How to Read the PVSyst Manual｜7 Key Points Beginners Should Know

Table of Contents

• Basics to understand before reading the PVSyst manual

• Point 1: First, grasp the overall purpose before reading.

• Point 2: Follow the project creation workflow step by step

• Point 3: Verify the meaning of meteorological data and location settings

• Point 4: Check the solar panels and power conditioner settings

• Point 5: Understand how to read loss settings

• Point 6: Understand how to interpret simulation results

• Point 7: Organize the items to be checked in report output

• How to Read the PVSyst Manual for Practical Use

• Summary

Basics to Understand Before Reading the PVSyst Manual

What tends to trip up people reading the PVSyst manual for the first time is not the screen field names or the technical terms themselves, but the fact that it’s hard to see what each field is meant to be set for. PVSyst is often used as a standard analysis tool for simulating the power output of photovoltaic installations, and it comprehensively handles power generation, losses, system configuration, shading conditions, and meteorological conditions. Consequently, the manual lists many configuration items, but if beginners try to read all of them at the same depth, they can actually lose sight of the overall picture.

When reading the PVSyst manual, it is more important to understand the workflow—from creating a project to reviewing the analysis results—as a single process than to try to memorize the meaning of every detailed numerical input from the start. Simulating a solar power system is not something that ends simply by entering the panel capacity. The estimated final energy production is the result of accumulated factors such as the site’s solar irradiance, temperature, azimuth, tilt angle, the electrical configuration of the equipment, losses due to wiring and temperature, and the effects of shading. In other words, the purpose of reading the manual is not merely to learn which buttons to press but to understand how each setting influences the results.

For beginners, it's easier to understand if you first divide the entire manual into "operation instructions" and "support for design decisions." "Operation instructions" refers to procedures such as creating a project, selecting a site, registering equipment, running simulations, and generating reports. On the other hand, "support for design decisions" covers practical judgments such as which meteorological data to use, how to set loss rates, and how to compare differences in azimuth and tilt angle. If you confuse the two, even after reading the manual you won't be able to tell where the required settings end and the items for consideration begin.

An important point when reading the PVSyst manual is not to try to create a perfect model at the outset. Beginners should first create a simple project and prioritize experiencing the workflow until the energy output is produced. After that, by gradually digging into each item—weather data, modules, inverters, losses, shading, and reports—the manual’s explanations will more easily connect to the actual screens and results.

In this article, we organize and explain the seven points that people reading the PVSyst manual for the first time should grasp, arranged in the order in which professionals are most likely to get confused.

Point 1: First grasp the overall purpose before reading

The first thing to grasp when reading the PVSyst manual is its purpose: what PVSyst calculates and what it is meant to verify. In solar power system design, you consider not only system capacity and the number of panels, but also annual energy production, monthly generation, loss factors, the appropriateness of equipment configuration, the impact of shading, and generation efficiency. PVSyst quantifies these items and is software used to compare design proposals and to explain expected energy production.

A common mistake beginners make when reading a manual is jumping straight into individual input screens and proceeding without understanding the overall calculation structure. For example, the screen for selecting the panel model, the screen for selecting the power conditioner, and the screen for entering loss rates each appear independent. In reality, however, all of these settings feed into the final power generation simulation. When reading the manual, it is important to view each screen not as a separate operation but as a component that contributes to the overall power generation.

The basic workflow of PVSyst is to decide the installation site, select meteorological data, combine solar panels and power conditioners, enter installation conditions, take losses and shading into account, and review the simulation results. Understanding this flow beforehand makes it easier to determine which step a given explanation in the manual refers to. Conversely, reading without an overall picture can leave you unsure of the relative importance of each item and cause you to spend too much time on detailed settings.

Also, the PVSyst manual uses many technical terms. Terms such as solar irradiance, tilted‑plane irradiance, system losses, temperature losses, mismatch losses, clipping, and performance ratio may be unfamiliar to beginners. You do not need to memorize all of them at once. First, by broadly dividing the factors that affect energy production into "natural conditions", "installation conditions", "equipment conditions", "loss conditions", and "result verification", you can reduce the burden of understanding.

