6 Benefits of Drone Surveys That Solar Power Plant Management Companies Should Know

For companies that manage solar power plants, understanding on-site conditions and reflecting them in maintenance plans is fundamental to stable operation. Declines in power generation, poor drainage, deformations around slopes and mounting structures, and the effects of weeds and sediment can all be easy to overlook with routine inspections alone. One method being used to address this is drone surveying, which allows the entire plant to be viewed from above. In this article, we explain from a practical perspective six benefits that solar power plant management companies can gain by utilizing drone surveying.

Table of Contents

• Why drone surveying is gaining attention in solar power plant management

• Benefit 1 Easy to grasp the overall picture quickly

• Benefit 2: Inspection records can be easily kept as objective data

• Benefit 3: Easy to identify signs of poor drainage and changes in terrain.

• Benefit 4 Easier to assess the impact of weeds and nearby obstacles

• Benefit 5: Easier to review maintenance plans and priorities

• Benefit 6: Easier to create explanatory materials for stakeholders

• Considerations When Implementing Drone Surveying

• Summary

Why Drone Surveying Is Gaining Attention in Solar Power Plant Management

In managing a solar power plant, it is essential not only to inspect the power generation equipment itself but also to understand the condition of the entire site. The range of items to check is wide—panels, mounting structures, junction boxes, collection equipment, maintenance walkways, drainage facilities, slopes, fences, surrounding trees, and more—and the larger the plant, the more time and effort ground patrols alone require.

In particular, at solar power plants installed in mountainous areas, on slopes, or on graded land, terrain and drainage conditions can affect operations. Changes such as watercourses changing after heavy rain, sediment flowing into access paths, parts of slopes being scoured, or deposits accumulating in drainage channels are not easily noticeable at an early stage. However, if left unaddressed, they can lead to reduced accessibility of inspection paths, muddy conditions around mounting structures, sediment accumulation near fences, and decreased safety around equipment.

Drone surveying is effective as a means of obtaining an overview of the condition of an entire site. By utilizing images captured from above and terrain data created as needed, it becomes easier to detect changes that are difficult to grasp by walking the site alone. Of course, drone surveying cannot replace all equipment inspections. Electrical checks, verification of connections, detection of abnormal noises or odors, and inspection of equipment interiors still require traditional on-site specialist inspections.

On the other hand, when a management company is developing a maintenance plan, it is important to organize the current condition of the entire power plant. Wide-area information is useful for deciding which sections should be patrolled more intensively, where drainage measures are needed, which areas should be prioritized for weeding, and which locations should be rechecked at the next inspection. Drone surveying is a practical means of increasing the information available for those decisions.

The advantages for management companies of solar power plants in utilizing drone surveying are not limited to simply being able to view things from the air. It can be expected to improve the overall quality of management tasks by making record keeping easier, comparisons simpler, sharing with stakeholders more straightforward, and incorporation into maintenance planning more seamless. Below, we will go through six benefits that operational staff should be aware of.

Benefit 1: Easier to grasp the overall situation in a short time

A major advantage of drone surveying for solar power plants is that it makes it easy to inspect large sites from the air in a short time. During ground patrols, personnel move along maintenance walkways while checking each piece of equipment, so their viewpoint is inevitably limited. Areas such as the far side of panel rows, the tops of slopes, the perimeter along fences, and drainage channels set away from paths are locations that are easily overlooked even when walking the site.

By utilizing drones, you can record images that provide an aerial overview of the entire power plant. It becomes easier to check, on a site-wide basis, the condition of panel layouts, the state of pathways, the extent of grass overgrowth, low spots where drainage tends to flow, and areas where sediment is likely to accumulate. This is especially useful for power plants divided into multiple sections, as it makes it easier to compare the condition of each section and helps prioritize inspection rounds.

Inspections from the ground can lead to differences in the areas checked depending on the inspector’s experience and the routes they take. While on-site walking inspections are of course important, recording an entire power plant from the same perspective is not easy. By combining drone surveying, you can separate the aerial overview from detailed on-the-ground checks. If you first extract areas of concern from the air and then prioritize those areas for ground inspection, you can make more effective use of limited time.

