【How to perform shading analysis in PVSyst｜7 steps from 3D scene creation】

Table of Contents

• What PVSyst shading analysis can do

• Information to prepare before shading analysis

• Step 1: Check project conditions and basic layout

• Step 2: Create the site and reference surface in the 3D scene

• Step 3: Place the PV module surface

• Step 4: Enter surrounding obstacles and terrain conditions

• Step 5: Check the sun path and how shadows fall

• Step 6: Reflect near shading losses in the calculation settings

• Step 7: Review the results and use them to improve the design

• Common mistakes and countermeasures in shading analysis

• The importance of on-site measurements to improve shading analysis accuracy

• Summary

What You Can Do with PVSyst Shadow Analysis

PVSyst's shading analysis is a feature that reflects in the simulation the effects of obstacles around a PV system and the shading between module rows. The energy output of a solar power system is affected not only by irradiance and temperature but also by the duration of shading on parts of the photovoltaic modules, the extent of that shading, and the season in which it occurs. In particular, low solar altitude in the morning and evening, long shadows around the winter solstice, shadows from adjacent buildings or trees, and inter-row shading caused by insufficient fore-and-aft spacing of racking rows manifest as differences in annual and monthly energy yield.

PVSyst lets you place module surfaces, rows of racking, buildings, walls, tree-like obstructions, and surrounding shading objects on a 3D scene to check at which times shadows occur relative to the sun’s movement. This enables the effects of nearby shading—which are difficult to assess using only simple azimuth and tilt angles—to be incorporated into power generation simulations. Results that account for shading are useful for comparing design proposals, revising module layouts, adjusting racking pitch, reassessing system capacity, and preparing explanatory materials for power generation forecasts.

What matters in practice is not to treat shading analysis as a task of merely making a slight correction to the energy production. Shadows occur locally, but depending on string configuration and circuit design, the reduction in output can spread beyond the shaded area. Also, there are places where shadows appear only in the morning, places where shadows lengthen only in winter, and places where only the site edges are affected — so the way shading impacts the entire plant is not uniform. Therefore, in PVSyst shading analysis it is important to make the 3D scene as close as possible to the actual site conditions so that the analysis results can be used for design decisions.

On the other hand, creating an overly detailed 3D scene does not necessarily improve accuracy. If you build a complex model while the input values remain inaccurate, the appearance may be detailed but the reliability of the analysis will be low. What matters is identifying the factors that generate shadows and prioritizing the input of elements that most affect power generation. By accurately organizing conditions that are directly linked to actual shadows—such as the heights of adjacent buildings, the spacing between module rows, the height of mounting structures, the slope of the site, and the relative positions of obstacles—the practicality of shadow analysis increases.

Information to Prepare Before Shadow Analysis

Before starting a shading analysis in PVSyst, first organize the project's prerequisites. Creating the 3D scene can be done on-screen, but accurate input requires information about the on-site conditions. At minimum, confirm the site orientation, the area where modules will be installed, the positions and heights of surrounding obstacles, the slope of the ground or roof surfaces, the height of the mounting structure, the front-to-back spacing of module rows, and the shapes of objects that will cast shadows, such as buildings and trees. If you proceed while these are unclear, you'll face more revisions later and it will be harder to explain the simulation results.

In practice, design drawings, layout plans, on-site photographs, survey results, existing terrain data, architectural drawings, and distances and heights measured on site are often combined to create a 3D scene. For rooftop projects, roof orientation, pitch, parapet height, equipment locations, lightning protection, ventilation equipment, and the heights of adjacent buildings have an impact. For ground-mounted projects, site boundaries, graded surfaces, slope faces, surrounding trees, utility poles, fences, substation equipment, maintenance access paths, and adjacent facilities are factors that cause shading. On sloped terrain, the height relationships of the module surface itself and level differences caused by the terrain also cannot be ignored.

When organizing information for shadow analysis, it is not necessary to try to reproduce every object as a complete 3D model. What is important is appropriately representing the outline that blocks sunlight. For example, for buildings that are far away, the height and width that create shadows and the direction as seen from the installation area are more important than fine details such as windows or surface irregularities. For nearby walls or equipment, the important factors are the distance to the module surface, the top-edge height, and the times when shadows fall, rather than detailed shape. Trees change the intensity of their shadows depending on the season and the condition of branches and foliage, but in simulations you should decide—based on the project's purpose—whether to assume a conservative case or to represent them with heights and extents that closely reflect reality.

