How to Learn PVSyst Quickly｜5-Step Learning Sequence Useful for Practical Work

Table of Contents

• The order of study is important to learn PVSyst quickly

• Step 1: First grasp the screen layout and basic terminology

• Step 2: Create one small model to understand the overall flow

• Step 3: Understand the meaning of meteorological data and installation conditions

• Step 4: Learn array configuration and loss settings from a practical standpoint

• Step 5: Be able to read and explain the result reports

• Common stumbling points when learning PVSyst

• Practice methods to quickly become proficient for practical work

• Reflect on-site conditions correctly without relying solely on PVSyst

• Summary

The order of study is important for learning PVSyst quickly

If you want to learn PVSyst quickly, the first thing to be aware of is "don't learn every feature in order." When learning specialized software, many people tend to check the menus from the top down or investigate each setting one by one. However, what is needed in practice is not knowledge of all features, but the operations and judgments required to carry a project through from start to finish.

In solar power generation simulation work, you first choose the site, set the meteorological data, enter the azimuth and tilt angles, match the conditions for the modules and power conditioners, configure the loss conditions, and check the calculation results. After that, you evaluate whether the estimated generation is reasonable, whether the losses are not too large, whether oversizing and clipping are within acceptable ranges, and whether you can explain the results in proposal materials. In other words, the order in which you should learn is not the software’s menu order, but the actual workflow of handling a project.

People who learn PVSyst quickly don't try to perfect every detailed setting from the start; they first build a simple grid-connected model, run the simulation, and read the results report. After that, they check why the energy production turned out as it did and how changing each setting affects the results. By proceeding this way, the meaning of each setting becomes established not as isolated knowledge but as knowledge connected to the outcomes.

On the other hand, if you dig too deeply into individual settings like temperature losses, mismatch losses, wiring losses, soiling losses, and detailed shading settings right from the start, time will pass without you seeing the big picture. Of course, these settings are very important in practice. However, in the initial learning phase, prioritize "where to enter them", "which parts of the results they affect", and "how much attention to pay to them in practice", and build up the detailed theory later.

When learning PVSyst, it is effective to first create a single standard model and then duplicate it many times while changing the conditions. For example, practicing by changing only the tilt angle at the same site, only the azimuth, only the DC/AC ratio, or only the loss conditions makes it easier to see the relationship between inputs and results. This develops practical intuition—not just memorizing operational procedures—such as “changing this condition increases energy production,” “increasing this loss reduces annual energy production,” and “adding shading conditions produces distinctive monthly loss patterns.”

The purpose of learning PVSyst quickly is not merely to become able to operate the software, but to be able to create decision-making materials that can be used in design and proposals. For that reason, it is important from the early stages of learning to be mindful of the final report and the situations in which you will present or explain the results. If you learn while thinking about which input conditions you need to explain to others, which results to use as comparison materials, and which figures are likely to be questioned during internal review or when explaining to clients, the knowledge you acquire will be directly applicable to practical work.

Step 1: First grasp the screen layout and basic terminology

The first step is to grasp PVSyst's screen layout and basic terminology. What is important here is not to try to understand every detailed setting, but to get a sense of the overall workflow. In PVSyst, elements such as the project, location, meteorological data, azimuth, tilt angle, system configuration, losses, shading, and simulation results combine to form a single model. If you organize in advance what each of these means, later operations will be easier to understand.

First, it's important to understand the concepts of projects and variants. A project is the container for the entire case and the unit that manages the site and basic information. A variant, on the other hand, is like a simulation scenario within the same project that changes certain conditions. For example, when comparing proposals on the same site that alter the tilt angle, vary the panel capacity, or change the oversizing ratio, you create multiple variants and compare the results. If you don't understand this structure, you won't know which condition was changed, making subsequent comparisons difficult.

Next, let’s confirm the meanings of azimuth angle and tilt angle. The azimuth angle indicates which direction the solar panels face, and the tilt angle indicates how much the panels are inclined. These have a large impact on power generation. In practice, optimal installation conditions vary depending on roof orientation, racking design conditions, land shape, considerations for snow and wind loads, maintenance access routes, and so on. In PVSyst they are entered as numerical values, but behind those numbers are the site conditions and design policies.

