Beginner's Guide to Increasing Power Generation｜6 Places Beginners Should Check

Table of Contents

• Increasing power generation begins with reducing generation losses

• Where to look 1: Power generation data and generation curves

• Where to look 2: Dirt and deposits on panel surfaces

• Where to look 3: Shadows from weeds, trees, and surrounding structures

• Where to look 4: Abnormalities in connections, cables, and strings

• Where to look 5: Power conversion equipment and the surrounding environment

• Where to look 6: Drainage, terrain, and ease of inspection

• Record keeping for beginners to continue improving power generation

• Summary

Increasing Power Generation Starts with Reducing Generation Losses

When thinking about increasing the power output of a solar power system, what beginners should first understand is that you cannot increase the amount of solar irradiance on site. Solar power generation converts the light received from the sun into electricity, so there will always be fluctuations caused by weather and season. However, you can move closer to a state where the light received is converted into electricity with as little waste as possible. In other words, in practical terms, increasing power generation is not only about adding equipment but also about reducing generation losses in the existing equipment.

The causes of low power generation cannot be pinned down to a single factor. Dirt on the panel surfaces, bird droppings and fallen leaves, shading from weeds or trees, faults at connection points, cable damage, shutdowns of conversion equipment, output curtailment, temperature increases, poor drainage, site conditions that make inspection difficult, and other various factors combine to reduce power output. It is difficult for a beginner to make all of these judgments expertly at once, but if you determine the places to check in order, it will be easier to isolate the cause.

When you feel that power generation output is not improving, it is important to first assess the overall situation. The suspected causes differ depending on whether the entire plant is underperforming, only certain equipment is low, output is low only in the morning, the midday peak is not rising, or it drops in the evening. If you look only at the result of low power output and immediately proceed with cleaning or repairs, the actual cause and the countermeasures may not align. Establishing a workflow of reviewing the data before inspecting the site is the first step to improving power generation.

Beginners should be careful not to judge too much by appearances. Even if panels appear to be aligned from a distance and show no major damage, there may be dirt accumulated along the lower edges, shadows that occur only in the morning and evening, or reduced power output affecting only specific strings. Conversely, what seems like low power output may simply be the result of many cloudy or rainy days and not indicate a significant problem with the equipment. When considering ways to increase power generation, it is necessary to look at a combination of weather, time of day, equipment-level data, and on-site conditions.

Improving power generation is not something that can be completed in a single operation. Even if you clean, dirt will accumulate again; even if you remove weeds, grass will grow; trees will grow; and drainage routes will change. Equipment and wiring also change condition over time. Therefore, to increase power generation, it is important not only to find problems but also to record the measures taken and apply them to the next inspection. This article explains six places beginners should check first, in the order that is easiest to verify in practice.

What to Check 1: Power Output Data and Power Curve

The first place beginners should look is not the site, but the power generation data. When you feel the generation is low, rather than rushing out to inspect the panels, first check the data to see "when", "where", and "how" it is low—this makes it easier to find the cause. Looking only at monthly or yearly generation can be heavily influenced by weather and may not allow you to accurately determine equipment abnormalities. What’s important is to look at generation by time of day and by individual equipment.

When generation is low in the morning, shadows from trees on the east side, slopes, surrounding structures, or adjacent equipment may be involved. When generation is low in the evening, check for shadows on the west side and the effects of surrounding terrain. If the midday peak does not develop, possible causes include dirt on the panel surface, temperature rise, limitations of power conversion equipment, output curtailment, or equipment shutdowns. If there is a sudden drop in the generation curve even on clear days, it is necessary to correlate the times with equipment shutdown logs and alarm histories.

When reviewing power generation curves, it is important to choose a sunny day whenever possible. On cloudy or rainy days, output fluctuates greatly due to moving clouds, making it difficult to distinguish from equipment anomalies. On sunny days, the shape of the generation curve is relatively stable, so features such as shading, shutdowns, output curtailment, and string faults are easier to identify. Even beginners can more easily spot areas that are abnormally low by comparing similar equipment within the same power plant.

When comparing equipment on a per-unit basis, it is important to look at equipment under the same conditions. If you simply compare equipment with different orientation, tilt, number of panels, shading conditions, or connection configurations, you may mistakenly judge a normal difference as an anomaly. If only part of a system is consistently lower compared with adjacent rows or equipment with the same orientation, it is likely that the cause is on-site. Suspect dirt, shading, poor connections, cable damage, or equipment-side faults, and prioritize on-site inspection.

