5 Quick Ways to Increase Power Output｜Key Points for Reviewing Solar Power Equipment

Table of Contents

• The shortcut to increasing power generation begins with assessing the current condition of the equipment

• Shortcut 1: Use power generation data to pinpoint the time of decline and narrow the scope of affected equipment

• Shortcut 2: Prioritize checking panel surface soiling and shading

• Shortcut 3: Review abnormalities in strings, connection points, and cables

• Shortcut 4: Check power conversion equipment, temperature conditions, and ventilation

• Shortcut 5: Organize drainage, site topography, and inspection records to prevent recurrence

• Operational design to sustain increased power generation

• Summary

The shortcut to increasing power generation begins with understanding the current condition of the equipment

When you want to increase the power generation of a solar PV system, the first important thing is not to immediately consider adding equipment or undertaking large-scale renovations. At many sites, there are still causes that prevent existing equipment from delivering the power it should. Dirt on the panel surface, bird droppings and fallen leaves, shading from weeds and trees, faults in connections, cable damage, inverter shutdowns, output curtailment, temperature rises, poor drainage, and site conditions that make inspections difficult — there are multiple factors that reduce power generation.

For practitioners searching for "how to increase power generation," the important thing is not to think of boosting generation as some special trick. With solar power generation, you cannot increase the amount of sunlight at the site. You also cannot increase the number of sunny days or change the seasonal solar altitude. However, you can move closer to a state in which the received sunlight is converted into electricity with as little waste as possible. In other words, the practical shortcut to increasing generation is to quickly identify the generation losses in the existing equipment and reduce them in order of those with the greatest impact.

A common pitfall when power output is low is deciding the cause based only on on-site appearance. Cleaning because the panels are dirty, removing weeds because vegetation has grown, or suspecting the equipment side because the devices look old—such judgments are sometimes necessary. However, if the primary cause of the drop in power output lies elsewhere, those actions will not improve output as much as expected. For example, even if you clean the panels, power generation will not fully recover if morning and evening shadows remain. Similarly, even if you remove the weeds, daytime power output will not increase if brief shutdowns of the inverters continue.

To efficiently increase power generation, first check the generation data to determine during which time periods, at which facilities, and to what extent output is declining. Then inspect the site to see whether problems are caused by soiling, shading, connection points, equipment, drainage, or inspection routes. By isolating the causes and then implementing countermeasures, you can concentrate limited inspection and work time on the areas that have the greatest impact on power generation.

The shortcut to increasing power generation is not to skip tasks. Rather, it means reducing unnecessary work and focusing on checks and measures that are most likely to produce results. Cleaning, weeding, repairs, equipment inspections, drainage measures, and record management are more effective when linked to power generation data and on-site conditions than when carried out individually. Below, we explain five shortcuts to prioritize when reviewing solar power facilities, laid out in a workflow that is practical for field operations.

Shortcut 1: Use power generation data to narrow down the time of decline and the scope of affected equipment

The quickest way to increase power generation is to check the generation data before going to the site. If you only look at monthly or annual generation, you won't know when and where generation losses are occurring. Even if nothing looks abnormal on a monthly basis, generation may drop during certain hours of sunny days, or output may remain low only for specific rows, specific strings, or the area connected to specific conversion equipment.

Viewing by time of day makes it easier to identify the likely direction of the cause. If generation is low in the morning, shadows from trees on the east side, slopes, nearby structures, or adjacent equipment may be involved. If it is low in the evening, check for shadows on the west side and the effects of surrounding terrain. If the midday peak does not reach expected levels, candidates include soiling of the panel surfaces, temperature rise, limitations of power conversion equipment, output curtailment, or equipment shutdowns. If the generation curve suddenly drops during a sunny day, you need to cross-reference shutdown logs and alarm histories with the time.

When comparing on a per-equipment basis, it is important to compare units under the same conditions. If you simply compare systems that differ in orientation, tilt, number of panels, shading conditions, or connection configuration, you risk misinterpreting normal differences as abnormalities. If a specific area is consistently lower compared with adjacent rows or equipment with the same orientation, suspect localized soiling, partial shading, connection faults, cable damage, or abnormalities in the power conversion equipment.

