Best Solar Shading Analysis Software Singapore 2026

If you are choosing solar shading analysis software in Singapore, start by throwing away the row spacing worksheet. Singapore sits at 1.35 degrees north. Solar noon elevation here never drops below roughly 65 degrees in any month, so shadow multiples are tiny and inter-row self-shading is close to a solved problem before you open a tool. What replaces it is a shading problem almost no global platform was designed for: extreme vertical density. There is effectively no residential market, PV goes onto HDB block roofs, industrial roofs in Jurong and Tuas, reservoirs and increasingly facades, and the object casting the shadow is usually a taller building that belongs to somebody else. Sometimes it is a building that has not been built yet. The tool that wins our 2026 bench test is SurgePV at about SGD 1,730 (US$1,299) per user per year, and this guide ranks ten shading tools in Singapore dollars with the arithmetic behind the ranking.

Direct answer. The best solar shading analysis software in Singapore for 2026 is SurgePV, at about SGD 1,730 (US$1,299) per user per year on the 5-User Team plan. It runs an 8,760-hour module-level shading engine with anisotropic sky modelling, builds obstruction geometry from satellite imagery in under 60 seconds, and lets you add a neighbouring building at any specified height as its own scenario, which is the capability the Singapore market actually needs. PVsyst still wins where a lender names the tool, and Ladybug on Rhino wins on facade physics.

This guide is for Singapore EPCs, consultants tendering into SolarNova, and design teams whose yield numbers are being challenged in a technical review. It gives the sun-angle arithmetic first, then the vertical-density problem that carries this market, then the ranking.

Why 1.35 Degrees North Removes the Row Spacing Problem

Shading physics is identical everywhere. What varies by latitude is which term dominates the answer. Solar noon elevation is 90 degrees minus the absolute difference between latitude and solar declination, and at 1.35N that difference stays small in every month of the year.

The full year at 1.35N looks like this. On 21 December, declination is 23.44 degrees south, so the angular gap is 24.79 degrees and solar noon elevation is 65.2 degrees. On 21 June, declination is 23.44 degrees north, the gap is 22.09 degrees and elevation is 67.9 degrees. At the equinoxes the sun passes within 1.4 degrees of the zenith. There is no low-sun season. The tangent of 65.2 degrees is 2.16, so one metre of array height casts 0.46 m of shadow at the single worst noon of the year, against 3.99 m at Berlin latitude. That is a factor of nearly nine.

The consequence is worth stating bluntly, because it is the opposite of what most imported design templates assume. In Singapore, row pitch is decided by maintenance access, wind uplift and thermal airflow, not by shading geometry. If your tool’s headline feature is inter-row optimisation, it is optimising a term that is already small. The global pillar on solar shading analysis software covers the engine mechanics that apply in every market. This page covers what actually changes at 1.35 degrees north.

Inter-Row Spacing at 1.35N: The Arithmetic

Solar noon is the easy case. A real spacing rule protects a design window, conventionally 9 am to 3 pm solar time on the worst day, because the sun is both lower and swung further east at 9 am. The row-direction shadow is height divided by the tangent of solar elevation, multiplied by the cosine of the sun’s azimuth measured from due south.

At Singapore on 21 December at 9 am solar time, solar elevation is about 39.7 degrees and the sun sits about 57.5 degrees east of south. That gives a row-direction shadow of 0.65 m per metre of array rise, against 0.46 m at noon. So the 9 am case governs, and it is still small.

Put a real module on that. A 2.28 m module in portrait on a flat concrete roof:

Configuration	Array rise	Singapore min pitch	Berlin-latitude min pitch (noon)	Ground coverage ratio
2.28 m portrait, 10° tilt	0.40 m	2.50 m	3.82 m	0.91
2.28 m portrait, 15° tilt	0.59 m	2.58 m	4.55 m	0.88
2.28 m portrait, 20° tilt	0.78 m	2.64 m	5.25 m	0.86
1.13 m short side, 10° tilt	0.20 m	1.24 m	1.90 m	0.91

On a 40 m deep logistics roof in Tuas at 15 degrees tilt, Singapore geometry fits 15 rows where the European template fits 8. That is not a rounding error, it is nearly double the installed capacity on the same slab, and the client never sees the modules that were never proposed. Ground coverage ratios of 0.86 to 0.91 are entirely normal at this latitude and should not be flagged as aggressive by a reviewer.