Declines in power generation can be either sudden or gradual. Sudden drops may be related to equipment shutdowns, wire breaks, poor connections, or the emergence of obstructions. Gradual declines may be associated with accumulation of dirt, the growth of weeds or trees, aging of equipment, or environmental deterioration caused by poor drainage. Even by looking at power generation data alone, you can see what should be prioritized for on-site inspection.

Developing a habit of checking power generation data can reduce unnecessary inspections. Rather than wandering aimlessly around the entire plant, if output is low in the morning check for morning shadows; if it doesn’t rise at midday check for dirt or equipment issues; if it’s low in the evening focus on shadows on the west side. For beginners, looking at the data may seem difficult, but it is the most basic check when considering how to increase power generation.

What to Check 2: Dirt and Deposits on the Panel Surface

The next place to check is the surface of the solar panels. Because panels generate electricity by receiving sunlight at their surface, dirt and deposits reduce the light reaching the cells and decrease power output. The way panels get dirty varies with the site environment, such as soil dust, pollen, yellow sand, bird droppings, fallen leaves, sap, dust from nearby construction, dust from roads, and salt-containing dirt that easily adheres in coastal areas. Even beginners can relatively easily check the condition of the panel surface.

Particular attention should be paid to band-like stains that remain on the panel's bottom edge and near the frame. It is often assumed that rain will naturally wash away dirt, but in reality the flow of rainwater can cause dirt to collect at the lower edge and remain there. On panels with a shallow tilt, water does not drain easily 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.

Deposits such as bird droppings or fallen leaves should not be overlooked. Unlike dirt that spreads thinly across an entire surface, these cover specific spots densely and therefore act as partial shading. If only some installations have reduced power generation, check the panel surfaces in those areas. Rows close to trees, around structures where birds tend to perch, rows that are often downwind, and areas near unpaved walkways tend to be more prone to dirt and deposits.

When cleaning, it is practical to prioritize areas that have the greatest impact on power generation. Rather than cleaning all panels at the same frequency, concentrate on installations where a drop in generation has been confirmed, rows where dirt is concentrated, areas where soiling is noticeable at the lower edge, and places with heavy bird activity or fallen leaves. Comparing photos and power output before and after cleaning makes it easier to determine how much the soiling affected power generation at that site.

However, cleaning must be carried out in a way that does not damage the equipment. Avoid vigorously scrubbing with hard tools, performing sudden work during periods when panels are at high temperature, and working without first confirming electrical safety. Cleaning to increase power generation is not a cosmetic task but a maintenance operation to restore light-receiving conditions and to keep the equipment in long-term, stable use.

For dirt-control measures, it's important not only to remove dirt but also to understand why it recurs. Check whether dust is likely to be kicked up from unpaved walkways, whether nearby trees tend to drop leaves or sap, whether there are spots that attract birds, or whether the panel angle prevents rainwater from draining properly. Understanding the causes will make it easier to decide the timing of the next inspection and the priority of cleaning.

Checkpoint 3: Shadows of weeds, trees, and surrounding structures

The next thing beginners should look at is anything casting shadows on the panels. In solar power generation, even a shadow on part of a panel can reduce power output. Causes of shadows include weeds, trees, fences, utility poles, nearby buildings, mounting racks, adjacent rows of panels, monitoring equipment, and so on. Because shadows move with the time of day and the seasons, not seeing a shadow at the time of inspection does not necessarily mean there is no problem.

Weeds are a cause of power generation loss that even beginners can easily notice. Even if there’s no 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 the front rows. Even if the vegetation doesn't touch the panels, shadows stretch long at the low solar elevation angles of morning and evening. Furthermore, when weeds become dense, ventilation worsens, inspection walkways become blocked, and it becomes harder to inspect around equipment. Because they affect not only power output but also maintainability and safety, weed management is fundamental to improving power generation.

Shading from trees is a factor that tends 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 to the south, east, and west in particular can cast shadows on panels at different times of day. At plants near forests or slopes, terrain elevation combined with tree height can create long shadows in winter. If power generation is low only during winter, or there are large drops in the morning and evening, it is necessary to check both trees and terrain together.