The purpose of reading the manual is not just to run the software. It is important to be able to explain why a result occurs under the conditions you set. In practice, simulation results are sometimes used for internal review, client presentations, design comparisons, and profitability assessments. In those cases, simply saying "calculated with PVSyst" is not enough. You must be able to explain which conditions were entered, which losses were considered, and under what assumptions the projected energy production was estimated.

Therefore, when first approaching the PVSyst manual, it is important not just to follow the steps but to be aware of how each setting relates to energy production. As you read each chapter of the manual, classify items as "related to location," "related to equipment," "related to losses," or "related to how results are viewed" — doing so makes it easier for beginners to organize the overall picture.

Point 2: Follow the project creation process step by step

What I want to check next in the PVSyst manual is the basic workflow for creating a project. For beginners, creating the first project is the most important learning step, because many of PVSyst's functions operate based on the project. If a project is not created correctly, the site settings, equipment selection, simulation conditions, and report outputs will all become unstable.

When creating a project, first organize the basic conditions of the solar power generation system to be analyzed. The main information includes the installation location, system size, installation method, azimuth, tilt angle, modules to be used, power conditioners to be used, and connection configuration. When consulting the manual, proceed while confirming which information is entered at each stage; this makes the meaning of screen transitions easier to understand. Rather than jumping straight into detailed settings, it is better to first create the project's container and then place the conditions into it in order.

What beginners often find confusing is that similarly appearing settings show up in multiple places. For example, information about the installation site is relevant in several contexts, such as site settings, meteorological data, system design, and report output. Likewise, information about equipment capacity is connected to the number of modules, string configuration, inverter capacity, and considerations of oversizing. Even if the manual explains each as a separate screen, in practice they need to be consistent as a single design condition.

What’s important at the project creation stage is not to rush into deciding the input values. If you try to reproduce the exact same conditions as a real project from the outset, you tend to get stuck on minor details. For beginners, it’s effective to first build a simple model under standard conditions and proceed until you obtain simulation results. From there, change the conditions one at a time and observe how the results vary; this makes the manual’s explanations easier to grasp intuitively.

The manual may introduce concepts such as projects and variants. A variant is easiest to understand if you think of it as a unit for comparing different design options based on the same installation location and basic conditions. For example, when you change the tilt angle, change module capacity, change inverter configuration, or change loss settings on the same site, it becomes easier to compare multiple options. Beginners should keep in mind that creating a single project is not the end, and use it as a container for comparing different conditions.

Also, file management is important when creating projects. As the number of cases with similar names or data for different conditions increases, it can become unclear which simulation is the latest. When reading the manual, checking the relationships between saving, copying, variant management, and report output makes later review easier. In practical work, initial proposals, revisions, submissions, and comparison variants tend to multiply, so it is important to give clear project and condition names.

The project creation section of the PVSyst manual is not merely a description of initial operations, but an important part that lays the foundation for the entire analysis. By understanding this section carefully, subsequent meteorological data settings, equipment configuration, loss settings, and result verification will proceed smoothly.

Point 3: Confirm the meaning of meteorological data and location settings

When reading the PVSyst manual, beginners should pay special attention to the weather data and site settings. The power production of a solar PV system is strongly influenced by the irradiance and the ambient temperature at the installation site. No matter how high-performance the modules are, if the assumed irradiance and temperature conditions do not match reality, the reliability of the simulation results will decline. Therefore, the manual emphasizes the need to carefully verify the selection of weather data and the handling of site information.

Meteorological data are the fundamental information for estimating annual power generation. Data such as solar irradiance, ambient temperature, and wind speed are used in the analysis. Beginners tend to treat meteorological data as mere background information, but in reality they are important input conditions that directly determine simulation results. When reading the PVSyst manual, you need to check which data are being used, how close the site information is to the location of the meteorological data, and what the period and nature of the data are.