The tilt angle entry covers the underlying term, and the Singapore design software guide covers the multi-plane layout side in detail. Tilt optimisation is also a weak lever here: at 1.35N with a diffuse fraction above 55 percent, the annual yield difference between 5 and 15 degrees is small, and the tilt decision is really about drainage and self-cleaning.

Vertical Density Is the Singapore Shading Problem

This is the variable that carries this market. Singapore has roughly 730 square kilometres of land and builds upward as a matter of national policy. There is close to no residential PV market in the detached-house sense, so almost every array sits on an HDB block roof under the SolarNova programme, an industrial or logistics roof, a car park deck, a reservoir or a facade. In every one of those settings except the reservoir, the dominant shading object is a building, and often it is not the building you are working on.

Two distinct problems live under this heading. The first is adjacent-tower shading, where a neighbouring block or a commercial tower on the next parcel cuts across the array. The second is self-shading within a cluster, where an HDB precinct puts a dozen 12 to 25 storey blocks in a regular grid and every block shades its neighbour in the early morning and late afternoon. Both are geometric, both are permanent, and neither is helped by string re-grouping once the array is already in the shadow.

The arithmetic is unforgiving because a tall object casts a long shadow even at a high sun angle. Using the Singapore factors of 0.46 m per metre at December noon and 1.20 m per metre at 9 am December, along the sun’s direction:

Adjacent structure	Height above array	December noon shadow	9 am December shadow
Parapet wall	1.0 m	0.46 m	1.20 m
Lift motor room or water tank	3.5 m	1.62 m	4.21 m
Adjacent 12-storey HDB block	36 m	16.7 m	43.3 m
Adjacent 25-storey block	75 m	34.7 m	90.2 m
Adjacent 40-storey CBD tower	140 m	64.8 m	168.4 m

A 25-storey neighbour sterilises 35 m of roof at the mildest hour of the mildest day, and 90 m in the morning. No sky model, string layout or module technology recovers that. The design decision is where the array goes and whether the project is viable at all, and it has to be made in the first hour, not in the loss diagram at the end.

The practical instruction that follows is about how you build the scene. On a Singapore site, the neighbouring buildings are not context, they are the primary geometry. A tool that lets you trace a roof beautifully but makes adding a 75 m block next door awkward will cost you more time than it saves. Ask any vendor to model one real HDB precinct with six neighbouring blocks at their true heights during the trial, and time it.

Future-State Shading: Modelling the Tower That Is Not Built Yet

Here is the requirement that separates Singapore from almost every other market on this cluster, and it is the reason a shading study here has a shelf life.

Singapore redevelops fast. A two-storey light industrial shophouse row, a low-rise carpark or an older block can be replaced by something far taller inside the 25 year life of a PV asset. If you model the current skyline and sign a generation guarantee against it, you have underwritten a risk you did not price. We have seen commercial rooftop arrays lose a meaningful share of morning production because the adjacent parcel went vertical in year six.

The useful thing about Singapore is that this risk is knowable in advance, which is not true in most cities. The Urban Redevelopment Authority Master Plan publishes the zoning, gross plot ratio and building height controls that apply to each parcel. That means you can read the permitted envelope of the plot next door and model the worst legally buildable case, not a guess.

The Future-State Shading Check. This is our named framework for Singapore sites, and it is four steps:

1. Pull the Master Plan zoning and height control for every parcel within 150 m of the array. At 1.20 m of shadow per metre of height in the 9 am December case, a 100 m height control reaches 120 m, so 150 m is a sensible catchment for a rooftop and more for a facade.
2. Build two scenes, not one. Scene A is the skyline as built today. Scene B replaces every adjacent low-rise parcel with a block at its permitted envelope. Run both through the same 8,760-hour engine.
3. Report the delta as a range, not a single number. The honest output is “1,145 kWh per kWp today, 1,062 kWh per kWp if the north-east parcel builds to its permitted height”, which is a sentence a facility owner and a lender can both act on.
4. Decide what the contract says. If you are guaranteeing generation, the guarantee should reference Scene A with a defined carve-out for third-party construction, or it should be underwritten against Scene B. Quietly assuming Scene A is where the money is lost.

That workflow needs one specific software capability: the ability to place an arbitrary rectangular volume at a stated height and azimuth, save it as a named scenario, and diff two scenarios. It is a modest feature. Most PV tools do not have the scenario layer, and you end up maintaining two project files by hand.

Get your shading numbers sanity-checked. For an independent second opinion on a disputed yield or a future-state scenario before it reaches your client, talk to our engineering team.