Also pay attention to how the power generation declines. If it drops suddenly, possible causes include equipment shutdown, wiring faults, poor connections, or the emergence of obstructions. If it is decreasing gradually, possible factors include accumulation of dirt, growth of weeds or trees, deterioration of site conditions due to poor drainage, and aging of equipment or components. By interpreting the pattern of the decline, you can narrow down the locations that should be checked on site.

When checking power generation data, use sunny days as the baseline whenever possible. On cloudy or rainy days, power output can fluctuate greatly due to cloud movement, making it difficult to distinguish from equipment abnormalities. With the generation curve on a sunny day, it is easier to identify features such as shading, shutdowns, curtailment, and string-level abnormalities. When you're in a hurry to increase power generation, a shortcut is to narrow down the time of decline and the scope of affected equipment using data, rather than jumping straight into on-site work.

Quick Tip 2: Prioritize checking the panel surface for dirt and shadows

When prioritizing on-site checks to increase power generation, dirt on the panel surface and shading should come first. Both are factors that directly reduce the amount of light received and are relatively easy to inspect on site. Because solar panels generate electricity by receiving solar radiation at the surface, dirt and deposits reduce the light reaching the cells. The type of soiling varies depending on site conditions: soil dust, pollen, yellow dust, bird droppings, fallen leaves, tree sap, dust from nearby construction, road-derived dust, and salt-containing deposits that readily adhere in coastal areas.

What requires particular attention is the band-like soiling that remains along the lower edge of panels and around the frame. It is often assumed that rain will wash it away naturally, but in reality the flow of rainwater can gather dirt at the lower edge and leave it there. Panels with a gentle tilt drain poorly, making them more prone to dirt accumulation. Even soiling that is not noticeable from a distance can affect power generation if it covers part of a cell.

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

On the other hand, the cause of a reduction in power output may be shading rather than soiling. Causes of shading include weeds, trees, fences, utility poles, nearby buildings, mounting structures, adjacent rows of panels, and monitoring equipment. Because shadows move with the time of day and the seasons, the fact that no shadow was seen at the time of an inspection does not necessarily mean there is no problem. If output is low in the morning, check the site conditions in the morning; if it is low in the evening, check for evening shadows. Even if there is no problem at noon, large shadows can appear in the morning or evening.

When performing cleaning or weeding, prioritize areas that have the greatest impact on power generation. If the equipment with low power output coincides with the areas of dirt or shading, the priority for countermeasures increases. Conversely, even if dirt or weeds are noticeable, if the main cause of the power generation decline is equipment shutdowns or connection failures, cleaning or weeding alone may not lead to improvement. When inspecting panel surfaces and shading, it is important not to rely on appearance alone but to cross-check with power generation data.

Shortcut 3: Re-examine strings, connectors, and cables for abnormalities

As a shortcut to increasing power output, checking for abnormalities in strings, connection points, and cables cannot be overlooked. Even if panels are receiving sunlight normally, if there is a fault in the path that extracts the electricity, the generated power cannot be fully recovered. Even when there appear to be no major visible abnormalities, if only a specific string shows low output, the system becomes unstable after rain, or output is lower than surrounding arrays even on sunny days, electrical faults should be suspected.

When checking for anomalies at the string level, compare units under the same conditions. If you simply compare units that differ in panel count, orientation, tilt, shading conditions, or connection configuration, you may mistakenly judge normal differences as abnormalities. Check whether any string is consistently lower compared with adjacent rows or equipment with the same orientation. If only a specific string is low, candidates include soiling, partial shading, poor connections, cable damage, or problems on the equipment side.

Problems with connections and cables include loose terminals, poor contact, damage to cable sheathing, moisture ingress, damage caused by animals, damage during mowing operations, and deterioration due to aging. These can be difficult to detect from appearance alone. By narrowing down abnormal ranges using power generation data and cross-checking with on-site photos, occurrence time, weather, and the surrounding environment, it becomes easier to prioritize inspections.

Safety must be the top priority when inspecting electrical equipment. Just because you want to increase power output, on-site personnel should avoid forcibly touching connection points or the interior of equipment to make a determination. Compile information on the equipment showing abnormalities, the time of occurrence, changes in power output, on-site photos, and the surrounding environment, and, if necessary, arrange for a specialized inspection. At the stage of identifying the cause, it is important to clarify where and what kind of abnormality is suspected.