The latitude, longitude, elevation, time zone, and so on of the installation site are also important. These relate to calculations of the sun’s position and the handling of solar radiation conditions. In particular, if you proceed with an analysis after selecting a location only roughly, the actual project site and the conditions in the meteorological data may diverge. When consulting the manual, check what each item in the location settings is used for and be mindful of how accurately you should enter them in real projects.

There are also several types of meteorological data. Depending on which information you choose to use—standard meteorological data, externally imported data, data from nearby locations, etc.—the results may vary. Beginners tend to assume that it won’t make much difference which data they select, but if the assumptions about solar radiation change, the annual energy output will change as well. In the relevant sections of the manual, it is important to read while considering not only how to select the data but also why you are choosing that data.

When examining meteorological data, pay attention to monthly trends. In addition to annual totals, check whether regional characteristics are reflected in the results—differences between summer and winter, the effects of the rainy season and snow-prone areas, and reductions in generation efficiency during high-temperature periods. When using PVSyst results in practice, you may need to explain the plausibility of monthly generation figures rather than showing only annual generation. For that reason, when reading manuals on how to handle meteorological data, it is helpful to adopt a perspective that looks at monthly variations as well as annual values.

Site settings and meteorological data affect all downstream processes. No matter how finely you adjust equipment configuration or loss settings, if the initial meteorological conditions are inappropriate, they will still affect the overall results. Beginners tend to want to rush through the meteorological data setup, but the PVSyst manual stresses that it is important to check this part carefully.

Point 4: Check the solar panels and power conditioner settings

One of the items beginners must always check in the PVSyst manual is the configuration of the photovoltaic panels and the power conditioner. Here you determine the electrical configuration of the power generation system. It involves module output, voltage, current, temperature characteristics, the power conditioner's capacity, input voltage range, MPPT handling, string configuration, and so on. These settings affect not only energy production but also the validity of the design.

When beginners read the manual, it is easier if they first understand the module settings and the inverter settings separately, and then look at how the two are combined. In the module settings, factors such as the rated output of the selected panel and the temperature coefficient affect the power generation calculations. Panels generate DC power when they receive solar radiation, but their output tends to decrease as temperature rises. Therefore, you should not judge performance by panel capacity alone.

Meanwhile, in the power conditioner settings, you verify the conditions for converting DC power to AC power, the allowable input voltage range, the capacity ratio, and so on. In photovoltaic systems, the voltage and current are determined by the number of modules connected in series and in parallel. If these fall outside the power conditioner's specification range, design issues may arise. In the relevant section of the PVSyst manual, it is important not only to know how to select equipment, but also to read and understand the meaning of any warnings and verification items that appear after selection.

One thing beginners should pay particular attention to is the relationship between the system capacity and the inverter capacity. In solar power generation, the panel capacity and the power conditioner (inverter) capacity are not necessarily exactly the same. Depending on the design, a certain amount of oversizing may be assumed. In such cases, while there will be times when generation increases, output limiting and clipping can occur. When reading the manual, check which result items reflect the capacity ratio and the display of limits.

String configuration is also an area where beginners often stumble. Increasing the number of modules in series raises the voltage, and increasing the number in parallel raises the current. Electrical behavior also changes with temperature conditions — for example, open-circuit voltage is higher at low temperatures, while operating voltage drops at high temperatures. PVSyst has a function to check whether these conditions are within the design range, but when reading the manual it is important to understand why that check is necessary.

Care must also be taken when handling the equipment database. Even if you use the registered equipment information as-is, you must confirm that the model, output, and specifications match the equipment that will actually be used. Mistakenly selecting a similarly named model or a product with a different capacity can cause simulation results to diverge from the actual design. In the manual, verify the procedures for equipment selection and data editing, and in real projects it is important to cross-check against the specification sheets.

The equipment-configuration section of the PVSyst manual can feel difficult for beginners, but it is an important area at the heart of generation simulations. First, understand the flow that "modules generate power, power conditioners convert it, and their combination affects the generated energy and losses," and then check the detailed items step by step according to the actual project.