Facade and Vertical Surface Irradiance at the Equator

Building-integrated and facade-mounted PV is a live conversation in Singapore in a way it is not in most markets, because the roof area is exhausted long before the demand is. It is also the case where the standard PV shading tool is at its weakest, and where the equatorial sun angle produces a result that surprises people.

At 1.35N a vertical surface is a poor collector for beam radiation, because the sun spends most of the day high overhead and strikes a wall at a glancing incidence angle. A vertical plane in Singapore typically receives somewhere in the region of 35 to 45 percent of the annual irradiance that a horizontal plane receives, before any shading. That is the first thing to tell a client who has read about facade PV in a European case study, because at Berlin latitude a south wall does far better relative to horizontal.

The second result is more useful. Near the equator the sun rises close to due east and sets close to due west all year, and it moves steeply, so east and west facades outperform north and south facades. A north or south wall only receives direct beam for the part of the year when the sun’s declination puts it on that side of the zenith, roughly April to September for a north wall and October to March for a south wall. That is the reverse of the temperate intuition every architect brings to the meeting, and getting it wrong changes which elevation gets the modules.

The modelling requirement follows from those two facts. On a facade in a dense cluster, the dominant terms are not beam at all, they are the sky view factor from a canyon-like street, the diffuse component, and inter-reflection from the glass and painted surfaces of surrounding towers. Reflected irradiance off a neighbouring curtain wall is a real gain, and it is highly directional. A PV tool that applies a single ground albedo of 0.2 and an isotropic sky to a vertical plane is not modelling this building. That is precisely the case where a Radiance-based environmental engine such as Ladybug and Honeybee on Rhino and Grasshopper earns its place, because it traces inter-reflection between surfaces properly. See the diffuse horizontal irradiance definition for the underlying quantity.

Floating Solar on Reservoirs: The Opposite Problem

Singapore’s reservoir arrays at Tengeh, Kranji, Bedok and Lower Seletar invert everything above. On open water the horizon is close to zero. There is no adjacent tower, no lift motor room, no parapet. The perimeter bund and the treeline around a reservoir subtend a low angle from most of the array, and at a latitude where the sun clears 65 degrees at the worst noon, a 15 m treeline 80 m away is simply not a shading object for most hours.

That leaves three shading terms and only three:

• Inter-row self-shading on the floats. Floating structures usually sit at a low tilt, commonly 5 to 12 degrees, partly for wind loading and partly for float geometry. At 1.35N with a rise of 0.2 to 0.5 m, the required pitch is well under a metre, so this is genuinely small.
• Perimeter and bund shading on the outer rows only. This is a boundary effect and it should be reported as such, not smeared across the whole array as an average.
• Mooring-driven tilt and heading variance. A float platform moves. Wind and mooring tension change the effective tilt and azimuth of the modules by a degree or two, and that is not shading at all, it is an incidence angle effect that most rooftop engines cannot represent.

The reason this matters commercially is that a shading study on a floating project should come back nearly empty, and if it does not, someone has applied a rooftop template. Where the modelling effort should actually go on a floating project is the water-cooling gain on cell temperature, the higher soiling from bird activity, and the mooring layout. Our floating solar design software guide covers the tools that handle those, and it is honest that most rooftop platforms, including SurgePV, do not.

The 5-Point Singapore Shading Bench Test

This is the framework we score shading tools on before deploying them, adapted to Singapore conditions. Five axes, ten points each, out of 50. We do not deploy below 38.

1. Tall-neighbour geometry and speed. How fast can you place six adjacent blocks at true heights and get a module-level result. Highest weight of the five in this market, because this is the dominant loss term.
2. Scenario handling for future state. Named, saved, diffable scenarios so Scene A and Scene B can sit in one project. Almost nobody scores well here.
3. Vertical and facade surface support. Irradiance on a wall plane with a defensible treatment of sky view factor and reflected components, not a flat albedo.
4. Sky model quality. Anisotropic transposition (Perez or Hay-Davies) with the model named in the report. Under a diffuse fraction above 55 percent, an unstated isotropic default misprices any module with a restricted sky view.
5. Cost per finished shading study in SGD, including add-on tiers and scene-building time.

Scores: SurgePV 44, PVsyst 44, Ladybug on Rhino 38 (with a heavy caveat on PV workflow), HelioScope 38, PV*SOL Premium 38, Aurora Solar 33, Solmetric SunEye 32, Solargis 30 as a data layer rather than a shading engine, Meteonorm with PVGIS horizon 27, Scanifly 30. The scoring is ours and it is opinionated.

