7 Maintenance Tips to Increase Power Output | Explaining the Risks of Neglect

Table of Contents

• Maintenance to increase power generation starts with identifying power losses

• Maintenance 1: Regularly check power generation data to detect signs of decline

• Maintenance 2: Manage dirt and deposits on panel surfaces

• Maintenance 3: Minimize shading from weeds, trees, and surrounding structures

• Maintenance 4: Inspect connections, cables, and strings for abnormalities

• Maintenance 5: Review shutdowns, curtailments, and the thermal environment of power conversion equipment

• Maintenance 6: Maintain drainage, terrain, and access routes to prevent recurrence

• Maintenance 7: Keep inspection records and location information to continue improvements

• Risks of ignoring decreased power generation

• Summary

Maintenance to increase power generation starts with understanding generation losses

When you want to increase the electricity output of a solar power system, the first important step is not to add more equipment but to verify that the existing equipment is delivering its intended generation capacity. In solar power generation, you cannot increase the amount of solar irradiance on-site. However, you can move the system closer to a state in which the received irradiance is converted into electricity with as little waste as possible. In practical terms, maintenance aimed at increasing generation involves finding the causes of power that should be generated but is being lost, and taking measures to reduce those generation losses.

The causes of reduced power generation are not limited to a single factor. Dirt on the panel surface, deposits such as bird droppings and fallen leaves, shading from weeds or trees, faults at connection points, cable damage, abnormalities at the string level, stoppage of power conversion equipment, output curtailment, temperature increases, poor drainage, and site environments that are difficult to inspect — multiple factors can combine to lower generation. Even if there appears to be no major problem on the surface, when you check generation data by time of day or by equipment unit, you may find that only certain parts are showing a continuous decline.

For practitioners searching "how to increase power generation," the important thing is not to judge solely by the fact that generation is low. Where you should look depends on whether it's only low in the morning, only low in the evening, the daytime peak isn't rising, it becomes unstable after rain, or only certain equipment is underperforming. Whether you should clean, remove weeds, inspect connection points, check equipment history, or even review drainage and terrain needs to be determined by combining the data with on-site conditions.

Also, maintenance is not something you do once and then finish. Even if you clean, dirt will return; even if you weed, grass will grow back; trees will grow; and equipment and wiring will change condition with age. Drainage routes also change due to sediment and fallen leaves, and inspection paths are affected by the seasons and weather. Therefore, increasing power generation requires a management approach that repeatedly performs status checks, isolates causes, implements countermeasures, verifies their effectiveness, and updates records. From here on, I will explain seven maintenance tasks that should be prioritized in practice to increase power generation.

Maintenance 1: Regularly check power generation data to detect signs of decline

The first step in maintenance to increase power generation is to regularly check power generation data. Rather than going to the site first and then searching for causes, start by using the data to understand "when", "where", and "how" the output is declining. If you only look at monthly or annual generation, you cannot tell the timing of generation losses or differences at the equipment level. Even if nothing looks like a major anomaly on a monthly basis, there may be cases where output falls only during certain hours on sunny days, or where only specific equipment continues to underperform.

Checking by time of day makes it easier to identify the likely direction of the cause. If generation in the morning is low, shadows from trees on the east side, slopes, surrounding structures, or adjacent equipment may be involved. If it is low in the evening, check for shadows on the west side and the influence of surrounding terrain. If the midday peak does not develop, candidates include dirt on the panel surface, temperature rise, limits of power conversion equipment, output curtailment, and equipment shutdowns. If the generation curve suddenly drops during a sunny day, you need to correlate the time with shutdown logs and alarm histories.

Comparison on a per-equipment basis is also indispensable. If you only look at the power generation of the entire plant, some abnormalities can be obscured by the average. Compare installations with the same orientation, the same tilt, a similar number of panels, and the same shading conditions, and check whether only certain rows or strings are consistently lower. If only a part is lower compared with equipment under similar conditions, localized soiling, partial shading, poor connections, cable damage, or malfunctions in equipment may be suspected.

If data checks are neglected, noticing a decrease in power generation will be delayed. Short-term stoppages or partial equipment degradation may not stand out in the monthly totals. However, if stoppages or drops occur during periods of strong sunlight, the generation losses become large. To increase power generation, it is important to detect small differences at an early stage rather than respond only after abnormalities become pronounced. Regular data checks are basic maintenance that should be carried out before cleaning or repairs.