Point 5: Understand how to read loss settings

In the PVSyst manual, the loss settings are what beginners should read particularly carefully. In solar PV simulations, the energy production calculated under ideal irradiance conditions does not directly become the final output. Temperature, wiring, soiling, mismatch, equipment conversion losses, shading, degradation, and output limitations — among other factors — reduce the energy production. In PVSyst, these losses are configured individually and reflected in the final energy output.

One reason beginners often get confused when configuring loss settings is not only that there are many items, but also that it is difficult to judge how significant each loss is. For example, temperature loss relates to output reduction caused by an increase in module temperature. Wiring loss relates to power losses in cables on the DC side and AC side. Mismatch loss is the loss that occurs due to individual variances and differing conditions between modules. Soiling loss assumes effects such as dust on the panel surface, pollen, bird damage, and residual snow after snowfall.

When reading the PVSyst manual, it is important not to treat each loss item merely as an input field, but to connect it to the loss it represents on-site. For example, the way you consider soiling may differ between a ground-mounted project with a lot of dust nearby and a pitched roof project where rain is likely to provide a cleaning effect. Also, in high-temperature regions, temperature losses can have a greater impact. For layouts that require long wiring, checking wiring losses becomes more important.

What you should avoid in loss settings is entering numbers without justification. Beginners sometimes simply reuse initial values or figures from past projects. However, because loss rates vary with project conditions, they must be set taking into account the installation environment, equipment configuration, maintenance plans, cable length, regional characteristics, and so on. In the manual, check the meaning of each item and how to enter it, and in practice it is important to verify the values’ validity by comparing them against design conditions and in-house standards.

Also, even if each loss appears small, when they accumulate they can have a significant impact on annual energy production. Temperature losses, conversion losses, wiring losses, mismatch losses, soiling losses, and other combined effects cause the final energy production to be lower than the ideal value. In PVSyst results, you can check the breakdown of losses, allowing you to identify which factors are having the greatest impact on reduced energy production. When consulting the manual, check not only the settings screens but also how losses are displayed on the results screens to deepen your understanding.

Shading losses are also important. Shadows from nearby buildings, trees, rows of racking, terrain, rooftop obstructions, and so on affect energy generation. The way shading is handled varies in difficulty depending on the project, but beginners should first understand that results differ between cases that do and do not account for shading. The shading-settings section of manuals may explain three-dimensional shading analysis and the treatment of near-field shading, but at first it is important to grasp the basic point that "shading affects annual energy yield and time-of-day output."

Loss settings are one of the areas in PVSyst where professional judgment strongly comes into play. Rather than just reading the manual to learn how to operate it, you should aim to be able to explain why you use particular values and how they affect the results.

Point 6: Understand how to interpret simulation results

In the PVSyst manual, what beginners must ultimately understand is how to interpret the simulation results. After completing the inputs and running the simulation, information such as annual energy production, monthly energy production, a breakdown of losses, the performance ratio, output limitations, and the energy flow is displayed. The important point is not to take those numbers at face value, but to verify their plausibility by comparing them with the input conditions.

Beginners tend to focus first on annual energy production. Of course, annual energy production is an important indicator. Because it directly ties into the system's expected output, financial analysis, and project feasibility assessment, it is one of the figures you should check first. However, annual energy production alone does not allow you to judge whether the contents of a simulation are reasonable. You need to check it together with monthly generation trends, the breakdown of losses, the level of the performance ratio, and effects such as shading and temperature.

By looking at monthly power generation, you can see seasonal generation trends. In general, monthly output varies with solar irradiance, temperature, weather, snowfall, installation angle, and other factors. For example, summer has longer sunlight hours but suffers efficiency losses from high temperatures, while winter may be advantageous temperature-wise but can be affected by reduced sunlight hours and snow cover. When reading the manual, be sure to check where the monthly results are displayed and which metrics you should be reviewing.