Also, it is important to clarify terms such as array, string, module, inverter, DC capacity, AC capacity, and DC/AC ratio early on. An array is a grouping of solar modules, a string is a unit of modules connected in series, DC capacity refers to the capacity on the solar module (DC) side, and AC capacity refers to the capacity on the inverter (conversion equipment) side. The DC/AC ratio is important for understanding the relationship between module capacity and inverter capacity. If you proceed with operations without understanding these relationships, you may be able to perform the calculations but will not be able to explain the meaning of the results.

First, grasp the basic terms related to losses in broad strokes. In PVSyst, various losses are reflected in the results, such as losses due to temperature, wiring losses, equipment conversion losses, mismatch losses, soiling losses, and shading losses. At the beginner stage, there is no need to memorize each theoretical formula in detail. Above all, it is important to have the sense that loss settings are a key factor for bringing estimated generation closer to reality, and that underestimating or overestimating them will affect the accuracy of proposals.

When learning the screen layout, it is effective to proceed while taking notes on what to set on each screen. If you broadly classify screens into those for setting location and weather data, setting installation azimuth and tilt, entering equipment configuration, setting losses, and checking calculation results, you will be less likely to become confused during operation. You do not need to memorize all the menu names from the start, but it is important to understand which category a given task belongs to.

When learning PVSyst quickly, it can be effective to translate basic terms into the terminology used in your own work. For example, for proposal staff, think of them as "assumptions about energy production to explain to the customer"; for design staff, "conditions to reconcile with drawings and equipment specifications"; and for construction management staff, "installation conditions that will actually be reproduced on site." Thinking this way lets you understand them not as mere inputs to the software but as practical checklist items for day-to-day work.

Step 2: Create a single small model to grasp the overall flow

After reviewing the basic terminology, next create one small model. The purpose here is not to produce a perfect model, but to go through the entire process once—from creating the project to checking the simulation results. To learn PVSyst quickly, it is more important to make time early to actually work hands-on and complete a single calculation than to spend time reading.

The first model should be built under conditions as simple as possible. Large-scale, complex projects, roofs with multiple orientations, detailed shading configurations, and setups that include storage batteries or self-consumption are not suitable for initial learning. First, assume a single orientation, a single tilt, and a standard grid-connected model, and input the site, meteorological data, installation conditions, equipment configuration, and loss conditions to perform the calculations. Avoiding complex conditions makes it easier to see which inputs affect which results.

When creating a model, you first set the location and select the meteorological data. Next, you enter the solar panel's azimuth and tilt angles. After that, you configure the module capacity, number of modules, string layout, and inverter conditions, and check the basic losses. Finally, you run the simulation and review the annual and monthly energy production, loss breakdown, performance ratio, and so on. Simply going through this sequence once makes the overall picture of PVSyst much clearer.

In initial models, errors and warnings may appear. For example, warnings that the string voltage does not fall within the required range, there are inconsistencies in the equipment configuration, input conditions are insufficient, or settings conflict with one another. Beginners may feel uneasy, but these are important learning materials. When a warning appears, rather than immediately investigating every detailed cause, check "which category of settings the problem is occurring in." Even being able to classify whether it is equipment configuration, meteorological data, losses, or shading will improve your practical response capability.

After you create a model, always save it and duplicate it to use for practicing condition changes. If you keep the first model as the reference model, it will be easier to compare later.

For example, if you change the tilt angle by 10 degrees, shift the azimuth east or west, increase the DC capacity, or make the loss conditions more severe, changing one item at a time and observing the results makes it easier to understand how PVSyst behaves.

The important thing is not to change many conditions at once. In real work you may change multiple conditions simultaneously, but doing so during the learning stage makes it unclear which factor caused the change in power generation. To learn more quickly, even if it seems roundabout, it is more efficient to change and check one condition at a time. This will build your ability to interpret results, rather than just memorizing operating procedures.

When practicing building small models, it is also important to produce the report. PVSyst is software that is often used not only to perform calculations but also to explain the results. The report organizes the input conditions, system configuration, energy generation, losses, and performance indicators. Developing the habit of reviewing the report from the initial stages helps you understand which inputs will be reflected in the final documentation. This directly connects to preparing proposals, internal reviews, and customer presentations.