PVsyst and PVSOL both gained a point on axis five once we re-checked the vendors’ own published prices in August 2026. PVsyst Professional is CHF 700 per user per year and PVSOL Premium is EUR 845 per named user per year, both of which are cheaper per seat than SurgePV at US$1,299. PVsyst therefore ties SurgePV on total score, and SurgePV keeps the top slot only on axes one and two, the speed of building a six-block precinct and the ability to save and diff a future-state scenario. If your bottleneck is budget rather than scene-building time, buy PVsyst.

Top 10 Solar Shading Analysis Software in Singapore Compared

Pricing is each vendor’s own published 2026 list price, quoted in the currency the vendor bills in. Where an SGD figure is shown it is an approximate conversion at about SGD 1.33 per US dollar and it moves with the exchange rate.

#	Tool	Published price	Shading capability	Best for
1	SurgePV	US$1,299/user/yr (about SGD 1,730)	8,760-hr module-level, anisotropic sky, fast adjacent-block scenes	EPCs running shading on every HDB and industrial quote
2	PVsyst	CHF 700/user/yr, Professional	Reference near-shading 3D scene and loss diagram	Lender and SolarNova technical due diligence
3	HelioScope	Basic US$159/mo (US$1,620/yr); Pro US$259/mo (US$2,640/yr)	Module-level C&I yield with clean loss tree	Consultancies delivering industrial yield reports
4	PV*SOL Premium	EUR 845/named user/yr + VAT	3D shading animation and shade frequency visual	Persuading a facility owner, offline work
5	Ladybug and Honeybee on Rhino	Free plugin, Rhino ~SGD 1,325 one-time	Radiance-grade facade irradiance and inter-reflection	Facade and BIPV studies in a dense cluster
6	Aurora Solar	Basic US$135/user/mo billed annually (US$159 monthly); Premium US$220 (US$259 monthly)	Irradiance maps, LIDAR and bankable shade reports on Premium	Teams also serving US clients
7	Solargis	Prospect Basic EUR 2,400/yr; Prospect Professional EUR 4,800/yr	Satellite irradiance and diffuse fraction data layer	Getting the sky input right
8	Solmetric SunEye 210	US$2,195 base, North America	Measured on-roof skyline, no modelling assumption	Dense sites and disputes over a neighbour
9	Meteonorm with PVGIS horizon	Meteonorm CHF 675 single licence, PVGIS free	Far-horizon profile as a model input	Cheap sanity check on the distant skyline
10	Scanifly	Not publicly listed, quote only	Drone photogrammetry as-built capture	Complex industrial roofs, subject to airspace

Say the obvious thing about that table before anything else: PVsyst is cheaper than SurgePV. CHF 700 per user per year means five PVsyst seats cost CHF 3,500 against US$6,495 for five SurgePV seats, and PV*SOL Premium at EUR 845 per named user is cheaper again per seat than we are. SurgePV holds first place here on scene speed and scenario handling for tall neighbours, not on price.

Positions 1 to 5 are engines. Positions 6 is an engine with a weaker local fit. Positions 7 and 9 are data layers. Positions 8 and 10 are capture and measurement instruments that feed an engine. In Singapore, position 10 carries a specific caveat: much of the island sits inside controlled airspace and drone operations need approval, so plan a Scanifly workflow around that rather than assuming it.

1. SurgePV

What it does best for Singapore shading. SurgePV runs 8,760-hour module-level shading with bypass-diode physics on every paid plan, with no add-on tier. Sky transposition is anisotropic and the model is stated in the report. The capability that matters most here is scene speed on tall neighbours: the AI 3D roof pulls the subject building from satellite imagery in under 60 seconds, and adjacent volumes go in as arbitrary blocks with a typed height, so a six-block HDB precinct at true heights is a coffee-break job rather than an afternoon. Scenarios can be saved and compared, which is what makes the future-state workflow above practical rather than theoretical. The annual heatmap colours each module by percent irradiance loss and drives MPPT grouping directly, and the loss tree keeps shading, soiling and thermal on separate editable lines. A 1 MW industrial roof simulates in under five minutes.

Pricing. SGD 1,730 (US$1,299) per user per year on the 5-User Team plan, roughly SGD 8,650 for five seats. Individual seats about SGD 2,530. Free trial, no credit card.

Who it suits. Singapore EPCs and consultants who want a shading study on every commercial quote and a defensible future-state scenario on anything carrying a generation guarantee.