Also, at solar power plants the way the site looks changes depending on the weather and the season. During the rainy season and after typhoons, drainage and sediment conditions are prone to change, and in summer weed growth can suddenly accelerate. If drone inspections are conducted regularly under similar conditions, it becomes easier to compare past and present conditions. It becomes easier to identify changes such as an increase in puddles in places where no problems were visible before, grass at the edge of paths encroaching under panels, and exposed bare soil appearing on parts of slopes.

However, just because drone surveys can be completed quickly, it is not appropriate to make final judgments based solely on them. Areas that look abnormal in images may actually be differences in appearance caused by shadows or the shooting angle. Conversely, there are issues that are difficult to detect from images alone, such as loosened equipment, damage, corrosion, or the condition around cables. Therefore, it is realistic to use drone surveys not as a substitute for on-site inspections but as an entry point to make on-site verification more efficient.

For property management companies, what matters is not viewing the entire site quickly but carrying out the necessary checks without omission. By using drone surveys to organize wide-area conditions and creating a workflow that confirms details through ground inspections, it becomes easier to reduce variation in inspection quality while improving the efficiency of patrol operations.

Benefit 2: Inspection records are easy to retain as objective data

In solar power plant management, it is important to record when, where, and in what condition something was checked. Relying only on verbal reports or brief notes can make it difficult to judge the situation when reviewing it later. Especially at sites where multiple personnel are involved, even the phrase "no issues" can mean different things to different people — how thoroughly something was checked and what level of condition was deemed acceptable may vary.

Drone surveying makes it easy to retain records containing images and location information, which makes it easier to explain inspection results objectively. If aerial overview images of the entire power plant, the condition of each section, the state of the perimeter, and the appearance of drainage routes are stored, it will be easier to grasp on-site conditions when reviewing them later. Attaching images to periodic inspection reports makes them useful not only for internal sharing within the management company but also for ensuring a shared understanding with power plant operators, construction companies, and maintenance partners.

When keeping records, it's important not only to save images but to organize them together with the date of capture, coverage area, purpose of inspection, weather conditions, whether any anomalies were observed, and the results of on-site verification. Even for the same power plant, the appearance can change depending on capture altitude and angle, time of day, and weather. To make an accurate comparison with previous data, it is desirable to keep the capture conditions as consistent as possible.

For example, when comparing before and after weed removal, photographing the same area from approximately the same position and angle makes it easier to verify the effectiveness of the work. When checking for poor drainage, recording conditions separately for immediately after heavy rain and for normal conditions makes it easier to explain where water tends to collect. When checking changes in slopes and developed areas, keeping records at regular intervals provides material to help determine whether the changes are temporary or are progressing continuously.

For property management companies, objective records also help prevent problems. When a drop in power generation or issues around equipment occur, being able to check past on-site conditions makes it easier to trace when the changes first appeared. Clogged drainage, overgrowth of grass, sediment accumulation, and deterioration of access paths often progress in stages rather than happening suddenly. If past photographic records exist, the likelihood of noticing changes at an early stage increases.

Also, drone survey records remain valid even when personnel change. Because past site conditions can be confirmed with images without relying on the predecessor’s experience or memory, it becomes easier to improve the accuracy of handovers. At solar power plants, where long-term operation is assumed, continuity of records is directly linked to management quality. Drone surveying can be utilized as a means to support the continuous creation of those records.

Benefit 3: Easier to detect signs of poor drainage and terrain changes

In solar power plants, drainage planning and terrain conditions are closely related to maintenance. If rainwater does not flow properly and concentrates in certain locations, it can lead to muddy access paths, slope erosion, sediment runoff, clogged drainage channels, and deterioration around racking foundations. Unlike failures of power generation equipment, these changes are hard to notice in the early stages, so it is important for the management company to identify them early.

Using drone surveying makes it easier to assess patterns of water flow and terrain tendencies across an area that are difficult to discern from the ground. From above, you can more readily identify where water is collecting in low-lying spots, traces of sediment movement, discoloration along drainage routes, differences in vegetation growth, and surface deterioration of pathways. Especially when images are captured after heavy rain, they provide clues to locations where puddles tend to persist and where drainage is likely to be impeded.