Step 3: Understand the meaning of meteorological data and installation conditions

One thing you should understand early on when learning how to use PVSyst is the meteorological data and installation conditions. Power generation simulations can vary significantly depending on conditions such as incident solar irradiance, ambient temperature, installation azimuth, tilt angle, and the surrounding environment. In other words, even if you operate the software correctly, if the input assumptions deviate from reality, the results will be difficult to use in practice.

Meteorological data are a crucial factor forming the basis of annual power generation. If solar irradiance or temperature data differ, the generated output will change even with the same installed capacity. Beginners tend to stop at simply selecting meteorological data, but in practice it is necessary to check which location's data were used, how far it is from the site, and whether there are any issues with the representativeness of the data. Especially in mountainous areas, coastal areas, snowy regions, and areas prone to fog or clouds, using data from nearby locations can still result in differences from actual conditions.

For installation conditions, azimuth and tilt angle are the most basic items. Generally, the orientation and slope of solar panels directly affect energy production. While being closer to south-facing is often more advantageous, depending on roof shape, site conditions, grid connection conditions, and the relationship with the demand curve, you should not simply judge by annual energy production alone. For example, if self-consumption is prioritized, the time-of-day distribution of generation can be important. To learn PVSyst quickly, it is important to make a habit of checking not only annual energy production but also monthly and time-of-day trends when changing azimuth and tilt angles.

The tilt angle affects not only energy production but also constructability, racking conditions, snow, wind, and maintainability. In PVSyst you can calculate it by entering numerical values, but you must verify whether that angle is actually feasible to construct on site and whether it is consistent with the drawings and the conditions found in the site survey. During the learning phase, changing the tilt angle a few times and observing the differences in energy production will help you develop an intuitive understanding of the impact of the installation angle.

Shading conditions are also important in practice. Buildings, trees, surrounding equipment, terrain, and shading between rows of racking all affect power generation. Beginners can postpone configuring shading settings while learning the basic operations, but when using the tool for real-world proposals or designs you must always determine whether it is acceptable to ignore shading. On a wide site with almost no shading, simplified settings may not cause major problems, but for rooftop installations or sites with many surrounding obstructions, shading can significantly affect the results.

When learning meteorological data and installation conditions, it is important to treat input values not as "numbers in the software" but as "information to be obtained on site." Azimuth must be confirmed from drawings or on-site measurements, and tilt angle is related to roof pitch and racking design. The positions and heights of surrounding obstacles, the slope of the terrain, and the spacing of module layouts are also tied to site conditions. The more you learn to operate PVSyst, the more you will realize that the accuracy of on-site information determines the reliability of the results.

As a practice to learn quickly, one method is to compare results using the same model while changing the meteorological data, the azimuth, and the tilt angle one at a time. For example, check how annual energy production and monthly generation change when the azimuth is shifted slightly to the east versus to the west, and when the tilt angle is lowered versus raised. By doing this exercise, you will understand that installation conditions are not just input fields but material for design decisions.

Step 4: Learn array configuration and loss settings from a practitioner's perspective

To use PVSyst in practical work, understanding array configuration and loss settings is indispensable. This is a part where beginners often stumble, and at the same time it’s where practical differences become apparent. The energy production result is not determined solely by installed capacity. Module count, string configuration, the combination with power conversion equipment, wiring conditions, temperature conditions, mismatch, soiling, shading, and many other factors accumulate to determine the final energy output.

In the array configuration, check the number of modules in series and in parallel, the input conditions of the converter, the voltage range, the current range, and the capacity ratio. In PVSyst, a warning may appear if the conditions do not match. Beginners tend to treat warnings as mere errors, but in practice they may indicate a design inconsistency. For example, if the number of modules in series is too low or too high, voltage conditions can become problematic at low or high temperatures. Even if the simulation appears to be valid, if it does not fit the specification range of the actual equipment, the design needs to be reviewed.

The DC/AC ratio is also an item frequently checked in practice. It is common to design the DC-side module capacity to be larger than the conversion capacity on the AC side, but if it is made excessively large it can increase output curtailment and clipping. On the other hand, within an appropriate range it can be advantageous in terms of plant utilization and energy generation. When learning PVSyst, it is important not just to look at the ratio number but to check the results report to see how much loss is occurring.