Honest limitations. Four concrete ones, and two of them bite specifically in Singapore. First, floating PV is a genuine gap. SurgePV treats a floating array as a fixed-tilt plane. It does not model mooring layout, wave and wind-driven tilt variance, or the water-cooling gain on cell temperature, so Tengeh-scale reservoir work needs a specialist workflow or PVsyst alongside it. Second, facade and vertical-surface handling is shallow. You can place a vertical plane and get an irradiance figure, but the engine applies a simple albedo rather than tracing inter-reflection between surrounding curtain walls, so a dense CBD facade study belongs in Ladybug or Honeybee and not here. Third, future-state scenarios are manual: there is no URA Master Plan import, so you read the height control yourself and type it in. Fourth, it is cloud-only, so there is no offline mode, and brand recognition is thin because the product launched in 2025, which means a technical adviser who has read PVsyst loss diagrams for a decade will ask an extra question about provenance.

Book a SurgePV demo and bring a real HDB precinct or a Jurong roof with a taller neighbour, so you can judge the adjacent-block handling rather than a clean showcase file.

2. PVsyst

What it does best. PVsyst is the reference. Its near-shading 3D scene editor is the most complete obstruction geometry implementation available, it handles a complex cluster of adjacent volumes correctly, and its loss diagram is the artefact that technical advisers and lenders read fluently. On lender-named bankability, PVsyst beats SurgePV outright, and on a large SolarNova or industrial financing that is the deciding factor.

Pricing. CHF 700 per user per year for the Professional edition, sold as an annual subscription rather than a perpetual licence. Education is CHF 420, Training and Research CHF 560, and group discounts of 5 to 20 percent apply by quantity. That is cheaper per seat than SurgePV.

Honest limitations. Building the near-shading scene is slow, commonly an hour or more for a dense HDB precinct, which is exactly the Singapore case. It has no scenario diff, so a future-state study means two project files maintained by hand. Windows desktop only, no proposal output, no client-facing heatmap. Heaven Designs’ guide to reading a PVsyst loss diagram is the fastest way in.

3. HelioScope

What it does best. Module-level 8,760-hour simulation with a readable loss tree that separates shading from soiling, mismatch and thermal. For a 2 MW Tuas logistics roof, a HelioScope report is accepted by Singapore technical reviewers without argument, and the loss tree makes the shading share visible rather than buried inside a single number.

Pricing. Basic is US$159 per month, US$1,620 a year, for one user and 10 projects a month, with a 1.25 MW DC design cap. Pro is US$259 per month, US$2,640 a year, and lifts the cap to 5 MW. Five Basic seats come to about US$8,100 a year, roughly SGD 10,800.

Honest limitations. Obstruction modelling is manual with no AI roof build, so a dense cluster takes real drafting time. Vertical facade planes are not a supported design case. No proposal tooling, no local regulatory content, and per-seat monthly pricing scales badly as a team grows. See our HelioScope alternative comparison.

4. PV*SOL Premium

What it does best. The 3D shading animation is the best client-facing shading artefact on the market. It renders shadow movement across the array through the day and year plus a per-module shade frequency visual. When a facility manager insists the block across the service road is not a problem, this settles it in one screen, and in Singapore that conversation happens on most sites. It also runs entirely offline.

Pricing. EUR 845 per named user per year plus VAT for PVSOL Premium, with standard PVSOL at EUR 585. This is now a user-based subscription and not a perpetual licence: Valentin Software stopped selling perpetual licences on 19 November 2024 and maintenance renewals on older perpetual licences ended on 1 October 2024, though existing perpetual licences remain usable. At EUR 845 a seat it is cheaper than SurgePV.

Honest limitations. Windows desktop only, single user, a dated interface, manual 3D scene building, a component library thin on the Chinese modules commonly specified here, and support hours that do not align with Singapore working days.

5. Ladybug and Honeybee on Rhino and Grasshopper

What it does best. This is not a PV tool, it is an environmental analysis toolkit that wraps Radiance and EnergyPlus, and it is on this list for one specific Singapore reason: facade and vertical-surface irradiance in a dense cluster. Ladybug computes annual irradiance on any surface with a proper sky decomposition, and Honeybee runs Radiance so inter-reflection between a neighbouring curtain wall and your facade is traced rather than approximated with a single albedo. For a BIPV feasibility study on a tower surrounded by other towers, nothing on this list is close. It is also free and open source, so the cost is the Rhino licence and the learning curve.

Pricing. The toolkit is free. Rhino is roughly SGD 1,325 as a one-time commercial licence, Grasshopper is included.