When checking shadows, it's easier to identify the cause if you align the power generation data with the times of on-site inspections. If generation is low in the morning, check the on-site conditions in the morning; if it's low in the evening, look at the shadows in the evening. Even if nothing is wrong when checked at noon, there may be large shadows in the morning or evening. Also, even if there is no problem in summer, shadows can lengthen in seasons with a lower solar altitude. Shadows should be viewed not as a single moment but as something that changes with time and season.

When performing weeding or pruning, prioritize the areas that have the greatest impact on power generation. Rather than aiming only to uniformly tidy the entire site, focus on the area in front of the panels, around equipment, inspection walkways, and the directions in which shadows are likely to extend. After the work, record whether shadows were actually eliminated, whether inspections have become easier, and whether airflow has improved. Because shadow problems tend to recur, management should not be treated as a one-time operation but should anticipate regrowth of grass and trees.

Shadows from nearby structures should not be overlooked. Adding new equipment within the power plant, or installing fences, signs, or surveillance poles can cast shadows at certain times of day. To increase power generation, it is important not only to reduce existing shadows but also to avoid creating new ones. Beginners should start by taking photos to record from which directions shadows fall and around what times they appear.

Inspection Point 4: Abnormalities in Connections, Cables, and Strings

To increase power output, you need to check not only the panel surface and shading but also the pathways that extract the electricity. It may feel a little difficult for beginners, but differences in generation at the string level, faults in connection points, and cable damage are important causes of reduced power output. Even if solar panels are receiving sunlight normally, problems in the connections or cables can prevent the generated electricity from being extracted sufficiently.

When checking for anomalies at the string level, the basic rule is to compare like-with-like. If you simply compare strings that differ in panel count, orientation (azimuth), tilt, shading conditions, or connection configuration, you may mistakenly interpret normal differences as abnormalities. Compare with adjacent rows or equipment with the same orientation to check whether any are consistently lower. If only a particular string is low, candidates 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 clear days, dirt or connection problems may be suspected. If it is lower only in the mornings and evenings, check for the effects of shading. If anomalies tend to appear after rain, moisture ingress or the condition of connection points may be involved. If it becomes unstable during high-temperature periods, poor contact or the thermal environment around the equipment are also possible causes. Combining the power output waveform with on-site conditions makes it easier to narrow down the cause.

Faults in connection points and cables can include loose terminals, poor contact, damage to cable sheathing, moisture ingress, animal damage, damage during mowing operations, and deterioration with age. Because these issues are often difficult to detect from appearance alone, beginners should avoid touching equipment and making judgments. It is important to organize information such as the equipment showing abnormalities, the time of occurrence, changes in power generation, on-site photos, and the surrounding environment, and, if necessary, arrange for a professional inspection.

Cables are parts that are highly susceptible to the site environment. In areas with heavy weed growth, it becomes difficult to check their condition. During grass-cutting work there is also a risk of coming into contact with the cables. In poorly drained locations, moisture and puddles can affect the connections. At power plants where animals can easily enter, cable damage can also occur. It is important not to view electrical faults in isolation, but to inspect them together with the surrounding environment.

Even a small difference in power generation can lead to a large loss if it persists over the long term. Furthermore, if poor connections or damaged cables are involved, this can lead not only to reduced power output but also to safety risks. Beginners should not assume there is no problem just because overall power generation has not fallen significantly; instead, they should start by checking whether any individual pieces of equipment are underperforming and accurately share the locations that may be abnormal.

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Places to Check 5: Conversion Equipment and the Environment Around the Equipment

The causes of underperforming power generation are not limited to the panels and wiring. Even with sufficient solar irradiance, power output will not increase if the equipment that converts the generated electricity is stopped or if its output is being limited. When beginners consider how to increase power generation, they should not look only at the panel surfaces but also check the operating status of the conversion equipment, shutdown history, alarm history, and whether output is being curtailed.

When reviewing downtime history, check which equipment stopped, when it stopped, and for how long. Even short downtimes can cause significant losses if they occur during daytime when power generation is high. If equipment repeatedly stops and restarts during the day, it may not stand out in the monthly total, but in reality it can still result in lost generation. The suspected causes differ depending on whether only a particular piece of equipment stops or multiple pieces stop simultaneously.