Also, it is important to decide upfront the purpose of performing shading analysis in PVSyst. Whether you want to grasp annual losses for power generation forecasting, compare design proposals, explain shading risks before construction, or verify causes of reduced power generation in existing facilities, the required level of accuracy and degree of detail in the 3D scene will vary accordingly. While a rough assessment of shading impacts may be sufficient at the proposal stage, more careful input is required in detailed design and profitability studies to avoid underestimating shading losses.

Step 1: Confirm project conditions and basic layout

The first step in shadow analysis is to verify that the project conditions and basic layout are correctly set in PVSyst. Even if you create the 3D scene correctly, if the site, azimuth, tilt angle, system capacity, or module plane conditions are off, the results of the shadow analysis will diverge from reality. In particular, the site information and azimuth settings directly affect the sun-path calculations, and therefore influence the direction and timing of shadows.

First, confirm that the target site's latitude and longitude, elevation, selected meteorological data, and time conditions are appropriate for the project. Because shadows for solar photovoltaic systems are determined by solar altitude and azimuth, if the site is offset the length of winter shadows and the direction of shadows in the morning and evening will change. Even for domestic projects, solar altitude and insolation conditions vary by region. Even if you are provisionally using data from a similar area, at the stage of conducting a full-scale shadow analysis it is desirable to align the conditions with those of the target site.

Next, check the azimuth and tilt angle of the module surface. On flat ground installations this is relatively simple, but on roofs or sloping sites the azimuth and tilt may differ for each installation surface. If the installation is divided into multiple roof surfaces, or there are east-west, north-south orientations, or stepped mounting racks, treating them as a single simple surface will not correctly represent how shadows fall. If necessary, divide the installation surfaces into multiple parts, organize the azimuth and tilt of each surface, and then create the 3D scene.

In the basic layout, you also check the number of module rows, row spacing, racking height, module-plane dimensions, and installation area. When evaluating inter-row shading, the spacing and height relationship between the front and rear rows is extremely important. If the racking pitch is small, the front row’s shadow is more likely to fall on the rear row during winter mornings and evenings. Conversely, widening the racking pitch reduces shading losses but may decrease the capacity that can be installed on the same site. PVSyst’s shading analysis is useful for examining such design trade-offs.

One point to watch here is whether the basic design assumptions have been shared within the company and among stakeholders before performing shadow analysis. If the design engineer, the person in charge of power generation simulation, the sales representative, and the construction manager are each operating under different assumptions, the meaning of the analysis results becomes ambiguous. For example, it often happens in practice that the layout drawing is the latest version but the simulation uses an old row spacing, or that after a site survey the height of an obstacle was revised but not reflected in PVSyst. Checking version control of the input conditions before starting the shadow analysis can reduce rework in later stages.

Step 2: Create the site and reference plane in the 3D scene

Next, create the site and reference planes in the 3D scene of PVSyst. The 3D scene is the task of representing the positional relationships between objects that cast shadows and the module surfaces that receive them. Here, prioritize correctly reproducing the relationships of distance, direction, and height over visual appearance. If the reference plane is misaligned, all modules and obstacles placed on it will be offset, so establishing the initial reference is important.

When entering the site, first confirm the orientation. If the north on the drawing and the orientation in PVSyst do not match, shadow directions can be reversed and the way shadows appear in the morning and evening may not match reality. When referring to layout plans or survey maps, the top of the drawing is not necessarily true north. Check the orientation symbols, coordinate axes, directions of the site boundaries, and the shooting directions of on-site photographs shown on the drawing, and align the orientation of the entire scene.

The reference surface is treated as the base for placing modules, such as a flat ground surface, a roof surface, or a developed/graded surface. On flat ground it can be created as a horizontal plane, but on a roof it should reflect the roof pitch, and on sloping terrain it should reflect the ground slope. When the actual topography is complex, rather than reproducing every undulation in detail, it is practical to represent it by dividing it into the main surfaces that affect shading and module layout. For example, on a developed site with stepped levels, reproducing the height and front‑to‑back relationships of each step makes it easier to examine inter-row shading and slope-face shading.

It is also important to be aware of site boundaries and the areas available for installation within the 3D scene. In PVSyst’s shading analysis, calculations can be performed as long as module surfaces can be placed, but in real projects there are setbacks from boundaries, walkways, maintenance spaces, locations for equipment, and constraints during construction. It is not necessary to fully detail all of these, but understanding them as areas related to shading and as limits on module placement enables a study that is closer to real-world practice.