Maintenance 2: Managing Dirt and Deposits on Panel Surfaces

Surface dirt and deposits on panels are a common cause of reduced power generation. Because solar panels generate electricity by receiving sunlight on their surface, when dirt adheres the light reaching the cells is reduced. The way panels become soiled varies with site conditions and includes soil dust, pollen, yellow sand (Asian dust), bird droppings, fallen leaves, sap, dust from nearby construction, road-derived dust, and salt-containing deposits that tend to accumulate near the coast. Even light soiling can affect power generation if it spreads over a wide area, and localized deposits can act as strong shading even over a small area.

Particular attention should be paid to the band-like dirt that remains on the lower edge of panels and around the frame. It is often assumed that rain will naturally wash it away, but in reality the flow of rainwater can gather dirt at the lower edge and leave it there. On panels with a shallow slope, water does not drain well and dirt tends to accumulate. Even dirt that is not noticeable from a distance can affect power generation if it covers part of a cell. During maintenance, it is necessary to carefully check not only the overall color of the panel but also the lower edge, corners, and the area around the frame.

Localized deposits such as bird droppings and fallen leaves should not be overlooked. Unlike dirt that spreads thinly across the entire surface, these cover specific spots more heavily and create partial shading. If only some installations show reduced power output, focus inspections on the panel surfaces around those installations. Rows near trees, areas around structures where birds tend to perch, rows that are prone to being downwind, and locations near unpaved pathways are more susceptible to dirt and deposits.

When performing cleaning, it is practical to prioritize areas that have the greatest impact on power generation. Rather than cleaning all panels with the same frequency, focus on equipment where a drop in power generation has been confirmed, rows with concentrated soiling, areas where soiling is particularly noticeable at the lower edges, and locations with heavy bird damage or fallen leaves. Comparing photos and power generation before and after cleaning makes it easier to determine how much the soiling at that site affected generation.

Cleaning should be performed in a way that does not damage the equipment. Avoid vigorously scrubbing with hard tools, carrying out sudden work during times when the panels are at high temperature, or working without having performed electrical safety checks. Cleaning to increase power generation is not merely a cosmetic task; it is maintenance to restore the light-receiving condition and to keep the equipment in use stably for a long time. If dirt is left unaddressed, not only will generation losses continue, but deposits will repeatedly build up in the same locations, making it more likely that changes in condition will be overlooked during inspections.

Maintenance 3: Minimizing Shadows from Weeds, Trees, and Nearby Structures

Shadow management is essential in maintenance to increase power generation. Because solar panels generate electricity from sunlight, even a shadow over part of a panel can reduce power output. Causes of shadows include weeds, trees, fences, utility poles, nearby buildings, mounting structures, adjacent rows of panels, monitoring equipment, and other factors. Shadows move with the time of day and season, so the fact that a shadow wasn't visible at the time of inspection does not necessarily mean there is no problem.

Weeds are a common cause of power generation losses on-site. Even if they are not a problem in winter or immediately after installation, they can grow rapidly from spring to summer and cast shadows on the lower edges of panels and on the front rows. Even if the vegetation does not touch the panels, shadows lengthen with the low solar altitude in the morning and evening. Furthermore, when weeds proliferate, ventilation worsens, inspection walkways become blocked, and it becomes difficult to check around equipment. Because they affect not only power output but also maintainability and safety, weed management is fundamental to improving generation.

Tree shadows are a factor that tend to become problematic during long-term operation. Even trees that had little impact at the time of installation can grow over several years and reduce power generation. Trees located on the south, east, and west sides in particular cast shadows on panels depending on the time of day. At power plants near forests or slopes, the elevation of the terrain combined with tree height can create long shadows in winter. If generation is low only in winter, or there are large drops in the morning and evening, it is necessary to check both the trees and the terrain together.

When checking shadows, aligning power generation data with the times of on-site inspections makes it easier to find the cause. If generation is low in the morning, check the on-site conditions in the morning; if it is low in the evening, look at the evening shadows. Even if there is no problem at noon, large shadows can appear in the morning or evening. Also, even if there is no problem in summer, shadows can lengthen in seasons when the sun is lower in the sky. Shadows should be treated not as a single point in time but as something that changes with time and season.