When output curtailment occurs, power generation can plateau even on sunny days. If the upper part of the power generation curve appears flat, check operational data and history. However, a flat curve does not necessarily indicate output curtailment. Similar patterns can be caused by equipment capacity limits, temperature rise, soiling, shading, or measurement anomalies. Do not judge solely by the power generation curve; it is important to verify against equipment records and on-site conditions.

The surrounding environment of conversion equipment is also important. Conditions such as overgrown weeds around the equipment, poor ventilation, excessive dust and deposits, or a tendency for heat to build up can affect operational efficiency and the risk of shutdown. Even if the equipment itself shows no abnormalities, poor surrounding conditions can hinder stable operation. It is important to keep the area around the equipment easy to inspect, well ventilated, and in a state where any abnormalities can be checked immediately.

Solar power generation is more effective the stronger the solar irradiance, but when temperatures rise, output can sometimes fail to increase as much. If, on a clear summer day, generation does not rise to expected levels, check not only the irradiance but also the panel temperature and the temperature around the equipment. If weeds are proliferating beneath the panels, if there is grass or obstacles around the equipment, or if dust and deposits are making heat dissipation difficult, these can affect the increase in power generation.

For measures that beginners can take, first keep the area around the equipment visible and easy to inspect. Check whether it is covered by grass, whether walkways are secured, whether abnormal indicators are easy to check, and whether conditions might allow heat to build up. Internal checks of electrical equipment and detailed assessments require professional handling, but if you organize operation logs, the times when power generation drops, and on-site photos, it will be easier to narrow down the cause.

Checkpoint 6: Drainage, Topography, and Ease of Inspection

What beginners should look at last are the site's overall drainage, topography, and ease of inspection. When thinking about how to increase power generation, people tend to focus only on panels and equipment, but if the site environment is poor, dirt, weeds, poor connections, and delayed inspections will recur. Locations where water easily accumulates, where sediment flows in, paths prone to becoming muddy, slope failures, scour around the racking, and places where cables are likely to be exposed all cause direct or indirect reductions in power generation.

Poor drainage may seem to have little direct connection to power generation. However, in areas where puddles remain after rain, weeds tend to grow more easily. When weeds grow, they create shading, reduce airflow, and make inspections more difficult. Muddy access paths slow work and can reduce the frequency of cleaning and weeding. In places where sediment flows in, it accumulates under panels and around cables, causing soiling and damage.

When checking terrain and drainage, on-site inspections not only in fine weather but also after rain are effective. Determine where water flows in, where it accumulates, and where it drains out. Recording puddles, sediment deposits, vegetation overgrowth, subsidence of pathways, and changes in slopes will reveal locations prone to recurrence. If dirt or weeds recur in the same spots despite cleaning or weeding, you should suspect drainage or terrain problems rather than merely surface-level issues.

Ease of inspection also affects improvements in power generation. Locations that are difficult to inspect tend to have delays in detecting abnormalities. If grass has overgrown so you cannot pass through, the ground is too muddy to approach, equipment numbers are hard to read, or it is difficult to share the location of an abnormality, on-site response takes longer. Even if you identify underperforming equipment from data, if it takes time to reach the relevant site, improvements will be delayed.

When a novice inspects a site, they should check not only equipment that appears directly related to power generation, but also whether the site is easy to walk around, whether visibility is good, and whether it is easy to take photos to explain locations. At sites where inspection walkways are hard to find or equipment numbers are difficult to confirm on site, sharing information about abnormalities takes longer. To increase power generation, it is important to create a site environment that makes problems easy to detect and easy to address.

Improvements to drainage, site topography, and inspection routes may not immediately appear as large increases in power generation. However, reducing soiling, weeds, poor connections, and delayed inspections can help suppress long-term generation losses. For beginners considering how to increase power generation, it is important to look not only at the equipment itself but also at the environment that makes the equipment easier to manage.

Record-keeping for Beginners to Continue Improving Power Output

To continue improving power generation, it is essential to record the details of inspections. Beginners tend to notice things on site and leave it at that. However, efforts to increase power output are not completed by a single inspection or a single cleaning. Dirt will accumulate again, grass will grow, trees will grow, drainage paths will change, and equipment and wiring will change over time. Without records, you cannot learn the causes even if the same problems recur.

