Is Surveying a Solar Power Plant Possible with Drones? 5 Comparison Points

Table of Contents

• Why drones are attracting attention for solar power plant surveying

• Comparison point 1: How efficiently can wide sites be understood?

• Comparison point 2: How well does it fit with terrain undulation and earthworks plans?

• Comparison point 3: At which stage should the required accuracy be ensured?

• Comparison point 4: Can it handle on-site detail work such as pile centers and boundaries?

• Comparison point 5: Can it be used for schedule management and as-built verification?

• Conclusion

Why drones are attracting attention for solar power plant surveying

In planning and constructing solar power plants, the quality of surveying broadly affects subsequent design, earthworks, mounting structure installation, wiring plans, and schedule management. Especially in recent years, many sites have large areas, internal elevation differences, or require layout considerations that utilize existing terrain, so the role required of surveying has become more than simply measuring distances or heights. In that context, drone surveying has gained attention as a way to quickly grasp large areas.

However, to be clear, surveying a solar power plant does not necessarily conclude with drones alone. In practice, it is more important to separate what drones are good at from what ground surveys, RTK, and on-site checks are good at, and use each accordingly. Use drones to quickly capture the overall terrain, scrutinize necessary spots on the ground, and secure the standards needed for design and construction with RTK or ground observations. Whether this division of roles can be achieved greatly affects the usability of survey results and the ease of subsequent construction.

On many solar power plant sites, simply creating a topographic map is often insufficient. Survey results are used continuously for pre-earthworks condition assessment, checking drainage directions, considering mounting structure row layouts, checking elevation differences on access routes, setting pile centers, monitoring construction progress, and as-built verification after completion. Therefore, rather than deciding which surveying method is superior in a simple manner, it is necessary to choose based on what you want to understand at each stage.

The reason drone surveying is considered convenient is that it makes it easy to view the site as a surface from above. Traditional ground surveying tends to record required points sequentially and, while highly accurate, can take time to review a wide site from an overview perspective. Drones, on the other hand, make it easy to grasp the overall flow of terrain, trends in elevation differences, the location of existing roads and waterways, slopes, and tree placements at once, so they are particularly powerful for initial assessments and overall comparisons.

What practitioners of solar power plants really want to know is not whether drones can be used, but to what extent they can be relied upon and where other surveying methods become necessary. Are the data sufficient to hand over to the design department? Can they be used directly for piling and mounting structure installation? Can on-site final checks be skipped? For such questions, neither a blanket endorsement of drones nor exclusive reliance on ground surveying is realistic; thinking in terms of comparisons by stage is more practical.

This article organizes the situations in which drones are effective for surveying solar power plants into five practical comparison points. It does not delve into detailed regulations or permit explanations, but focuses on how to use and divide roles on site. If you are about to conduct a site survey or earthworks planning, are unsure which surveying method to choose, or are considering introducing drones but want to clarify the differences with ground surveying, review the overall picture here.

Comparison point 1: How efficiently can wide sites be understood?

Candidate sites or construction areas for solar power plants often span wide areas, unlike small residential plots. Moreover, site shapes are not necessarily simple rectangles; earthworks areas, remaining forest, existing roads, slopes, drainage channels, and boundaries with adjacent land can be intricately interwoven. For such sites, whether you can efficiently grasp the overall picture is a major factor in selecting surveying methods.

In this respect, drone surveying is highly suitable. Because it captures the entire site from above, it is easier to quickly understand the current planform, trends in elevation differences, and positional relationships with surrounding features. Being able to confirm a wide area as a surface makes drones especially suited to initial comparisons for earthworks planning, panel layout, candidate access routes, and temporary yard locations. Terrain connections that are easy to overlook when walking the site are also easier to understand from an aerial perspective.

For example, part of a site may be relatively flat while suddenly dropping off near the edges, or the site may have subtle undulations that are hard to see. Such changes affect mounting structure row alignment, walkway planning, and drainage slope assessments. Even elements that take time to capture with point-based ground measurements can be grasped early on when captured as a surface by drone, enabling a quicker start on design drafts.