Common mistakes at this stage are errors in units and scale. When entering dimensions read from drawings, mix-ups between meters and millimeters, reading errors from scaled drawings, and confusion between the horizontal projected dimensions of a roof surface and the dimensions along the slope can occur. After creating the 3D scene, check several representative distances and review whether they match the on-site or drawing dimensions. In particular, distances to obstacles and module row spacing directly affect shadow analysis, so they should be checked early on.

Step 3: Position the photovoltaic module surface

When the reference plane is ready, place the photovoltaic module surfaces. In shadow analysis, because the module surfaces are the objects receiving shadows, placement position, dimensions, tilt angle, azimuth, and height are important. In PVSyst, module surfaces are arranged either as single units or as multiple rows to create a configuration close to the plant layout. If the input here is too coarse, it becomes difficult to correctly assess the effects of inter-row shading and shadows from surrounding obstacles.

For ground-mounted installations, check the orientation of the racking rows, the number of rows, row spacing, the height of the module plane, and front-to-back elevation differences. To evaluate inter-row shading, it is important to know where the front row’s top and bottom edges lie relative to the rear row. Even with the same tilt angle, the way shadows reach changes if racking height or ground slope changes. Especially for south-facing fixed racks, in winter the shadow of the front row can fall on the lower part of the rear row, affecting not only annual losses but also winter energy generation and output in the mornings and evenings.

On roofs, separate the module arrays and arrange them for each roof plane. On single-slope, gable, multi-ridge, or stepped roofs, shading conditions can differ even within the same building. Modules placed near parapets or equipment are more susceptible to shading than other modules, so it is important to position them close to their actual placement. The distance from the roof edge and the clearance from equipment affect not only shading but also constructability and maintainability.

When placing module surfaces, also be mindful of their relationship with the electrical design. In shadow analysis you look at the geometric area and duration of shadows, but actual reductions in power generation are also influenced by the circuit configuration. Even when shadows fall on only some modules, they can affect the output of the circuit to which those modules belong. How comprehensively PVSyst reflects detailed electrical shading effects depends on the configuration settings, but at a minimum you should confirm that areas where shading concentrates do not conflict with the circuit layout.

Also, after placing modules in a 3D scene, check not only the top-down arrangement but also the side and oblique views. Even if the layout appears correct on the plan, heights can be misaligned, modules can be buried below the ground surface, or they can overlap with obstacles. Because vertical misalignment has a large impact on shadow analysis results, it is important not to neglect three-dimensional verification.

Step 4: Enter surrounding obstacles and terrain conditions

After placing the module surface, enter the surrounding obstacles and terrain conditions that cast shadows. This is the part of PVSyst's shading analysis where practical differences most often appear. Surrounding buildings, walls, trees, utility poles, fences, slopes, site equipment, adjacent racking rows, etc., — the objects that cause shading vary by project. Because entering everything with the same level of detail would make the work excessive, prioritize modeling those that have the greatest impact on energy production.

What is particularly important for near shading are objects that are close to the module plane and that block the sun’s path. For example, if there is a tall building to the south, long shadows are likely to occur during times in winter when the sun’s altitude is low. Obstacles to the east or west affect power generation in the morning or evening. Obstacles to the north usually have little effect, but depending on the terrain and the installation azimuth they can sometimes not be ignored. By combining azimuth and distance, you can determine which obstacles are important for analysis.

Artificial structures such as buildings and walls are objects that are easy to represent as rectangular prisms or planes. Even if the actual building shape is complex, simplifying and inputting the outline that casts shadows can often allow sufficiently practical assessments. What is important is the extent of shading as seen from the module and the height of the top edge. In rooftop projects, parapets, roof penthouses, equipment foundations, and piping spaces can create localized shadows, so elements close to the modules should be entered carefully.

Trees are challenging objects to handle. Shading conditions change depending on height, branch spread, leaf density, seasonal variation, and future growth. In simulations, trees are often modeled as simple obstacles, but how conservative you should be depends on the purpose of the project. If the aim at the proposal stage is to show risks, use a slightly conservative approach; if the aim is to understand the actual state of existing equipment, input values close to current conditions. Recording the rationale for your judgments makes them easier to explain.

Terrain conditions also affect shadow analysis. On sloped terrain, differences in ground elevation change inter-row shading, and cut slopes or surrounding slopes can also obstruct sunlight. Because the pre-development terrain, the planned ground after development, and the actual ground after construction may differ, it is necessary to make clear which stage of terrain is being used for the analysis. If the analysis is to be used for predicting post-construction power generation, the basic approach is to align it with the planned ground or the as-built ground conditions.

