pure shadow geometry suggests, so beam-only models overstate Belgian shading losses.
Is a specific shading method required in Belgium? No. Installations follow the AREI wiring rules with connection under Synergrid C10/11 and an approved inspection, but no shading simulation is prescribed. The yield figure is still a commercial representation.
Do the regions change the analysis? They change what a lost kilowatt-hour is worth and whether its timing matters, because Flanders, Wallonia, and Brussels run different tariff arrangements. Report the loss profile, not just the annual total.
How much does solar shading analysis software cost in Belgium? From roughly €460 per year for PVsyst alone to €2,859 for Aurora’s higher tiers. Full math is in our solar design software pricing breakdown.
Related: the wider tool decision is in best solar design software in Belgium, and the method in how to do shadow analysis for solar rooftop projects.