That said, ground surveying does not become unnecessary. Ground surveying is strong in situations that require reliably observing necessary points and accumulating detailed checks. While drones are effective for a rough understanding before entering the site, for actual design and construction it matters what accuracy is ensured at important points. A workflow that uses drones to grasp the overall site and then verifies priority spots on the ground based on those results tends to reduce wasted effort.

Also, survey results for solar power plants are often shared among multiple stakeholders. Because designers, earthworks teams, electrical contractors, and construction managers make decisions based on the same current-condition data, materials that show the whole site have high value. The way a site appears from drone-derived data makes it easier to share impressions of terrain that are hard to convey verbally, helping to reduce differences in site understanding. This is not just about saving survey time; it also has large benefits in preventing rework in later stages.

However, judging only by efficiency can lead to mistakes. Just because you can capture a wide area does not mean all required evaluation items are automatically satisfied. For example, obstacles hidden at ground level, conditions of existing structures, locations of boundary markers, and clearances from nearby objects can be difficult to judge without walking the site. In other words, drones are strong as an entry point to efficiently understand a wide site, but should be seen as a means to narrow down on-site checks rather than a replacement for them.

In practice, it is effective to first organize the overall current conditions with a drone and then extract priority verification areas from those results. For instance, identify areas with large elevation differences, parcels likely to require large earthworks, sections with severe slope or drainage conditions, or areas where connection to existing roads looks difficult, and then confirm those on the ground. Having an aerial overview before walking the site makes on-site inspections more focused and reduces the chance of missing checks compared with wandering the site with no prior information.

What matters in surveying solar power plants is not trying to solve everything with a single method from the start. Viewed on the axis of capturing wide areas, drones are very effective. However, that effectiveness is maximized when combined with ground surveying and RTK. Think of drones as quickly grasping the overall picture, ground surveys as filling in necessary points, and RTK as ensuring coordinate certainty—this division of roles is the most practical in the field.

Comparison point 2: How well does it fit with terrain undulation and earthworks plans?

Terrain conditions at solar power plant sites directly affect profitability and constructability. Large elevation differences within a site often increase earthwork volumes and may require slope and retaining wall considerations. If drainage directions are hard to read from the terrain, water flow and erosion risks during heavy rain must be considered. Therefore, it is important not only to measure site area but to understand how well undulation can be captured in three dimensions.

Here again, drone surveying aligns well with solar power plants. Data captured from above make it easy to perceive surface undulation and compare existing ground conditions across a wide area before earthworks. Ground-based methods can also capture elevation differences, but the more complex the undulation, the longer it takes to grasp overall continuity. Drones make it easier to understand the flow of terrain as a whole—ridges, valley-like drops, lowlands where water might collect, and boundaries between cut and fill areas.

In many cases, solar power plants aim to minimize earthworks while arranging rows of mounting structures stably. It is therefore important to identify early which parcels can use existing terrain for layout and which will incur significant earthwork. Drone surveying is well-suited for this comparative evaluation. When the current terrain view is organized, it becomes easier to propose panel row directions, walkway plans, and equipment placement candidates.

Drainage planning compatibility is also important. Solar power plants require considering rainwater flow across the entire site, and local ponding or concentrated surface flow can lead to long-term issues. Water flows that are hard to perceive from a few ground observations become easier to evaluate when the whole terrain undulation is visible. Of course, on-site confirmation is ultimately essential, but being able to identify where to pay attention early on is a major advantage.

However, being able to perceive undulation does not mean construction-related decisions can be made solely from drone data. For example, vegetation density, topsoil condition, muddy areas, boulders, and the condition of existing structures are factors that are difficult to judge from above. Ease of earthworks depends not only on terrain but also on actual ground conditions and heavy equipment routings during construction. Therefore, it is indispensable to use drones to capture the terrain skeleton and then confirm construction obstacles on the ground.