Honest limitations. It produces irradiance, not energy. There is no module database, no string sizing, no inverter model, no loss tree, no P50 or P90 report and nothing a lender will read. It requires real competence in Grasshopper, so it lives with the architect or the facade consultant rather than the PV designer. Treat it as an input to a PV model, never as a substitute for one.

6. Aurora Solar

What it does best. Strong irradiance mapping and a capable shade engine, with good LIDAR-backed roof detection where LIDAR exists. For a Singapore team doing design outsourcing for US installers, Aurora fluency is a commercial asset in itself.

Pricing. Basic is US$135 per user per month billed annually, US$159 billed monthly. Premium is US$220 annually, US$259 monthly. Both cover one user and 50 projects a month, Enterprise is quoted, and plan sets are a separately priced service rather than something any plan includes. Site models start at US$9.99. Aurora Basic at US$1,620 a year undercuts a SurgePV Individual seat at US$1,899.

Honest limitations. The product is built around a detached-house market that Singapore does not have, so much of the workflow is dead weight here. LIDAR coverage is limited locally, so the feature that makes Aurora excellent in California degrades to manual tracing. The features you would buy it for on this page, LIDAR modelling and bankable shade reports, sit on Premium rather than Basic. See our Aurora Solar alternative writeup.

7. Solargis

What it does best. Solargis is a satellite-derived irradiance data service rather than a shading tool, and it is here deliberately. In a market where the diffuse fraction runs above 55 percent, the quality of the direct and diffuse split feeding your model changes the answer more than the choice of engine does. Solargis time series carry a documented uncertainty band that technical advisers accept.

Pricing. Solargis publishes plan pricing, not a per-site price. Prospect Basic is EUR 2,400 a year for 500 projects and five users, Prospect Professional is EUR 4,800 a year, and Evaluate is EUR 12,000 a year for 60 early-stage projects. Prospect Enterprise and the Time Series API are not publicly listed. Any per-site figure you are shown is a negotiated quote rather than a published rate.

Honest limitations. It runs no shading geometry, no module physics and no yield model, so it is a purchase alongside a design tool rather than instead of one. On a single small rooftop job an annual Prospect subscription is hard to justify against free typical meteorological year data.

8. Solmetric SunEye 210

What it does best. A handheld fisheye skyline instrument. You stand at a point on the roof, take one capture, and it returns measured sky obstruction and monthly solar access for that exact position with no modelling assumption in the answer. On a Singapore roof surrounded by blocks, a measured skyline is the strongest single piece of evidence you can hold in a dispute.

Pricing. US$2,195 base for North America, about SGD 2,920, as capital equipment, and that price includes a lifetime PV Designer licence. The SunEye 210 is a current product, not a discontinued one: Solmetric has been a Fluke company since the acquisition announced in September 2023 and still sells it new. As of 2 August 2026 it is out of stock with a stated 10 to 12 week lead time, so order well ahead of the project.

Honest limitations. It measures points, not arrays, so a large roof needs many captures and interpolation. Critically for Singapore, it cannot measure a building that has not been built yet, which is exactly the risk this market carries. Roof access is required, the current lead time is 10 to 12 weeks, and servicing routes abroad.

9. Meteonorm with a PVGIS Horizon Workflow

What it does best. This is the cheapest defensible way to get the far horizon into a model. PVGIS publishes a terrain-derived horizon profile for any coordinate free of charge, and Meteonorm lets you attach a horizon profile to a generated weather file so the far shading is baked into the irradiance series before the near-shading engine ever runs. In Singapore the terrain horizon is close to flat, which is itself worth documenting, and the same workflow is genuinely useful for a regional team modelling sites in Malaysia or Indonesia.

Pricing. Meteonorm publishes CHF 675 for a single perpetual licence and CHF 350 for each additional licence, billed in Swiss francs (about SGD 1,080 at CHF 1 to SGD 1.60, approximate and rate-dependent). PVGIS is free.

Honest limitations. A horizon profile is far shading only. It carries no near objects, no buildings, no module-level detail and no bypass diode behaviour, so on a Singapore rooftop it addresses the term that matters least. Use it as a data input and nothing more.

10. Scanifly

What it does best. Drone photogrammetry that turns a short flight into an accurate as-built 3D model with every obstruction at its real height, including the neighbours. On a congested industrial roof where a physical survey is slow and a guessed height is the biggest error in the model, this removes the guess.