Faults in connections and cables may be related to the surrounding environment. In areas with heavy weed growth, it becomes difficult to inspect the condition of cables. In locations with poor drainage, moisture and standing water can affect connection points. On sites prone to animal intrusion, cable damage can also occur. Rather than stopping at repairs, confirming site conditions that can lead to recurrence is essential for improving the power output of solar installations.

Shortcut 4: Check conversion equipment, ambient temperature, and ventilation

Low power output isn't caused only by panels and wiring. If the equipment that converts the generated electricity is stopped or its output is limited, generation won't increase even when solar irradiance is sufficient. When reviewing a solar power installation, it is important to check the operating status of the conversion equipment, shutdown history, alarm history, and whether output curtailment is in place.

When reviewing downtime history, check which equipment stopped, when it stopped, and for how long. Even a short stoppage can cause large losses if it occurs during daytime when generation is high. If equipment repeatedly stops and resumes during the day, it may not stand out in the monthly total, but in reality you could be missing generated energy. Whether only specific equipment stops or multiple pieces of equipment stop simultaneously will change the suspected causes.

If output curtailment occurs, power generation can plateau even on sunny days. If the upper part of the generation curve appears flat, check operating information and historical records. However, a flat curve does not necessarily indicate output curtailment. Similar shapes can be caused by equipment capacity limits, temperature rise, soiling, shading, or measurement anomalies. Do not judge based only on the generation curve; it is important to verify with equipment logs and on-site conditions.

Temperature conditions are another point to review. While solar power generation is easier with stronger sunlight, higher temperatures can sometimes limit the increase in output. If generated power does not rise as expected on a clear summer day, check not only the solar 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 making heat dissipation difficult, these can affect the increase in power generation.

Conversion equipment and surrounding components are affected by environmental factors during long-term operation. Conditions such as poor ventilation around the equipment, being covered by grass and difficult to inspect, or being easily affected by rainwater and sediment can all delay the detection of abnormalities. The quickest way to increase power generation is not just to look at the equipment itself, but to prepare the surrounding environment so the equipment can operate stably. Keeping the area around equipment easy to see, well ventilated, and in a state where any abnormalities can be checked immediately helps enable early detection of generation losses.

Shortcut 5: Organize drainage, topography, and inspection records to prevent recurrence

To prevent improvements in power output from being only temporary, it is important to review drainage, terrain, and inspection records. Even if you only check panels and equipment, on sites where the same power losses recur, the cause may lie in the overall environment of the plant. Areas where water easily accumulates, where sediment flows in, paths prone to becoming muddy, slope failures, scouring around racking, and places where cables are likely to become exposed can lead to dirt, weeds, connection faults, and reduced accessibility for inspection.

In areas where puddles remain after rain, weeds tend to grow more easily. When weeds grow they create shading, reduce ventilation, and make inspections more difficult. Muddy pathways can slow work and lower the frequency of cleaning and weeding. Where sediment flows in, it can accumulate under panels and around cables, causing soiling and damage. If cleaning and weeding repeatedly fail to resolve the same problem in the same location, drainage or topography issues should be suspected.

When inspecting terrain and drainage, on-site checks not only in fine weather but also after rain are effective. Determine where water is flowing in from, where it collects, and where it drains out. Recording puddles, sediment accumulation, vegetation overgrowth, path subsidence, and changes to slopes will reveal locations prone to recurrence. If poor drainage is left unaddressed, dirt and weeds will recur, resulting in the same power generation losses occurring repeatedly.

Inspection records are also a shortcut to boosting power generation. If you can confirm whether the same location has shown soiling in the past, whether grass has grown in the same row, or whether the same equipment has experienced stoppages, you can narrow down the cause more quickly. If records are insufficient, start keeping photos, date and time, equipment numbers, location, details of abnormalities, and the status of responses from this inspection so they can be used for the next inspection.

To prevent recurrence, it is also essential to compare power output before and after countermeasures. After performing cleaning, weeding, repairs, equipment checks, and drainage checks, record the power output before and after the work, on-site photos, the scope of work, and weather conditions. Prioritize measures that produced significant effects in subsequent inspections, and if an effect is not clearly visible, suspect another cause. The shortcut to increasing power generation is to streamline the next inspection using past records rather than searching for the cause from scratch each time.