After entering obstacles, check that the distance to the module, height, and azimuth match the on-site information. In shadow analysis, position shifts or height errors of just a few meters can affect the presence or absence of shadows at certain times of day. This is especially true for obstacles close to the module, where slight dimensional differences can have a major impact. After inputting them, rotate the 3D scene and make sure the arrangement does not look unnatural when viewed from directions where the sun is low.

Step 5: Confirm the sun's path and how shadows fall

Once module surfaces and obstacles are placed in the 3D scene, check the sun path and how shadows fall. Here you visually identify in which seasons and at what times of day during the year shading occurs. In PVSyst you can observe the movement of shadows according to the sun’s position, so you can understand the mechanism of shading before simply looking at the annual loss rate.

The first thing to check is winter shadows. During periods when the sun’s elevation is low, shadows cast by obstacles extend farther and inter-row shading is more likely to occur. Compared with summer, when power generation is higher, solar irradiance in winter tends to be lower, but if shadows persist for long periods they will affect monthly energy output. Check the position of shadows in winter in the morning, around noon, and in the evening, and see which parts of the module surface are shaded.

Next, check the morning and evening shadows. When the solar altitude is low at those times, shadows from obstacles and surrounding buildings in the east–west direction extend considerably. Their impact on annual energy production can be smaller than shadows around noon, but because they affect the ramp-up of the generation curve and evening output, they are important for projects that involve energy storage systems, self-consumption, or time-of-day generation assessments. By understanding not only the simple annual energy production but also which time periods see drops in output, you can provide a more practical explanation.

Also, verify whether the shading falls uniformly across the entire module or is localized to certain areas. Even partial shading of a photovoltaic module can affect its output. In the 3D scene in PVSyst, while checking the shape and movement of shadows, inspect whether shadows are concentrated on specific module rows, edges, lower tiers, or around rooftop equipment. If shading is locally concentrated, fine‑tuning the layout or reviewing the circuit design may be necessary.

At this stage, you need to pay attention not only when shadows are larger than expected but also when they are smaller than expected. If on-site photos appear to show large shadows but PVSyst shows almost no shading, the orientation settings, obstacle heights, date/time conditions, or the position of the module plane may be incorrect. Conversely, if the scene shows large shadows but that does not match on-site impressions, you should review the input values. Visual verification is an important step for detecting input errors before the numerical results.

When checking the sun's path, be aware of seasonal differences rather than looking only at representative days. Around the summer solstice, in spring and autumn, and around the winter solstice, the sun's elevation and trajectory change significantly. Conditions that cause shading only once a year have a different impact on annual power generation than conditions that produce shading every day for several months. If the purpose of shadow analysis is design improvement, it is important to identify the periods and times of day when shading occurs and to find locations where improvements are likely to be effective.

Step 6: Incorporate proximity shading loss into calculation conditions

Once you have checked how the shadows fall, incorporate the near-shading losses into the simulation calculations. Simply creating a 3D scene may not have the shadowing effects reflected in the energy yield results. In PVSyst, by setting the shadow calculation conditions and incorporating them into the simulation, you can reflect shading losses in the annual energy production and loss diagrams. In this step, be mindful that the verification of the 3D scene and the setting of the calculation conditions are linked.

Proximity shading losses can be evaluated in terms of geometric shading and electrical impact. The geometric assessment deals with how much shading falls on the module surface. The electrical impact relates to how shading causes output reduction across the entire power-generating circuit. In practice, how far to use detailed settings depends on the project, but to avoid underestimating shading effects it is important to at least reflect the conditions that cause proximity shading in the simulation.

When applying, confirm that the target module surfaces correspond to their placement in the 3D scene. If there are multiple installation surfaces, it can become ambiguous which shading conditions apply to which surface. If conditions differ for each roof surface, each racking block, or each orientation, align the surface divisions in the simulation with the surface divisions in the 3D scene. If these are misaligned, even a visually correct 3D scene will not reflect the intended shading in the calculation results.

Also, after reflecting shadow losses, we recommend comparing with the no-shadow case. Comparing the no-shadow case, a basic-shadow case, and a detailed-shadow case makes it easier to understand how much the energy yield changes due to the shadow analysis. If the difference in energy yield is larger than expected, check the obstacles you entered and the row spacing. If the difference in energy yield is smaller than expected, also check whether the shadow conditions are included in the calculation and whether the 3D scene matches the simulation conditions.