Pricing. Scanifly does not publish a price list. Pricing is quoted, and it scales with team size and capture volume, so budget from a quote rather than from a figure in a software directory.

Honest limitations. It captures, it does not simulate, so you still export into an engine that runs the physics. In Singapore the practical constraint is airspace: large parts of the island are within controlled or restricted zones and drone operations require permits, so a workflow that assumes a flight on demand will not survive contact with the schedule.

Is a Shading Report Required in Singapore?

Plainly: no. There is no statutory or regulatory requirement for a shading study on a Singapore solar project. Unlike the UK, where the MCS Standard Estimation Method defines a shading factor inside a regulated calculation, Singapore rules do not name one. The Energy Market Authority sets the licensing and market framework and SP Group runs the physical connection, metering and turn-on, and neither requires a shading analysis. We are not going to invent a requirement.

The pressure is commercial and contractual, and it is stronger here than the absence of regulation suggests:

• SolarNova and public-sector tenders. Aggregated rooftop tenders are competitive on price per kWh delivered, which makes the yield assumption the bid. A shading study is how you defend it in the technical evaluation.
• Rooftop lease and PPA structures. Most Singapore commercial rooftop work is a lease or a power purchase agreement rather than an outright sale, so the developer carries the generation risk for 20 years or more. That makes the future-state shading scenario a pricing input, not documentation.
• Lender and technical adviser review. Project finance asks for P50, P75 and P90 bands from a recognised engine with shading as an explicit loss line. This is where PVsyst’s name still carries weight.
• Client disputes. A generation shortfall in month three is the commonest complaint, and a shading heatmap attached to the contract is the difference between a conversation and a credit note.

For market context, the IEA and IRENA country trackers carry deployment data, and the Meteorological Service Singapore publishes the cloud and sunshine-duration records behind the diffuse fraction figures used above.

Mistakes Singapore Designers Make in Shading Analysis

1. 1
   Carrying European row pitch onto a 1.35N roof. A 4.55 m pitch where 2.58 m is correct costs a Tuas logistics roof close to half the capacity it could carry, and the client never sees the difference.
2. 2
   Modelling the skyline as it stands today. On a 25 year asset in a city that redevelops continuously, the current skyline is a snapshot. Pull the Master Plan height control for the adjacent parcels and run the permitted envelope as a second scenario.
3. 3
   Ignoring self-shading between blocks in an HDB cluster. A regular grid of 12 to 25 storey blocks shades itself every morning and evening. Model the whole precinct, not the single block you were given.
4. 4
   Applying temperate facade intuition. At the equator a vertical plane collects roughly 35 to 45 percent of horizontal irradiance, and east and west elevations beat north and south. Putting the modules on the wrong wall is a design error made in the first meeting.
5. 5
   Running a rooftop shading template on a floating array. A reservoir has a near-zero horizon. If the study comes back with a meaningful shading loss, check what geometry was imported before you believe it.
6. 6
   Accepting an unstated isotropic sky model. With a diffuse fraction above 55 percent, an isotropic assumption over-penalises modules with a blocked horizon and under-penalises modules with a blocked zenith, which misranks two competing layouts against each other.
7. 7
   Grouping shaded and unshaded modules on one MPPT. Inter-building shading in Singapore is concentrated in the morning and evening hours and affects predictable parts of the roof. Group the strings to match the geometry. The QBits Energy comparison of dual and single MPPT covers the tradeoff.

Should a Singapore Team Standardise on SurgePV for Shading?

For most Singapore EPCs the sensible shape is one primary engine for the rooftop pipeline, PVsyst kept in reserve for bankability packs, and a facade specialist brought in per project rather than licensed permanently.

How Heaven Green Energy Helps

Heaven Green Energy is a solar EPC with more than 200 MW installed, and our engineering group builds the software we use ourselves. SurgePV came out of that: a design suite written by people who had to defend a yield number to a client and a lender in the same week. Every proposal we issue carries a shading heatmap with the sky model stated, and on any site with a low-rise neighbour we run the permitted-envelope scenario alongside it.

• Commercial Solar: 10 to 100 kW with module-level shading analysis suitable for technical review.
• Industrial Solar EPC: 100 kW+ turnkey projects with performance guarantees underwritten by the shading model.
• Solar EPC services: turnkey delivery with the shading study attached to the contract.
• Solar Calculator: sizing and savings in 60 seconds.

For the engine itself, see the SurgePV shadow analysis module. For the drawing and calculation side, Heaven Designs’ solar design software resource centre covers the deliverables that sit around a shading study.