When configuring loss settings, it is efficient to understand the items in the order they are most commonly used in practice. Temperature loss deals with the impact on output caused by an increase in module temperature. It is related to installation method, ventilation conditions, ambient temperature, and so on. Temperature conditions can differ between installations placed close to the roof and racking installations with good ventilation. Wiring loss is related to cable length, cross-sectional area, current conditions, and so on. Mismatch loss is the loss that occurs due to differences in characteristics between modules and variations between strings. Soiling loss varies depending on dust, pollen, bird droppings, dirt after snowfall, the surrounding environment, and similar factors.

Not all of these losses can be measured directly. Therefore, in practice you will set reasonable values based on standard values, internal company standards, past projects, and on-site conditions. To learn PVSyst quickly, rather than memorizing loss values it is important to be conscious of “what this loss originates from,” “where increasing it will affect the results,” and “whether you have a rationale you can explain to customers and internally.”

Shading losses are handled differently depending on the design conditions. For projects with few surrounding obstructions, a simple check may be sufficient, but when buildings or equipment are nearby, when there are multiple roof surfaces, or when racking rows are densely packed, the effects of shading need to be examined carefully. Shading can affect not only annual energy production but also be biased toward certain seasons or times of day. Therefore, in reports it is important to review not only annual values but also monthly trends and the breakdown of losses.

When learning array configuration and loss settings, you will internalize them faster if you create your own checklist for practical use. For example: whether the number of modules matches the drawings, whether the number of modules in series is within the specification range, whether the DC/AC ratio meets internal standards, whether wiring losses are not underestimated, whether there is justification for ignoring shading conditions, and whether soiling losses are reasonable given the site environment. Rather than learning how to use PVSyst, it is important to shift to the mindset of using PVSyst to perform practical checks.

Step 5: Be able to read and explain the results report

What's ultimately important to focus on when learning PVSyst quickly is being able to read the result reports and explain them. Even if you can operate the software, if you cannot explain what the reports mean, you cannot be said to have mastered its practical use. In particular, in proposal work and design reviews you need to be able to explain not only "what the annual energy production is" but also "why that production occurs," "which losses are large," "whether the assumptions are reasonable," and "how it differs from alternative options."

The first thing to check is the annual energy generation. This is the most straightforward result, but it is not sufficient on its own. Even with the same annual generation, its meaning changes if the installed capacity, site, azimuth, tilt, loss conditions, or shading conditions differ. When reviewing annual generation, simultaneously check the generation per unit of installed capacity and performance indicators to determine whether the level is appropriate for the project.

Next, check the monthly generation. By looking at monthly trends, it becomes easier to grasp whether the system performs better in summer, whether there is a large drop in winter, or whether shadows, snowfall, or orientation are having an effect. Imbalances that are not visible from annual values alone can often be seen when viewed month by month. In particular, when considering self-consumption or demand-linked operation, monthly and time-of-day generation trends can be more important than the annual total.

Always check the loss breakdown. The PVSyst report shows where and how much loss occurs in the conversion process from solar irradiance to the final energy output. Being able to read this makes it easier to pinpoint the causes of low energy production. For example, you can determine whether temperature losses are large, shading losses are significant, conversion losses stand out, or whether wiring or mismatch settings are having an impact.

The performance ratio is also an important indicator. Unlike simple energy output, the performance ratio is a measure of how efficiently a system is generating electricity. However, you should not judge performance solely by the performance ratio; it needs to be considered together with meteorological conditions, installation conditions, loss settings, and shading conditions. When you are just beginning to learn PVSyst, instead of stopping at the performance ratio number, practice reading it together with the loss breakdown to deepen your understanding.

To be able to explain a report, practicing by comparing a standard model and modified models is effective. For example, create a baseline model, a tilt-angle modification model, an azimuth-angle modification model, and a loss-condition modification model, and compare each of their results. Then try drafting explanatory sentences such as, "This option increases annual energy production, but alignment with construction conditions is required," "In this option shading losses have increased, so the layout needs to be reconsidered," and "Under this condition clipping has increased, so confirm the validity of the capacity ratio."

In practice, you need to convert PVSyst results into language the other party can understand, rather than presenting them as-is. Simply listing technical loss names and indicators may not be easily understood by customers or stakeholders. For example, for shading losses you can explain, "Due to nearby obstructions and inter-row shading, generation may decrease during certain times of day." For temperature losses you can express, "In seasons when module temperature rises, output will be somewhat reduced even if solar irradiance is high."