Rather than looking only at shadow-loss figures, also check when those losses occur. Even if the annual loss is only a few percent, it can be concentrated in particular months or times of day. For example, in cases where shadows are concentrated on winter mornings, the annual figure may seem small, but compared with actual winter generation it can appear as a large discrepancy. When using this information for post-operation performance evaluations or explanatory materials, monthly and time-of-day breakdowns are also important.

Step 7: Review the results and use them to inform design improvements

Finally, review the simulation results incorporating the shading analysis and use them to guide design improvements. PVSyst’s shading analysis is not just about producing results and stopping there. By considering where shading losses occur, whether those losses can be reduced through design changes, whether the balance between energy production and installed capacity is appropriate, and how to explain these issues to stakeholders, the practical value is increased.

First, check the annual energy generation, monthly generation, loss diagram, and near-field shading loss items. If shading losses are significant, review which obstacles are the primary cause in the 3D scene. If surrounding buildings or trees are responsible, consider measures such as shifting the layout, reducing modules in shaded areas, optimizing the circuit configuration, or designating heavily shaded areas as maintenance space. If inter-row shading is the cause, options include reviewing the racking pitch, tilt angle, racking height, and installed capacity.

In design improvements, it is important not to aim solely at reducing shading losses to zero. If row spacing is increased too much to avoid shading, the number of modules that can be installed on the site may decrease and total power generation may fall. Conversely, maximizing installed capacity can increase shading losses and potentially reduce power generation efficiency and maintainability. In practice, decisions are made by comprehensively considering annual energy production, capacity utilization, constructability, maintainability, site constraints, and potential future changes in obstructions.

When explaining results to stakeholders, simply saying "shadow loss is X percent" is insufficient. Being able to explain which obstacle causes the shading, at what times of year, and over which area the shadow will fall creates confidence in design decisions. Especially when explaining to clients or internal approvers, combining a visual review of the 3D scene with the quantitative impact on energy production makes the findings easier to understand. Shadow analysis also provides a common basis for discussion among sales, design, construction, and operations stakeholders, not just technical personnel.

Also, when comparing design proposals, prepare multiple patterns instead of judging based on a single result. For example, comparing a standard layout, a layout with increased row spacing, a layout with reduced modules near obstacles, and a layout with a changed tilt angle makes it easier to see the relationship between shading losses and total energy production. As for using PVSyst, it is important to manage conditions by separating cases and organizing them so that changes are clear. If you carefully save condition names and notes, it will be easier to assess the results later.

Common Mistakes and Countermeasures in Shadow Analysis

One common mistake in PVSyst shadow analysis is incorrect orientation settings. Even if you think you have correctly placed modules and obstacles in the 3D scene, if the north direction is off the shadows will change. Especially when entering data manually while looking at drawings, you may assume that the top of the drawing is north. As a countermeasure, cross-check the orientation symbol, coordinate axes, on-site photos, and survey information, and always verify the direction within the 3D scene.

Another common issue is the lack of height information. Even if the planar positions of obstacles are known, if heights are entered as rough estimates the shadow lengths can change significantly. Building height, parapet height, tree height, mounting structure height, and differences in ground elevation directly affect shadow analysis. When heights are unknown, combine on-site measurements, drawing checks, and estimates from photographs. However, if estimated values are used, it is important to record which values were assumed.

Underestimation of inter-row shading is also common. Even when racking with the same pitch is aligned on flat ground, during periods in winter when the solar altitude is low, shadows from the front row can fall on the rear row. On sloped terrain, the pattern of shading changes further depending on the relative heights of the front and rear rows. When checking inter-row shading, verify not only winter mornings and evenings but also the impact on annual energy production and monthly losses. Comparing cases with different racking pitches makes design decisions easier.

Over-simplifying obstacles can also be problematic. If an obstacle is distant, simplifying it may have little impact, but if you input an obstacle near the module roughly, the presence or absence of a shadow can change. In particular, rooftop equipment and parapets create localized shadows at close range, so set their positions and heights carefully. Conversely, you should avoid over-detailing to the point that the workload increases and important dimension checks are neglected. In shadow analysis, it is important to prioritize and improve accuracy for elements that affect power generation.

Care must be taken when interpreting the results. A small annual value for shading losses does not necessarily mean there is no practical problem. If shadows are concentrated on specific strings or during specific times of day, they can affect the generation curve during operation and the decisions made during inspections. Conversely, even if the annual value is somewhat large, a design that increases installed capacity can still be advantageous for total generation. The results of shading analysis should be evaluated not on their own merits but in light of the project's objectives and constraints.