Related Solar Software Guides

• Solar Shading Analysis Software: The Global Guide
• Best Solar Design Software in Singapore
• Best Solar Proposal Software in Singapore
• Best Solar Software in Singapore: The Full Stack
• Best Solar Shading Analysis Software in Malaysia
• Best Solar Shading Analysis Software in the Philippines
• Floating Solar Design Software
• Best Solar Design Software: The Global Ranking

Frequently Asked Questions

What is the best solar shading analysis software in Singapore in 2026?

SurgePV ranks first on our 5-point Singapore shading bench with 44 of 50, at about SGD 1,730 per user per year on the 5-User Team plan. It runs 8,760-hour module-level simulation with anisotropic sky transposition stated in the report, and it places adjacent blocks at typed heights fast enough that a six-block HDB precinct is a short job. PVsyst ties it at 44 and is cheaper, at CHF 700 per user per year against US$1,299, so it is the stronger choice on budget as well as wherever a lender or technical adviser names the tool. For facade and BIPV work, Ladybug on Rhino beats both.

How much row spacing does a rooftop array need in Singapore?

Much less than European templates assume. Singapore sits at 1.35N, so solar noon elevation never drops below about 65.2 degrees and one metre of array height casts only 0.46 m of shadow at the worst noon of the year. Protecting a 9 am to 3 pm December window, a 2.28 m module in portrait at 15 degrees tilt needs roughly 2.58 m of pitch, against about 4.55 m at Berlin latitude. Ground coverage ratios of 0.86 to 0.91 are normal here.

Why is adjacent-building shading the main problem in Singapore?

Because vertical density is the defining feature of the built environment and there is almost no detached residential market. Almost every array sits on an HDB block roof, an industrial roof, a car park deck or a facade, and in each case the tallest object nearby usually belongs to somebody else. At the December noon factor of 0.46 m per metre, a 36 m block casts 16.7 m and a 75 m block casts 34.7 m, rising to 43 m and 90 m respectively at 9 am. That decides where the array goes before any other design choice.

What is future-state shading modelling and why does Singapore need it?

It is running the shading study twice, once against the skyline as built and once against the worst legally buildable version of the adjacent parcels. Singapore redevelops fast enough that a low-rise neighbour can be replaced by a tower inside a 25 year PV asset life, and the Urban Redevelopment Authority Master Plan publishes the zoning and building height controls that tell you how tall that tower may be. If you sign a generation guarantee against today’s skyline without pricing the permitted envelope, you have taken an unpriced risk.

Do PV design tools model facade and vertical-surface irradiance properly?

Most do not. They will place a vertical plane and return a number, but they apply a single ground albedo and an isotropic or lightly anisotropic sky, which misses the two terms that dominate a facade in a dense cluster: the restricted sky view factor of a street canyon and inter-reflection from surrounding glass. A Radiance-based toolkit such as Ladybug and Honeybee on Rhino traces those properly. Note also that at 1.35N a vertical plane receives roughly 35 to 45 percent of horizontal irradiance, and east and west elevations outperform north and south.

How is shading analysis different for floating solar on a Singapore reservoir?

It is close to the opposite problem. On open water the horizon is near zero, so there is no adjacent tower and no rooftop plant. Only three terms remain: inter-row self-shading on low-tilt floats, which at 1.35N is very small, perimeter bund and treeline shading on the outer rows only, and mooring-driven tilt and heading variance, which is an incidence angle effect rather than shading. If a floating study returns a large shading loss, someone has applied a rooftop template. The modelling effort belongs on water-cooling gain, soiling and mooring instead.

Is a shading report required by Singapore regulation?

No. There is no statutory requirement. The Energy Market Authority sets the licensing and market framework and SP Group runs the physical connection and metering, and neither mandates a shading study. The pressure is commercial: SolarNova and rooftop tenders are won on the yield assumption, most commercial rooftop work is a 20 year lease or power purchase agreement where the developer carries generation risk, and lenders want shading as an explicit line in a P50, P75 and P90 loss tree.

Does the sky model matter for shading analysis in Singapore?

Yes, and more than most designers assume. The annual diffuse fraction of global horizontal irradiance in Singapore runs above 55 percent under persistent convective cloud, so most energy reaches a module from the sky dome rather than the solar disc. An isotropic model reduces shading loss to a simple sky view factor and prices a blocked horizon identically to a blocked zenith, when the two carry different radiance. Insist on Perez or Hay-Davies and insist that the report names which one was used.