Neglecting weed control and pruning not only reduces power generation but also leads to delayed inspections and deterioration of the environment around equipment. If pathways are blocked by grass, it takes longer to reach abnormal areas. When grass around equipment grows, ventilation can worsen and heat can become trapped. To increase power generation, it is important to manage weeds and trees not just for appearance but also for factors that affect generation—shading, inspection access routes, and ventilation around equipment.

Maintenance 4: Inspect connections, cables, and strings for abnormalities

To increase power output, you need to check not only the panel surface and shading but also the electrical pathways that extract the power. Even if a solar panel is receiving sunlight normally, faults in connections or cables can prevent the generated electricity from being fully extracted. Differences in generation at the string level, loose terminals, poor contacts, damaged cable insulation, moisture ingress, damage caused by animals, damage during grass-cutting operations, and deterioration due to aging are all significant causes of reduced power output.

When checking for anomalies at the string level, the basic rule is to compare units under the same conditions. If you simply compare systems that differ in panel count, orientation, tilt, shading conditions, or connection configuration, you may mistakenly interpret normal differences as abnormalities. Compare with adjacent rows or installations with the same orientation to see if any are consistently lower. If only a specific string is lower, possible causes include panel soiling, partial shading, poor connections, cable damage, or equipment-side problems.

Pay attention to how the anomaly appears. If it is consistently lower than the surroundings even on sunny days, dirt or connection problems are suspected. If it is lower only in the morning and evening, check for shading effects. If anomalies tend to appear after rain, moisture ingress or the condition of the connections may be involved. If it becomes unstable during periods of high temperature, poor contact or the temperature environment around the equipment are also possible causes. Combining the power generation waveform with on-site conditions makes it easier to narrow down the cause.

Inspections of electrical equipment must be carried out with safety as the top priority. Rather than having on-site personnel forcefully touch equipment and make judgments, it is important to organize which equipment is showing abnormalities, the time of occurrence, changes in power output, on-site photos, and the surrounding environment, and to connect to professional inspections as needed. If defects in connection points or cables are left unaddressed, not only will power output continue to decline, but risks affecting the safety of the equipment will also increase.

Also, faults in connection points and cables may be related to the surrounding environment. In areas with many weeds, it becomes difficult to check the condition of cables. There is also a possibility that cables may be contacted during grass-cutting operations. In locations with poor drainage, moisture and standing water can affect the connection points. At power plants where animals can easily enter, cable damage can also occur. For maintenance aimed at increasing power generation, it is important to check electrical faults together with the site environment rather than treating them separately.

Maintenance 5: Review shutdown, suppression, and temperature environment of conversion equipment

The causes of low power generation are not limited to the panels and wiring. If the equipment that converts the generated electricity is stopped or its output is being limited, generation will not increase even when solar irradiance is sufficient. In maintenance aimed at raising power output, it is essential to check the operating status of the conversion equipment, shutdown history, alarm history, and whether output curtailment is in effect.

When reviewing downtime history, confirm which equipment stopped, when, and for how long. Even short interruptions can cause large losses if they occur during the daytime when power generation is high. If stops and restarts are repeatedly occurring during the day, they may not be noticeable in the monthly total but can still mean you are losing generated power. Whether only specific equipment stops or multiple pieces of equipment stop simultaneously will change the suspected causes.

If output curtailment is occurring, power generation can plateau even on sunny days. If the top of the generation curve looks flat, check the operating information and history. However, a flat curve does not necessarily mean output is being curtailed. Similar shapes can result from equipment capacity limits, temperature rise, soiling, shading, or measurement anomalies. Do not judge based solely on the generation curve; it is important to verify by comparing equipment logs and on-site conditions.

The surrounding environment of conversion equipment is also important. Conditions such as weeds growing around the equipment, poor ventilation, excessive dust or deposits, and a tendency for heat to build up can affect operating efficiency and the risk of shutdown. Even if the equipment itself shows no abnormalities, a poor surrounding environment can hinder stable operation. It is important to keep the area around the equipment in a state that is easy to inspect, allows airflow, and enables immediate confirmation if any abnormalities occur.