Ground patrols tend to result in spot checks. The person in charge can closely inspect the conditions where they walked, but it’s not easy to grasp the overall water flow across the entire site on the spot. Even if sediment has accumulated in part of a drainage channel, it can be difficult to determine whether that’s due to inflow from upstream or the surrounding grading without looking over a wide area. With aerial overview information from drone surveying, you can check not only the problem area but also the surrounding terrain and water flow together.

Also, by regularly recording data, it becomes easier to detect signs of terrain change. For example, changes such as vegetation thinning on part of a slope, rainwater flow paths becoming more pronounced than before, or increased sediment accumulation beside pathways are difficult to judge from a single inspection. By comparing with past records, it becomes easier to determine whether the change is progressing or merely a temporary seasonal variation.

However, you should avoid concluding that there are drainage issues or that the ground is unsafe based solely on drone images. What can be determined from images are only the signs that have appeared on the surface. To assess actual drainage capacity, ground conditions, and the impact on structures, on-site inspection and specialized surveys may be necessary. As a management company, it is appropriate to use drone surveys with the aim of quickly identifying suspicious areas and to link to detailed verification as needed.

Poor drainage and changes in terrain, if left unaddressed, can expand the area requiring restoration and increase maintenance costs and operational risks. By detecting signs early and linking them to small-scale cleaning, sediment removal, reviewing drainage routes, and establishing targeted patrols, a management company can strengthen its capacity to respond. Drone surveying is a means well suited to this preventive maintenance approach.

Benefit 4 Easy to assess the impact of weeds and nearby obstacles

In the operation and maintenance of solar power plants, addressing weeds and surrounding obstructions is also important. When weeds grow, they can cause shading of panels, reduced accessibility of inspection walkways, impaired visibility around fences, increased risk of wildlife intrusion, and clogging of drainage channels. Especially from spring to summer, growth is rapid, and even locations that had no issues at the previous inspection can become a condition requiring management in a short period.

Using drone surveying makes it easier to check the extent of weed growth from a broader perspective. During ground patrols you can assess grass height immediately in front of you and conditions around walkways, but it takes time to closely inspect everything—such as the far side of panel rows, the outer perimeter, slopes, and areas around retention ponds. Capturing images from the air makes it easier to identify sections where weeds are dense, the extent to which weeds have grown under panels, spots where paths are being blocked, and locations along fences that require management.

What’s important in weed management is not to judge it solely by its impact on power generation. Of course, shading on the panel surface affects generation efficiency, so care is necessary, but in the practical operations of management companies, the ease of inspection work and safety are also important. If grass grows too tall, changes in walkway levels or muddy patches can become hard to see, increasing the risk of trips and falls during patrols. When grass is densely clustered around equipment, it can also hinder visual inspections.

Also, depending on the surrounding environment of a power plant, tree growth and changes to adjacent land should also be monitored. Changes such as trees outside the site growing and casting shadows, soil or leaf litter washing in from surrounding areas, or sightlines around the perimeter fence becoming obstructed can be difficult to grasp as a whole from ground-level observations alone.

Using aerial overview images from drone surveys makes it easier to confirm the relationship between on-site and off-site areas.

It can also help when revising weed control plans. Rather than weeding all plots at the same frequency, prioritize managing areas where weeds are likely to grow, places prone to shading, around drains, along inspection paths, and near fences to more effectively reduce wasted work. If you record the extent of growth with drone surveys, it becomes easier to perform before-and-after comparisons of weeding work and to use the records to explain the scope of the work.

However, when confirming the effects of weeds and shadows, attention must be paid to the time of day when images were captured. Because the way shadows appear changes with the position of the sun, you should avoid concluding from images alone that a shadow’s effect is permanent. If there are areas of concern, it is important to increase the information available for management decisions by conducting on-site checks or rechecking at different times of day. Drone surveying is an effective supplementary means to broadly understand the condition of weeds and obstacles and to link that understanding to on-site responses.

Benefit 5: Easier to review maintenance plans and priorities

For companies that manage solar power plants, the accuracy of maintenance plans is directly linked to operational quality. With limited personnel and time, it is not realistic to inspect every area with the same frequency. Therefore, it is necessary to organize, based on the condition of the plant, which locations should be inspected intensively, which should be checked regularly, and which should be checked in the event of an anomaly.