Operational design to sustain increased power generation

Improving power generation cannot be completed with a single inspection or measure. A solar power plant is an outdoor facility, and its condition changes with the seasons, the weather, the surrounding environment, and the aging of equipment. Even if you clean it, dirt will return; even if you remove weeds, grass will grow back; trees will grow; and equipment and wiring will change condition through long-term operation. To stably increase power generation, an operational design that continues inspections and countermeasures is necessary.

First, the important thing is to establish the criteria for checking power generation. Decide how frequently you will review generation data, at what level of decline you will conduct on-site inspections, and down to which equipment unit you will make comparisons; doing so will speed up anomaly detection. Relying solely on the intuition of the person in charge can lead to oversights and inconsistent judgments. By standardizing the generation curve for sunny days, comparisons with equipment under the same conditions, checks of downtime history, and the recording of on-site photographs, the precision of improvements will become more consistent.

Next, decide the priority of countermeasures. If you try to solve all issues at once, the workload increases and measures that have a significant impact on power generation may be postponed. Prioritize checking equipment that shows a clear decline in power generation data, shadows with long durations of impact, recurring soiling or drainage failures, and equipment that experiences frequent stoppages even for short periods. The quickest way to increase power generation is to address measures in order, starting with locations that have the largest generation losses.

When management involves multiple personnel, a system that allows precise sharing of the same location is also necessary. In large power plants, similar rows and equipment are often lined up, so photos alone can make it difficult to identify locations. If equipment numbers, location information, photos, and work histories are recorded together, on-site staff, managers, inspectors, and repair personnel can more easily confirm they are referring to the same location. Improving power generation is also about building a system that leverages on-site observations for the next round of improvements.

In operational design, it is important not only to respond after power generation declines but to identify in advance the conditions that tend to cause declines. If you record rows that easily accumulate dirt, times of day when shading is likely to occur, locations where water pools, sections of walkways prone to damage, and equipment likely to show abnormalities, you can check them before power output drops significantly. To sustain increases in power generation, inspections must not be treated as mere checks but must be accumulated as information to inform the next countermeasures.

Summary

A shortcut to increasing power output is to correctly identify generation losses in solar installations and make improvements starting with the locations that have the greatest impact on output. In solar power generation, you cannot increase the solar irradiance at the site itself. However, you can improve output by bringing the system closer to a state in which the received irradiance is converted into electricity without waste. To do this, it is necessary to check, in order, the power output data, panel surface soiling, shadows from weeds and trees, strings and connection points, power conversion equipment, drainage and topography, and inspection records.

When you feel that power generation is low, rather than immediately performing cleaning or repairs, it is important to first break down and examine the data. Determine when the output is low, which equipment is underperforming, and whether there are differences compared with equipment under the same conditions. With that information, an on-site inspection will make clear which places need cleaning, the extent of weeding required, which connections should be checked, which devices need inspection, and which drainage or traffic routes should be reviewed. To maximize the effectiveness of power-generation improvements, it is important to make decisions by linking data with on-site conditions rather than relying on intuition.

Also, increasing power output cannot be accomplished with a single action. Even if you clean, dirt will return; even if you remove weeds, grass will grow; trees will continue to grow; and equipment and wiring will change condition over time. By comparing power output before and after countermeasures, keeping on-site photos and work records, and applying them to the next inspection, the accuracy of improvements will increase. To raise power output consistently, it is essential not only to remove the causes but also to create a site environment and management system that make the same causes less likely to recur.

In particularly large power plants, a system for accurately sharing problem locations is important. If you record rows prone to soiling, areas where shadows occur, places where water pools, abnormal strings, repair locations, cleaning areas, and inspection photos together with location information, stakeholders can more easily verify the same spots. By combining power generation data with on-site location information, it becomes easier to explain priorities for cleaning, weed removal, and repairs, and it also streamlines verification of recurrence in subsequent inspections.

If you want to continuously pursue a quicker way to increase power generation based on field data, using LRTK is also effective. LRTK, an iPhone-mounted GNSS high-precision positioning device, is useful for recording inspection points within a solar power plant—such as areas prone to soiling, locations where shadows occur, poor drainage spots, abnormal equipment, repair locations, cleaning ranges, and on-site photographs—together with high-precision position information. By keeping equipment review points with location information, it becomes easier to carry out power generation improvements based on field data rather than on intuition.