The Importance of On-Site Measurements to Improve the Accuracy of Shadow Analysis

To bring PVSyst’s shading analysis close to an accuracy usable in practice, the quality of on-site measurements is crucial. A 3D scene can be created on-screen, but the basis for the positions and heights you input comes from on-site information. Especially for projects with many surrounding obstacles, on sloping ground, on rooftops, or where existing structures are complex, judging from drawings alone can differ from actual conditions. Accurately understanding the on-site situation increases the reliability of the shading analysis.

On site, organize and record the planned module installation area, the positions of obstacles, the heights of obstacles, the site elevation differences, the roof pitch, and the photo locations and directions. Rather than just taking photos, also note from which location and in which direction each photo was taken, the approximate distance to the subject, and the height above ground level; doing so makes it easier to input the information into PVSyst later. Because it is difficult to judge heights and distances from photos alone, combining them with positioning data and simple dimensional records is effective.

Also, in on-site measurements, not only the objects that cast shadows but also the reference positions of the module surfaces that receive shadows are important. Recording the four corners of the planned installation area, the reference lines of the racking rows, the edges of the roof surface, and the locations of steps and slopes makes it easier to establish references for a 3D scene. In particular, when reconciling multiple drawings and photos later, the positional relationships become ambiguous without common reference points. Clarifying reference points on site is useful not only for shadow analysis but also for design, construction, and inspection.

In practice, there can be a gap between on-site surveys and simulation work. Therefore, it is important to preserve information obtained on site as data rather than rely on the person in charge's memory. By organizing photographs, survey points, notes, annotations on drawings, and records of obstacle heights, it becomes easier for another person to share the assumptions even when performing shading analysis in PVSyst. Conversely, if information exists only in the person in charge's memory, rework will be required when conditions need to be confirmed or reanalyzed later.

What is useful here is a positioning environment that can record on-site location information with high precision. In shadow analysis, the positional relationships between obstacles and module installation areas are important, so the ability to later verify the coordinates of points and the locations of photos acquired on site is a major advantage. In particular, for candidate site surveys for solar power plants, rooftop condition checks, understanding elevation differences of developed land, and recording surrounding obstacles, whether the information obtained on site can be directly fed into design considerations greatly affects work efficiency.

Summary

To perform shading analysis in PVSyst, it is important to understand the workflow: create a 3D scene, enter the module surfaces, surrounding obstacles, and terrain conditions, verify the sun path and shadow formation, and then incorporate the near-shading losses into the simulation. Shading analysis is not merely an operational procedure; it requires careful consideration of how to model site conditions and how to link that modeling to energy-yield forecasts and design decisions.

The basic workflow consists of seven steps: reviewing project conditions and the layout; creating the site and reference plane in the 3D scene; placing the module surfaces; entering obstacles and terrain; checking the movement of shadows using the sun path; reflecting near shading losses in the calculations; and using the results to inform design improvements. By following this flow, PVSyst's shading analysis can be used not only for energy yield prediction but also for layout studies, risk explanations, internal sharing, and pre-construction checks.

What’s important in shadow analysis is not just creating a 3D scene that looks detailed. It’s about correctly capturing orientation, distance, height, terrain, and the positional relationships of obstacles, and prioritizing the input of factors that affect power generation. Rather than judging solely by the annual value of shading loss, checking which seasons, which times of day, and which areas are affected by shadows enables a more practical evaluation. Comparing with a no-shadow case and comparing multiple design proposals are also useful for design decisions.

On the other hand, the analysis accuracy in PVSyst is heavily dependent on the accuracy of the information collected on site. If the heights and positions of surrounding obstacles, the planned installation area, ground elevation differences, and roof surface conditions remain unclear, the reliability of the simulation results will decrease. Recording information during the field survey in a form that can be easily reflected later in a 3D scene is the quickest way to achieve successful shading analysis.

For on-site surveys and pre-design checks of solar power plants, using iPhone-mounted high-precision GNSS positioning devices like LRTK makes it easier to record with high accuracy the planned installation area and the locations of surrounding obstacles. If you can organize the assumptions for creating 3D scenes and performing shading analysis in PVSyst based on location data and photo records obtained on site, it will not only improve the accuracy of power generation simulations but also make it easier to explain to stakeholders, compare results when design changes occur, and verify conditions before and after construction. To make practical use of PVSyst’s shading analysis in real projects, it is important to consider the software settings and the quality of on-site data together.