Using drone surveying makes it easier to reassess priorities in maintenance planning. For example, based on imagery and topographic data you can identify and categorize low-lying areas prone to poor drainage, outer peripheral zones where grass tends to grow, the lower parts of slopes where sediment is likely to flow in, sections where paths show noticeable deterioration, and places around equipment where water tends to accumulate. This makes it easier to adjust patrol routes and inspection frequency to match actual field conditions.

In conventional maintenance plans, work is often carried out within the framework of regular inspections such as monthly, quarterly, and annual checks. Of course regular inspections are important, but the way risks emerge differs for each power plant. Even plants of the same scale require attention to different points depending on whether they are on flat or sloped terrain, whether there are many trees nearby, whether drainage systems are functioning adequately, and whether they are susceptible to heavy snowfall or heavy rainfall.

By regularly recording site conditions with drone surveying, maintenance plans can be shifted from uniform approaches to ones tailored to actual site conditions. After heavy rain, focus on checking drainage routes and slopes; before summer, check the extent of weed growth; after typhoons, check the perimeter fence and for any debris or blown-in objects; and if there is a long-term shutdown or a drop in power generation, also check for changes in shading and the surrounding environment. This makes it easier to put together such operational procedures.

Also, for companies that manage multiple solar power plants, it helps with comparisons between sites. By recording the condition of each plant in a consistent format, it becomes easier to determine which plant requires priority attention. If headquarters can verify the situation not only from reports by on-site personnel but also from images and survey data, deciding on a response policy will be smoother.

When reviewing a maintenance plan, it is important not to treat drone survey results in isolation but to combine them with power generation trends, past fault history, inspection records, weather conditions, vegetation control history, repair history, and so on. Even if no major issues are visible in the images, a detailed inspection is necessary if there are anomalies in power output or equipment condition. Conversely, even if changes are visible in the images, large-scale construction is not necessarily required immediately. You should cross-check multiple sources of information and make decisions after on-site verification.

The value of drone surveying is not just that it makes inspection work easier. It lies in making maintenance plans more realistic, clarifying response priorities, and increasing the evidence management companies can use to explain their decisions. By reducing discrepancies between plans and the field, it lessens the burden of ad-hoc responses and makes it easier to establish a stable management system.

Benefit 6: Easy to prepare explanatory materials for stakeholders

In the management of solar power plants, there are situations where information must be shared not only with on-site personnel but also with multiple stakeholders such as power generators, landowners, construction companies, maintenance partner companies, and internal management departments. To accurately convey changes occurring at the site, reports consisting only of text may be insufficient. In particular, issues such as poor drainage, sediment inflow, overgrown weeds, slope deformation, and abnormalities around the perimeter are easier to explain with photos or diagrams.

Aerial images obtained from drone surveys have the advantage of being easy to use as explanatory materials for stakeholders. They make it easier to show where a problem is occurring within the entire power plant, what area is affected, and the positional relationships with surrounding equipment. Even when it is difficult to identify a location using only ground-based photos, combining them with aerial images makes it easier for stakeholders to share the same understanding.

For example, when reporting that sediment has accumulated in a drain, ground-level photos alone can make it difficult to convey where the sediment came from and how widely it is affecting the area. Showing the surrounding topography and water flow with drone images makes it easier to discuss whether cleaning alone is sufficient or whether the drainage route needs to be revised. The same applies to weed control: indicating the extent of overgrowth from above makes it easier to explain the scope of work and priorities.

When explaining to stakeholders, comparison with the past is also important. By placing images from the previous inspection and the current inspection side by side, it becomes easier to intuitively understand whether any changes have occurred. Changes such as the exposed slope surface widening, increased sediment beside walkways, or taller grass around fences are better shown with images than described in words alone, as this helps prevent misunderstandings.

Additionally, it can be used for completion reports after performing repairs or vegetation control. By keeping before-and-after images of the work, it becomes easier to explain which areas were addressed and what condition they are in afterward. At remote power plants, operators and management departments may not be able to visit the site frequently. In such cases, records from drone surveys serve as effective material for sharing on-site conditions.

However, when using it as explanatory material, both clarity and accuracy are required. When marking images, it is important to clearly identify the target locations and to separate conjectures from confirmed findings. If you do not distinguish whether a condition was judged to be a possible anomaly based on the image or was actually confirmed by on-site inspection, you may cause misunderstandings among stakeholders.