To learn PVSyst quickly, it is important not just to read the results but to repeatedly practice explaining them in your own words. If you can look at the numbers in a report and explain which input conditions led to those results, your practical applicability will increase greatly.

Common Pitfalls When Learning PVSyst

There are several points where people learning PVSyst tend to get stuck. The most common is trying to perfect detailed settings from the very beginning and losing sight of the overall workflow. PVSyst is highly specialized and has many configuration items, so attempting to understand everything before operating takes time. At first, prioritize building a standard model and running the calculations, and then delve deeper into the meaning of the settings—it’s more efficient that way.

One common stumbling block that comes next is dealing with warning messages. When a warning appears, work can stop because you don’t know what to fix. In such cases, before reading the warning in detail, determine which category of problem it belongs to. Distinguishing whether it’s an equipment configuration issue, insufficient input conditions, a setting value outside the allowable range, or a model inconsistency makes it easier to respond. Rather than ignoring warnings and continuing calculations, you should at least check that they do not pose any practical problems.

Also, meteorological data and installation conditions can sometimes be overlooked. PVSyst is a powerful software, but if the input conditions are misaligned with the actual site, the results will be off. In particular, azimuth angle, tilt angle, shading, surrounding obstacles, and the effects of snow and soiling are strongly linked to on-site information. It is important to adopt the mindset that something is correct not because it can be set in the software, but because it is consistent with the site conditions.

Loss settings are also an area where beginners can easily get confused. Which losses to set and to what extent depends on project conditions, internal standards, and past track records. The important point here is not to assume there is a single correct answer. In practice, you should set them with a clear rationale, perform sensitivity analysis as needed, and be able to explain their impact on the results.

Furthermore, you should be careful not to judge the results report based only on annual energy production. Annual energy production is important, but on its own it does not reveal the causes of losses or design issues. By reviewing monthly energy production, loss breakdown, performance ratio, clipping, the effects of shading, and so on together, you can make decisions that are useful in practice.

When you're trying to learn PVSyst quickly, it's especially important not to focus only on the operating procedures. By learning operation, input conditions, how to interpret the results, and how to explain them as an integrated whole, it becomes established as a practical skill rather than merely software operation.

Practice Methods to Quickly Become Useful on the Job

To get up to speed using PVSyst in real-world work quickly, it's important to make your training exercises as close to actual projects as possible. Simply following the steps won't prepare you to handle situations when conditions change slightly in a real project. Therefore, creating a baseline model and repeatedly practicing by comparing it with changed conditions is effective.

First, create a standard grid-connected model. Next, duplicate that model and change only the azimuth angle. Then, with another duplicate change only the tilt angle. After that, change parameters one by one—DC/AC ratio, wiring losses, soiling losses, shading conditions, etc.—and compare the results. This method allows you to systematically understand how each condition affects energy production and losses.

When practicing, we recommend that you always write a short explanatory sentence after viewing the results. For example, “Increasing the tilt angle improves winter power generation, but it may not make a large difference in the annual total,” “Shifting the azimuth slightly westward changes the afternoon generation pattern,” “Making the loss conditions stricter reduces the annual power generation but makes it easier to explain as an assumption closer to on‑site conditions.” By practicing these explanations, you will simultaneously develop the ability to read reports and the ability to incorporate them into proposal materials.

Creating templates for input conditions that are frequently used in practice is also effective. If you set them from scratch every time, omissions and inconsistencies in the conditions are likely to occur. Organizing items such as locations, installation conditions, loss conditions, and report verification items as internal standard procedures will help improve quality not only for learners but for the entire team.

As practice that approximates real projects, you can also create comparison materials by setting hypothetical conditions. For example, on the same site you might create three scenarios—changing equipment capacity, changing tilt angle, and including shading conditions—and consider which proposal is easiest to present. In this case, the scenario with the highest energy yield is not necessarily the best. Practical judgments vary depending on constructability, cost, maintainability, available installation area, grid conditions, and the purpose of self-consumption. It is important to use PVSyst as a tool to produce the information needed for those judgments.

To accelerate learning, it is beneficial to intentionally experience failure patterns. For example, practice deliberately setting the number of strings incorrectly to observe warnings, comparing results calculated without shading conditions to those calculated with them, and comparing cases where losses are made unrealistically small with cases where they are set to realistic values. By learning not only the correct procedures but also how incorrect settings manifest in results, you improve your ability to check and verify work in practical situations.