Loss diagrams and the energy flow are extremely useful for understanding PVSyst results. You can track how the incident solar energy decreases at each stage and ultimately becomes the final AC output. Beginners may initially find the many items in the loss diagram overwhelming. However, once you can read them, it becomes much easier to identify why the energy production is lower than expected and to spot areas that might be improved by design changes.

The performance ratio is also an important metric. The performance ratio is used as a guideline to see how efficiently a system is generating power compared to ideal conditions. However, it is risky to judge the quality of a system solely by the performance ratio. Because it varies with regional solar irradiation conditions, temperature, loss settings, equipment configuration, shading conditions, and so on, you need to align the assumptions when comparing with other projects. In the PVSyst manual, check the meaning of the performance ratio and where the results are displayed, and it is important not to rely excessively on a single indicator.

Also, when reviewing results, pay attention to warnings and error messages. Caution messages can appear before or after a simulation if the equipment configuration is inappropriate, if there are problems with the voltage range, or if there are contradictions in the input conditions. Beginners may feel reassured simply because results have been produced and overlook warnings. However, using results as-is while warnings remain can lead to missing design problems. In the manual’s result-checking section, be sure to read not only the numerical values but also the meaning of any warnings and checklist items.

Simulation results are material for evaluating a design proposal. Higher energy production does not necessarily mean a better design; it is also necessary to consider the balance with equipment configuration, constructability, maintainability, safety, cost, and installation conditions. When reading the PVSyst manual, it is important to regard the way you interpret the results not as an exercise in "looking at numbers" but as an exercise in "verifying design conditions."

Point 7: Organize the items to check in the report output

The final thing to grasp in the PVSyst manual is how to interpret the report output. Simulation results are not only checked on the screen but are also exported as reports, which can be used for internal sharing, customer explanations, design comparisons, and study materials. Therefore, beginners need to understand what is included in the report and what they should check.

The report consolidates project information, the installation site, meteorological data, system configuration, information on modules and power conditioners, power generation, breakdown of losses, monthly results, key indicators, and so on. These are important pieces of information for explaining the assumptions and results of the simulation to third parties. When consulting the manual, it is important not only to check how to operate the report output but also to confirm what each of the output items means.

The first thing a beginner should check in a report is the consistency of the assumptions. Verify that the installation location is correct, that the meteorological data are as intended, and that the system capacity, module model, and power conditioner model are not mistaken. Before looking at the power generation figures, you must confirm that the assumptions are correct; otherwise you cannot judge the reliability of the results.

Next, what you should check are the annual generation and the monthly generation. The annual value indicates the overall estimate, and the monthly values show seasonal trends. It is important to verify that the monthly results are not largely inconsistent with the regional weather conditions or installation conditions. For example, in projects with significant shading, losses may increase during certain seasons or times of day. In regions where snowfall is expected, winter generation may decrease. When reviewing the report, pay attention not only to the totals but also to the monthly variations.

The breakdown of losses is also an important item to check. In the PVSyst report, you can see at which stages and to what extent losses occur. By checking whether temperature loss, wiring loss, inverter loss, or shading effects are large, you can consider directions for design improvement. Beginners should not view losses merely as negative factors, but read them as information for identifying opportunities for improvement.

In reports, accountability for the simulation conditions is also important. In practice, there are situations where you need to explain why you used particular meteorological data, why you set a given loss rate, and why you chose a specific equipment configuration. While reading the manual, identify which items appear in the report and which do not, so that you can more easily prepare supplementary materials as needed. Especially for internal reviews and client submissions, the PVSyst report alone may not provide sufficient explanation. In such cases, it is important to separately organize the assumptions.

In addition, when comparing multiple report scenarios you need to make the differences in conditions clear. If it is ambiguous whether a scenario only changes the tilt angle, changes the equipment configuration, or also alters the loss settings, the meaning of the comparison results becomes difficult to interpret. When reading the PVSyst manual, it is useful for practical work to understand not only the report output but also the concepts of project management and variant management for comparisons.