Also, long-term maintenance considerations should be kept in mind when reviewing terrain for solar power plants. Even if construction is straightforward, problems may arise during operation such as difficult access to inspection paths, muddy conditions after rain, or difficulty mowing near slopes. Drone surveying allows a bird’s-eye view of terrain that helps imagine not only construction-time but also maintenance-time circulation. This contributes to initial decisions with long-term operation in mind, not just design support.

Conversely, be careful not to be complacent about seemingly flat sites. For solar power plant earthworks, even slight elevation differences can affect row alignment and drainage slopes. A site that appears flat may still have biased drainage, local excess soil volumes, or require a lot of foundation height adjustment. Drone surveys, as a means to view the whole surface, are useful for quickly finding such subtle differences.

Nevertheless, despite their strength in capturing undulation, drones are not appropriate to entrust with final decisions on pile positions or near-structure proximity. Drones are strong for drafting earthwork plans and overall comparisons, but final construction condition confirmation needs to be judged on the ground. If the division is: read the large-scale terrain with drones and translate construction details with ground checks and RTK, drone surveying becomes a very usable tool for earthworks planning at solar power plants.

Comparison point 3: At which stage should the required accuracy be ensured?

A common misconception in solar power plant surveying is thinking the same accuracy is required at every stage. In reality, the meaning of required accuracy differs between the stage of understanding current conditions for comparison and the stage of specifying actual construction positions. The accuracy needed for overall planning is not the same as that needed for pile centers or equipment installation positions. Choosing surveying methods without clarifying this difference can lead to unnecessary effort or, conversely, insufficient accuracy.

Drone surveying excels at efficiently obtaining information needed for understanding site-wide terrain trends and layout consideration. However, in practice, when using survey data for position staking and construction standards, how to ensure coordinate reliability becomes important. In other words, you must consider to what degree drone-derived information can be connected to design and construction in terms of positional accuracy.

This is where linkage with RTK and control point management becomes crucial. For solar power plants, it is desirable that design drawings, site surveys, position staking, and as-built verification all connect under the same coordinate concept. If the standards differ between the current-condition survey stage and the construction stage, it may affect earthwork lines, pile center positions, walkway widths, and equipment spacing. When using drone surveying, it is important to secure ground-based references and, where necessary, verify positions with RTK to ensure consistency.

Practically, it is effective to manage accuracy in stages rather than uniformly. In the initial stage, the value lies in being able to compare wide ranges. This stage focuses on trends in site-wide elevation differences, available area tendencies, and extracting parcels that would require significant earthworks—areas where drones show strengths. Next, when design becomes more concrete, verify coordinates and heights of key points on the ground to improve consistency. During construction, use RTK and ground surveys for staking and verification. This flow allows accuracy to be managed without undue strain.

In solar power plants, row alignment, spacing, pile position deviation, and differences in earthwork surface heights can accumulate into problems in later stages. If the data used for initial site assessment and the standards used during construction are not linked, explaining discrepancies on site becomes difficult. Design personnel may be making decisions based on survey results while construction personnel are staking positions using different standards—this is a situation to avoid. For this reason, more important than whether you use drones is how you connect drone results to ground-based references.

When discussing accuracy, it is also necessary to consider not only numerical values but where errors matter. Differences that are negligible for a broad earthwork comparison might be unacceptable when checking pile centers or edge clearances. Conversely, if you only want to view overall trends, chasing high precision from the start wastes time and effort. The idea of securing the necessary accuracy where needed fits well with solar power plant practice.

When introducing drone surveying, avoid being overly swayed by the visually intuitive quality of deliverables. Aerial data are very easy to understand and convenient for sharing among stakeholders, but there are situations where additional verification is required before using them as construction standards. Being easy to view does not equate to being suitable for construction. That is why it is realistic to use drones as a planning-stage tool and secure construction-effective coordinate control with RTK and ground surveys.

As a result, the approach to accuracy in solar power plant surveying is not a binary choice between drones and ground surveys, but distributing responsibilities according to stage objectives. Use drones for overall comparison, RTK to secure the reference, and ground surveys for final detailed checks. This combination makes it easier to balance speed and reliability.