PVSyst is not software you can fully learn in one go. It’s the type of program whose understanding deepens as you work on more projects. Therefore, your initial goal should not be to “understand everything,” but to “create a standard project, perform the calculations, and explain the results.” Once you reach this stage, you can acquire the applied knowledge required for practical work as you add it for each project.

Accurately Reflect On-Site Conditions Without Relying Solely on PVSyst

What you must never forget when mastering PVSyst is that the quality of the simulation results is heavily dependent on the quality of the local site conditions you input. No matter how proficient you are at using the software, if information such as azimuth, tilt angle, surrounding obstructions, terrain, installation location, spacing, and rack height is inaccurate, the reliability of the results will be reduced.

Especially in photovoltaic systems, slight differences in on-site conditions can affect design and power generation estimates. The orientation of roof surfaces, differences in ground elevation, the positions of surrounding buildings and trees, the arrangement of racking rows, maintenance access paths, and distances to boundaries may not be fully captured by drawings alone. Accurately reflecting information obtained from on-site surveys is important for improving the accuracy when using PVSyst.

For example, in shadow analysis it is difficult to make an accurate assessment if the height and position of obstacles remain unclear. In projects where the slope of the terrain or post-development elevations change, the conditions of the installation surface also change. For rooftop installations, it is necessary to consider roof pitch, equipment, handrails, penthouses, and the influence of adjacent buildings. The values entered into PVSyst become meaningful only when they are tied to on-site verification, surveying, and drawing checks.

Therefore, the sooner a practitioner becomes proficient in PVSyst, the more they need to be mindful not just of operating the software but also of how to collect on-site information. Understanding what information to obtain on-site that can be used as input for PVSyst reduces omissions in surveys. Accurately determining azimuth, tilt, height, obstacles, terrain, boundaries, and the available installation area will make the simulation assumptions clearer.

A positioning environment that enables high-precision acquisition of local location and terrain information is useful here. LRTK, as an iPhone-mounted GNSS high-precision positioning device, can streamline on-site coordinate acquisition and position verification. When considering photovoltaic power generation facilities, there are many situations that require precise handling of positions: the location of candidate installation sites, checks near boundaries, recording surrounding obstacles, geotagging site photographs, and cross-checking with design conditions. As a preliminary step before running simulations in PVSyst, correctly understanding site conditions and clarifying the basis for input parameters leads to improved reliability of power generation assessments.

PVSyst is powerful for power generation simulations, but it is not a tool for field measurements. Conversely, improving the accuracy of on-site positioning and recording makes it easier to enhance the accuracy of the conditions entered into PVSyst. To raise the quality of designs and proposals, it is important not to treat simulation and on-site measurement separately, but to establish a workflow that reflects accurate information obtained in the field in the simulation.

Summary

The fastest way to learn PVSyst is not to memorize all of its functions, but to learn in the order they are used in practice. First, grasp the screen layout and basic terminology, create one small model, and understand the meaning of the meteorological data and installation conditions. Then, review the array configuration and loss settings from a practical perspective, and finally aim to be able to read the result reports and explain them.

Beginners do not need to understand everything perfectly from the start. Rather, creating a standard model, running calculations, and comparing the results while changing one condition at a time makes it easier to acquire practical intuition in a short period. When learning PVSyst, it is important to learn the operating procedures, input conditions, how to read the results, and how to explain them as an integrated whole.

Also, PVSyst results are heavily dependent on the quality of the input conditions. It is essential not only to correctly handle meteorological data, azimuth, tilt, shading, loss settings, and equipment configuration, but also to accurately understand the site’s location, terrain, obstacles, and installation conditions. Rather than judging solely by the numbers in the software, being able to explain which on‑site information those numbers are based on will increase the reliability of the simulation results.

In the design and proposal process for solar power systems, combining energy-yield simulations using PVSyst with an accurate understanding of on-site conditions leads to improved professional quality. By utilizing an iPhone-mounted, high-precision GNSS positioning device such as LRTK, you can streamline on-site coordinate acquisition and location recording, making verification of design conditions and simulation assumptions smoother. Not only by learning PVSyst quickly, but also by establishing a system that correctly reflects on-site information, it becomes easier to carry out consistently high-accuracy work from energy-yield assessment and design review through to the preparation of proposal documents.