What you should record are the locations of equipment with low power generation, rows that are prone to soiling, places where shadows occur, areas where water accumulates, locations of poor connections, places that were repaired, and the ranges where cleaning or weeding was performed. Keeping photos, date and time, equipment numbers, work performed, details of abnormalities, response status, and whether a recheck is needed will be useful for the next inspection. If you increase the number of record items too much, it won’t be sustained in the field, so at first it’s important to make the records such that, when reviewed later, you can tell "where and what happened."

Linking power generation data with on-site photographs makes it easier to identify causes. If the positions of equipment with low generation coincide with locations of shadowing or poor drainage, the rationale for countermeasures becomes clear. If generation at a cleaned location improves, you can conclude that soiling had a significant impact at that site. If morning and evening generation improves after weed removal, it is highly likely that shading from weeds was the cause. Having records speeds up decision-making for future assessments.

When multiple people are responsible for management, being able to share the exact same location is important. In large power plants, similar rows and equipment are lined up, so it can be difficult to identify a location from photos alone. If equipment numbers, location information, and photos are recorded together, on-site staff, managers, inspection personnel, and repair personnel can more easily confirm the same location. Improving power output requires not only noticing issues on site but also recording that information in a form that stakeholders can share.

By continuing to keep records, the weaknesses of each power plant will become apparent. If you can identify patterns—grass growing in the same spots each year, dirt accumulating on the same rows, the same pathways turning muddy after rain, or the same equipment causing stoppages—you can take proactive measures before problems become larger. To increase power generation, it is important not only to respond after output declines but also to understand the conditions that make declines likely and prevent them in advance.

Record keeping may seem tedious for beginners. However, in practical work to improve power generation, whether records exist or not greatly affects the ease of decision-making. Simply documenting what you observed on site with photos and location data and cross-referencing them with power generation data will improve the quality of the next inspection. To learn how to increase power generation, you need not only to remember where to look but also to develop the habit of recording your observations and using them next time.

Summary

When a beginner learns how to increase power generation, it is important not to start with difficult technical terms but to first identify, in order, the areas to inspect. In solar power generation, you cannot increase the solar irradiance itself at the site. However, you can reduce generation losses by bringing the system closer to a state that converts received solar irradiance into electricity without waste. To do that, you need to check, in order, the power generation data, the panel surface, sources of shading, connection points and cables, conversion equipment, and drainage and terrain.

The first thing to check is the power generation data. Not only the monthly and annual totals, but also the generation by time of day, by equipment unit, and the generation curves for sunny days should be reviewed. Next, inspect the panel surfaces for dirt and deposits. Band-like dirt along the lower edge, bird droppings, fallen leaves, and dust can lead to reduced output. After that, check for shadows from weeds, trees, and surrounding structures. Because shadows change with the time of day and season, it is important to inspect the site at the times when generation is low.

Additionally, we check for differences in power generation at the string level, connection points, and the condition of the cables. If only some equipment shows low output, we suspect not only soiling or shading but also electrical faults. For power conversion equipment, we review shutdown history, alarm history, output curtailment, and the ventilation and temperature conditions around the equipment. Finally, we check drainage, terrain, and ease of inspection. Puddles, sediment buildup, mud, and poor access routes can be factors that lead to recurring soiling, weed growth, and inspection delays.

Improving power output is not something that can be completed with a single operation. Even after cleaning, dirt will return; even after weeding, grass will regrow; trees will grow; and drainage routes will change. Comparing power output before and after countermeasures, keeping on-site photos and work records, and applying them to the next inspection will improve the accuracy of improvements. For beginners to learn how to increase power output, it is important to check the causes of power loss in order and to maintain record-keeping that prevents the same problems from recurring.

Especially at large power plants, a system is needed to accurately share problem locations. If you record the locations where shadows occur, rows that are prone to soiling, places where water pools, abnormal strings, repair locations, and inspection photos together with positional information, stakeholders can more easily confirm the same location. By combining power generation data with on-site positional information, it becomes easier to explain the prioritization of countermeasures, and subsequent inspections and recurrence checks can be streamlined.

If you want beginners to put methods for increasing power generation into regular practice, utilizing LRTK is also effective. As an iPhone-mounted GNSS high-precision positioning device, LRTK is useful for recording inspection locations within a solar power plant, locations where shadows occur, drainage failure points, abnormal equipment, repair locations, and on-site photos together with high-precision positional information. Not only by checking the six locations to look at, but by keeping the results together with accurate positional information, even beginners will find it easier to continue improving power generation.