As a management company, producing highly reliable reports requires not simply showing drone survey results as-is, but organizing what was checked, what was determined, and what remains unverified. By combining aerial images, ground photographs, inspection notes, and response history, you can create explanatory materials that are practical and easy to use in day-to-day operations.

Considerations When Introducing Drone Surveying

When incorporating drone surveying into the management of a solar power plant, it is necessary to understand not only the benefits but also the precautions. First and foremost, it is important to check the laws and regulations on flights, local rules, and any constraints related to facility management. Depending on the plant’s location and surrounding environment, there may be restrictions on flight methods and flight range. It is essential to carry out the necessary checks in advance and develop a plan that prioritizes safety.

Next, attention to the safety of power generation equipment is required. Solar power plants include panels, mounting racks, electrical equipment, cables, fences, monitoring devices, and so on. If a drone approaches equipment too closely during flight, the risk of contact or crash increases. On days with strong winds, in rainy conditions, or when visibility is poor, it may be necessary to decide not to fly. Even if the purpose is surveying or filming, safety must not be sacrificed.

Also, it is important to decide the imaging plan in advance. If it is unclear which area will be imaged, at what heights and angles inspections will be made, when it will be conducted, or what criteria will be used for evaluation, the resulting data can become difficult to use. By clarifying the purpose—such as an overall aerial inspection of the power plant, checking drainage routes, assessing weed overgrowth, monitoring slope changes, or comparing conditions before and after construction—before implementation, it becomes easier to incorporate the results into maintenance plans.

Rules for data management are also important. Photographs and survey data should be organized so that the power plant name, date of capture, area captured, person in charge, and purpose of verification are identifiable. If storage locations and file-naming conventions are not standardized, it can take time to find required data later. When managing multiple power plants, it is preferable to record using the same rules for each plant.

Furthermore, it is necessary to organize how to interpret the information obtained from drone surveys. If a possible anomaly is found in an image, criteria are needed to decide whether to carry out immediate repairs, conduct an on-site inspection, or recheck at the next inspection. Simply increasing the number of images without such criteria is unlikely to lead to improvements in management operations. Drone surveying is a means of increasing the information available for maintenance decisions, and final judgments may require on-site confirmation or specialist evaluation.

Establishing an internal organizational structure is also indispensable. Even when outsourcing drone surveying, if the management company does not clearly communicate the objectives and the required deliverables, the data provided may not meet practical needs. Conversely, when operating in-house, it is important to clarify roles such as the flight operator, the person responsible for data verification, the person who prepares reports, and the person who incorporates the results into maintenance plans.

When introducing the system, rather than starting the same operation at all power plants at once, you can pilot the operation at plants that have many management challenges or are easy to compare. Verify effectiveness at sites prone to poor drainage, sites where weed control is labor-intensive, or large sites that take a long time to patrol, and use those results to establish operating rules so the practice can be adopted smoothly.

Summary

For companies managing solar power plants, drone surveying is an effective means of grasping the overall condition of a plant and reviewing maintenance plans. It makes it easy to inspect large sites in a short time and to retain inspection records as objective data, which leads to greater efficiency in daily management. It also makes it easier to detect signs of poor drainage, terrain changes, and the effects of weeds or surrounding obstacles, providing an opportunity to notice changes that are easy to overlook with on-site patrols alone.

Furthermore, images and data obtained from drone surveys provide material for revising maintenance plan priorities. They make it easier to determine which sections should be inspected intensively, when to perform weeding or drainage checks, and at which power plants early action is required. They are also easy to use as explanatory materials for stakeholders and help align understanding with power plant operators and maintenance partners.

On the other hand, drone surveying is not a panacea. Avoid drawing definitive conclusions about equipment anomalies or ground conditions from images alone; it is important to combine drone data with on-site inspections and specialist investigations as needed. By implementing and using established flight rules, safety management, imaging plans, data organization, and decision criteria, it can become a management tool that is useful in practical operations.

In managing solar power plants, it is important not to respond only after abnormalities have grown large, but to detect small changes early and respond in a planned manner. Drone surveying can be used as a technology to support this preventive maintenance approach. Management companies that want to reduce the burden of on-site patrols while improving the quality of records and raising the accuracy of maintenance plans should consider how to utilize drone surveying in ways that suit their management systems and the conditions of their power plants.