Solar power generation tends to produce more electricity the stronger the solar irradiance, but higher temperatures can sometimes limit output increases. If on a sunny summer day the generation does not increase as expected, check not only the irradiance but also the panel temperature and the temperature around the equipment. If weeds are growing under the panels, there is grass or obstacles around the equipment, or dust and deposits are hindering heat dissipation, these can affect the increase in power generation. Leaving these conditions unaddressed can not only lead to continued reductions in generation but also make detection of stoppages or abnormalities more likely to be delayed.

Maintenance 6: Improve Drainage, Topography, and Pathways to Prevent Recurrence

Maintenance to increase power generation must consider not only the panels and equipment but also the power plant’s overall drainage, terrain, and inspection walkways. Areas where water tends to accumulate, spots where sediment flows in, pathways prone to becoming muddy, slope failures, scouring around mounting structures, and locations where cables are likely to become exposed can directly or indirectly cause decreases in power generation. Poor drainage and changes in terrain may seem unrelated to power generation at first glance, but they are important factors that lead to soiling, weed growth, faults at connection points, and reduced accessibility for inspection.

Areas where puddles remain after rain are prone to rapid weed growth. When weeds grow they create shading, reduce ventilation, and make inspections more difficult. Muddy paths slow down work, and cleaning and weeding may be carried out less frequently. In locations where sediment washes in, it can accumulate under panels and around cables, causing soiling and damage. If the same spots get dirty again soon after cleaning, drainage or terrain problems should be suspected.

When checking terrain and drainage, on-site inspections after rain as well as during fine weather are effective. Identify where water flows in, where it pools, and where it drains out. Recording puddles, sediment deposits, vegetation overgrowth, pathway subsidence, and slope changes will reveal locations prone to recurrence. If poor drainage is left unaddressed, soiling and weeds will recur, resulting in the same power generation losses occurring repeatedly.

Securing access for inspections is also important. Locations that are difficult to inspect tend to delay the detection of abnormalities. If grass has overgrown so you cannot pass, if it is too muddy to approach, if equipment identification numbers are hard to read, or if it is difficult to share information about abnormal locations, on-site response will take longer. Even if you find underperforming equipment in the data, improvements will be delayed if it takes time to reach the relevant site.

Maintenance of drainage, terrain, and access routes may not immediately appear as an increase in power output when carried out. However, in the long term it helps reduce dirt, weeds, poor connections, and delayed inspections. To stably increase power output, it is necessary not only to maintain the power generation equipment itself but also to organize the power plant into an environment that is easy to manage. If left unattended, the site becomes difficult to work in, and both the detection of and response to abnormalities are likely to be delayed.

Maintenance 7: Retain inspection records and location information to continue improvements

To continue maintenance aimed at increasing power generation, keeping inspection records is essential. Even if dirt, shading, anomalies, or drainage problems are found on site, if the exact location is not shared, remediation and rechecks will take time. In particularly large power plants, rows and equipment can look similar, so photos alone may make locations hard to identify. By managing inspection results linked with location information, the practical work of improving power generation can be greatly streamlined.

What you should record are the locations of equipment with low power output, rows that are prone to soiling, places where shadows occur, areas where water accumulates, spots where connection failures occurred, locations that were repaired, and the areas where cleaning or weeding was carried out. Leaving photos, the date and time, equipment numbers, work performed, details of any abnormalities, the status of responses, and the need for reinspection will be useful for the next inspection. If you add too many items to the records they will not be maintained in the field, so it is important to start by making sure that, when viewed later, it is clear "where and what happened."

Linking power generation data with on-site photographs makes it easier to determine causes. If the locations of low-performing installations coincide with areas where shadows occur or drainage is poor, the rationale for countermeasures becomes clear. If the power output at a cleaned location improves, you can conclude that soiling had a significant impact at that site. If morning and evening power output improves after weeding, it is likely that shadowing from weeds was the cause. Having records speeds up decision-making in future cases.

If insufficient record-keeping is left unaddressed, the same problems will recur. Even if there are patterns—grass grows in the same places every year, dirt accumulates in the same rows, the same walkways become muddy after rain, and the same equipment experiences shutdowns—without records the next response will be ad hoc. To increase power generation, inspections should not be treated as mere checks; they should be recorded and stored as information that can be used for future improvements.