Comparison point 4: Can it handle on-site detail work such as pile centers and boundaries?

Surveying for solar power plants involves not only understanding current conditions but also many on-site detailed tasks. Typical tasks include staking pile centers, checking boundaries, fine-tuning equipment placement, confirming clearances from existing objects, and examining passage widths and working spaces. These tasks ultimately require in-person site judgment and directly tie into construction, so they are hard to complete with drones alone.

Regarding pile centers, pile position accuracy has a large impact on later stages for solar power plants. If pile positions are off, row alignment of mounting structures is affected, increasing the burden of panel layout and component adjustments. Therefore, staking pile centers needs to proceed with clear on-site references. Drones can capture the overall placement tendency, but actual pile center work relies mainly on RTK and on-site position verification.

Boundary checks are similar. Because solar power plants cover large land areas, understanding not only parts of the site but the entire perimeter is important. Even if a design drawing looks fine, on-site checks need to verify boundary marker positions, relationships with existing fences, elevation differences with adjacent land, and whether there is working space. Aerial viewpoints help organize overall relations, but final decisions near boundaries must be refined on site. During construction, whether a few tens of centimeters (several tens of centimeters (several inches)) of clearance exists can affect heavy equipment operations and maintenance access, so walking and confirming has high value.

On-site detail work also includes many elements that are not obvious on drawings. Examples include muddy ground, boulders, felled wood debris, temporary structures, traces of existing utility lines, steep slopes that are hard to enter, and narrowness that limits machinery access. These small site conditions accumulate to affect constructability at solar power plants. Drones are suited to organizing what can be seen from above, but they have limits in reading ground-level construction conditions.

The important point here is that using drones does not eliminate the need for on-site checks, but rather improves the quality of those checks. With an advance grasp of the overall picture, on-site personnel can clearly know what to focus on. For example, you can walk the site focusing on whether rows near boundaries have sufficient working clearance, whether edge areas have drainage issues, whether planned equipment locations are easy to deliver to, or whether safe work is possible near slope shoulders.

Compatibility with RTK also matters. In situations where you need to verify positions or set provisional positions on site, having means to immediately handle coordinates makes work flow more smoothly. If the drone-organized overall data and RTK-verified on-site points are handled in the same coordinate system, it becomes easier to reconcile with design and make change decisions. Particularly for solar power plants, when design changes occur in part of the project, you need to understand the impact on the whole. When aerial overall understanding and on-site coordinate checks are connected, decisions are made faster.

For site personnel, what matters is not which method is superior but what is needed for each task. Staking pile centers, boundary checks, proximity confirmations, and clearance checks will continue to be dominated by ground verification. At the same time, deciding which places to prioritize for detailed checks is a role drones can play. In other words, drones do not replace on-site work but create prerequisite information to help carry it out efficiently.

To avoid failure in surveying solar power plants, do not be overly reassured by drone results. Even if something looks tidy on a screen, actual site dimensional and operational impressions can differ. Construction is ultimately executed on the ground. Therefore, the three-pronged approach of organizing the whole with drones, aligning positions with RTK, and confirming footing on the ground is the most robust practical procedure.

Comparison point 5: Can it be used up to schedule management and as-built verification?

Surveying for solar power plants does not end at the planning stage. As earthworks begin, piling progresses, and mounting structures and wiring are installed, survey results can be used for schedule management and as-built verification. Therefore, when choosing a surveying method, an important comparison axis is whether the method can be reused not only for initial surveys but also during construction and after completion.

Drone surveying has advantages in this continuous-use aspect as well. It is easy to periodically capture changes across a wide site, making it simple to check earthwork progress and soil volume changes, the state of temporary roads and material yards, and shape changes related to drainage. Solar power plant work areas tend to be widely distributed, and it can be difficult for site supervisors to grasp the whole just by walking. In such cases, aerial information helps capture site changes more readily.