A report is the final deliverable that communicates simulation results to external parties. Beginners should aim not to be satisfied just with producing outputs, but to be able to explain the assumptions, results, losses, and caveats.

How to Read the PVSyst Manual for Practical Use

To make practical use of the PVSyst manual, it's important not to read it once and be done, but to use it by consulting the necessary sections for each project. For beginners, attempting to read the manual from start to finish can be overwhelming because of the volume of information and may not readily translate into practical work. Therefore, the recommended approach is to read it in line with the actual workflow.

First, in the initial assessment phase of a project, focus on reviewing project creation, site settings, meteorological data, and the overall equipment configuration. At this stage, it is more important to grasp a rough estimate of power generation than to get bogged down in detailed loss settings or detailed shading analysis. When comparing multiple installation conditions as initial proposals, organize projects and variants so that the differences between conditions are clear.

Next, at the stage when the design proposal is taking shape, verify in detail the modules, power conditioners, string configurations, wiring losses, temperature conditions, shading conditions, etc. At this stage, the explanations of equipment settings and loss settings in the manuals are useful. Rather than entering values without understanding the meaning of the input, it is important to configure them while cross-checking with the design drawings, equipment specifications, site conditions, and construction conditions.

Furthermore, at the stage of preparing submission materials or internal briefings, knowing how to interpret result displays and report outputs becomes important. Organize the annual energy production, monthly energy production, breakdown of losses, performance ratio, etc., and be able to explain why those results occurred. What is important here is not to treat PVSyst’s results as absolute answers, but as simulation results based on the assumptions you set. Because results change if the assumptions change, clearly stating the conditions is indispensable.

When beginners use the PVSyst manual, it's effective to create a personal checklist. For example, each time check whether the site settings have been confirmed, whether the meteorological data are the intended ones, whether the equipment model types are correct, whether the string configuration shows any warnings, whether there is justification for the loss rates, whether shading conditions have been considered, and whether there are any errors in the report's assumptions. Doing so helps reduce operational mistakes and configuration oversights.

Also, because PVSyst is multifunctional, you don't need to master all of its features from the start. Beginners should first become able to reliably perform basic power generation simulations, and then proceed to detailed shading analysis, complex system configurations, battery storage, self-consumption, and special installation conditions. The manual is the same: realistically, begin by focusing on the sections covering basic operation and result verification, and consult the detailed functions as needed.

The value of the PVSyst manual lies in providing a standard you can return to when you are unsure. In practice, conditions differ from project to project, and the same settings used previously are not always appropriate. For that reason, it is important to use the manual not merely as an operating guide, but as a document for verifying the basis of your decisions.

Summary

For beginners reading the PVSyst manual, the key point is not to memorize detailed operations but to understand the flow of the energy production simulation and how each setting affects the results. First, grasp the overall purpose, review the project creation workflow, and understand the meaning of the meteorological data and location settings. Then, deepening your understanding in the order of the solar panel and inverter combinations, loss settings, simulation results, and report output will make it easier to apply the manual’s content to practical work.

For beginners, PVSyst has many items and may feel difficult at first. However, you don’t need to understand all of its features at once. Start by creating a basic project and experience the workflow until you see the energy production results. After that, gradually expand your understanding by changing the weather conditions, modifying the equipment configuration, reviewing the loss settings, and comparing reports; this will make it easier to naturally interpret the contents of the manual.

In practice, what matters is not using PVSyst results as-is, but being able to explain the relationship between the input conditions and the results. Rather than judging solely by whether the generation is high or low, it is necessary to check which meteorological data were used, which equipment was selected, which losses were taken into account, and under what assumptions the calculations were performed. The PVSyst manual is an important resource to support that verification work.

Once you can read the PVSyst manual correctly, you will be able to move beyond merely being an operator in the study of photovoltaic power generation systems and come closer to being someone who understands and can explain the design conditions. Begin by mastering seven basic points, and, while referring to the necessary sections for each project, develop the ability to judge the validity of simulation results.