When multiple people are responsible for management, being able to share the exact same location is important. If you record the equipment number, location information, and photos together, on-site personnel, managers, inspection staff, and repair personnel can more easily confirm the same location. Improving power output is not only about noticing issues on-site but also about keeping that information in a form that stakeholders can share. By continuing to manage records, you can move closer to maintenance that prevents drops in power output.

Risks of Ignoring Declines in Power Generation

The greatest risk of leaving a decline in power generation unaddressed is that generation losses accumulate day by day. Even if the daily drop appears small, if it continues for weeks, months, or years, the amount of lost generation becomes substantial. In particular, soiling, shading, string-level abnormalities, and short-term equipment outages can be difficult to notice in monthly totals. If such hard-to-detect declines are left unaddressed, identifying the cause will be delayed and opportunities for improvement will be missed.

Leaving dirt and deposits unattended reduces the amount of light the panels receive. When dirt continues to build up along the lower edge of a panel, or bird droppings and fallen leaves remain, they act as partial shading and impede power generation. If shadows from weeds and trees are left unaddressed, the shaded area can expand as the season progresses. Generation losses that were initially limited to certain times of day may become prolonged as grass grows and trees lengthen.

Avoid leaving abnormalities in connection points or cables unaddressed. Not only can power output decline, but the risk to the safety of the installation may increase. If you notice signs such as instability after rain, lower output in only certain strings, or a sudden drop in the power generation curve, you should identify the cause promptly. Even if the reduction in power output appears minor, careful handling is required if an electrical fault is underlying.

If poor drainage and worsening inspection access are left unaddressed, maintenance itself will be delayed. When puddles, mud, sediment buildup, or overgrown vegetation make on-site inspections difficult, both anomaly detection and repairs are delayed. At sites that are hard to work in, cleaning and weeding tend to be carried out less frequently, and as a result power generation losses recur. To increase power output, it is important not to respond after problems have grown, but to detect the early signs of power generation loss through routine maintenance.

Summary

When performing maintenance to increase power output, it is important to consider cleaning, weed control, inspection, repairs, and record-keeping as an integrated whole. In solar power generation, you cannot increase the amount of solar irradiance itself on site. However, by bringing the system closer to a condition that converts received solar irradiance into electricity without waste, you can reduce generation losses. To do this, you need to check power generation data and then, in order, review soiling, shading, connection points, cables, power conversion equipment, drainage, and inspection records.

When you notice low power output, instead of immediately considering major renovations, it is important to first break down and examine the data. Check when output is low, which equipment is underperforming, and whether there are differences compared with equipment under the same conditions. Then, by inspecting the site you will clarify where cleaning is needed, which areas require weed removal, which connection points need inspection, which devices should be checked, and which drainage and access routes should be reviewed. To maximize maintenance effectiveness, it is important to make decisions based on data and on-site conditions rather than on intuition.

Also, if drops in power generation are left unaddressed, small losses accumulate. Dirt and shadows gradually spread, and the longer faults in connections and cables go undetected, the greater their impact. If drainage problems or walkway issues are left unattended, inspections and cleaning themselves are delayed. To steadily increase power generation, it is essential not to treat countermeasures as a one‑time fix; you must check changes in power output after cleaning, after weeding, and after repairs, and use those findings to inform the next inspection.

In particularly large power plants, a mechanism for accurately sharing problem locations is important. If you record dirt-prone rows, locations where shadows occur, places where water accumulates, abnormal strings, repair locations, cleaning scope, and inspection photos along with location information, stakeholders can more easily confirm the same locations. By combining power generation data with on-site location information, it becomes easier to explain the priority of cleaning, weeding, and repairs, and it also streamlines follow-up checks for recurrence.

If you want to continue maintenance to increase power generation based on on-site data, using LRTK is also effective. LRTK, as an iPhone-mounted GNSS high-precision positioning device, is useful for recording inspection locations within solar power plants, areas prone to soiling, locations where shadows occur, drainage-failure spots, abnormal equipment, repair locations, cleaning ranges, and on-site photographs together with high-precision positional information. By advancing power generation improvements with records that include positional information rather than by intuition, you can reduce the risk of leaving issues unaddressed and more easily sustain the effectiveness of maintenance.