For example, drones help verify whether earthworks are progressing as planned, whether there are imbalances between cut and fill volumes, whether slope shapes match expectations, and whether heavy equipment routes follow plans. Aerial materials are also effective when sharing site status at progress meetings. Because it is hard to judge a solar site by looking at only part of it, the ability to understand progress by work area and remaining works in relation to the whole has practical value.

On the other hand, as-built verification and checking construction accuracy still require on-the-ground confirmation. Items directly tied to construction quality—mounting structure references and pile positions, clearances of wiring routes, and consistency of equipment installation positions—must be reliably checked on site. Drones are suitable for observing overall progress and shape trends, but they are not intended to take on final verification of individual construction points. While they are strong for schedule management, detailed quality control must be combined with ground checks.

Construction sites change daily. Temporary structures appear, materials accumulate, work routes shift, and weather has an impact. To decide what to check first amid these changes, fixed-point aerial capture is useful. Particularly on large sites like solar power plants, delays or defects in one area can affect the whole. Using drones to grasp overall status and RTK or ground surveys to confirm problem spots raises the accuracy of schedule management.

Additionally, having records of site conditions during construction is valuable at handover and in the early stages of maintenance. It is easy to understand which areas were earthworked in which ways, where equipment was placed, and how access routes and drainage were completed. For maintenance, when issues occur you need to consider causes in the context of the whole site. If information from pre-construction, during construction, and post-completion is organized sequentially, it also aids future inspection and repair decisions.

Again, the key is not to try to complete schedule management solely with drones. Aerial information is highly convenient, but determining which tasks are complete, which parts need correction, and which locations deviate from design ultimately requires on-site refinement. Drones are strong for visualizing schedules, while ground surveys and RTK are strong for ensuring construction accuracy. Understanding and operating with this division allows survey results to truly serve the field.

If you view surveying for solar power plants as a one-off task, the discussion tends to be about which method is most convenient. In reality, surveying is a continuous information base that connects current-condition assessment to design, construction, as-built verification, and maintenance. From this perspective, drones are effective as the backbone for overall understanding and schedule sharing, while RTK and ground surveys support reliable on-site decisions. Rather than treating them separately, it is important to combine them into a single workflow.

Conclusion

If asked whether surveying a solar power plant is possible with drones, the answer is: "Many parts are possible, but not everything can be replaced." Drones are highly effective for overall site understanding, organizing terrain undulation, initial comparisons for earthworks planning, and visualizing schedule management. Their ability to capture the whole site as a surface is a major strength for wide-area projects like solar power plants.

On the other hand, on-the-ground tasks such as staking pile centers, refining areas near boundaries, checking clearances, coordinate control used as construction standards, and detailed as-built checks require ground surveys, RTK, and on-site verification. Drones are suitable for quickly grasping the whole and organizing where to focus checks. Final on-site judgments remain the domain of ground verification.

The important point is to divide roles by stage rather than choosing between drones or ground surveying. Use drones to grasp the whole in initial surveys, secure coordinates for critical points with RTK, and confirm final construction decisions on site. This flow not only improves surveying efficiency but also aids consistency with design, eases construction, and helps prevent rework.

Survey results at solar power plant sites are not only for drawing creation. They are expected to function as a common information base covering earthworks, mounting structures, wiring, and maintenance. Therefore, more important than producing visually pleasing deliverables is linking them in a form usable on site. If you introduce drone surveying, think about how to connect its strength in overall understanding with ground surveys and RTK; doing so will greatly change its practical usefulness.

If you want to perform coordinate checks and position staking more nimbly on site, combining drone-derived overall information with locally usable high-precision positioning is an effective idea. For instance, in situations where you want to streamline site checks, simple position staking, and verification against design coordinates, combining drone surveying with an on-site friendly high-precision positioning method such as LRTK (iPhone-mounted GNSS high-precision positioning device) makes it easier to translate drone results into practical use. If you want to leverage solar power plant surveying as information that links investigation, design, and construction rather than ending with the survey, choosing methods based on such role divisions is important.