How to Maximize Your Commercial Solar Power System
At Sun-Wind Solutions, we see first-hand how vital commercial solar installations are for powering businesses, industrial institutions, EV charging stations, and more. Despite solar power’s rapidly evolving technological advantages, energy loss is still a significant issue. If your business is not paying close attention to optimizing your solar energy output, you may compromise its effectiveness and profitability.
After over a decade in the industry, we have seen a fair amount of PV panels that are not living up to their potential.
Here are some things to keep in mind to maximize the output of your solar system:
How Much Energy Will Be Lost From Solar Panels Each Year?
According to the National Renewable Energy Laboratory (NREL) research, the typical solar panel loses .75% of its output annually. Extreme weather events, however, can permanently increase your energy loss if not addressed.
Factors Contributing to Solar System Energy Loss:
The causes of solar energy loss on a flat roof installation fall into four general categories: DC inefficiency, wiring and connections, environmental effects, and other factors.
DC Inefficiencies
DC power losses refer to the factors that decrease the production of direct current (DC) energy generated by solar panels before converting into an alternating current (AC) used in homes, businesses, or in the case of net metering, the electric grid. Addressing these losses is key to enhancing the efficiency of your solar installation.
Temperature effects
Solar panels are sensitive to temperature fluctuations and higher temperatures generally decrease efficiency. Too much heat in hot days and summer months can result in lower function and productivity. This is of course impossible to control but an awareness of the issue will help you understand all of the factors affecting your systems energy output.
Nameplate Rating Loss
Nameplate rating loss accounts for the divergence between the stated power of a module in the datasheet and its operational performance under Standard Test Conditions. This loss is negligible in modern modules due to accurate datasheets. However, for older modules, a small loss might be factored in. This is a good reason to install solar panels that accurately report performance.
Mismatch Loss
Mismatch loss originates from slight variations in the electrical characteristics of installed modules. This loss impacts the system’s DC power output and can be higher in systems with a broader error range on rated power. Some PV modeling tools also include disparities in string lengths, cloud shading, and edge effects as part of mismatch loss. DC optimizers or microinverters can effectively reduce mismatch loss to near zero by tracking the maximum power point for each connected module.
Light-Induced Degradation
Light-induced degradation (LID) can sometimes take solar panel owners by surprise. LID is the degradation that occurs in a solar cell within a few days of installation due to sunlight exposure. This degradation, which impacts a significant segment of the crystalline-silicon cell market, can result in 1-3% losses.
LID affects solar cells based on their crystal structure (monocrystalline or multi-crystalline) and electrical properties (P-type or N-type). Monocrystalline solar cells, typically made using a process that promotes a uniform crystal structure, have better electrical properties but are more affected by LID. Conversely, multi-crystalline cells, cheaper to produce and less efficient, exhibit less LID due to smaller oxygen concentrations.
The formation of boron-oxygen compounds in solar cells commonly causes LID. Some manufacturers, such as SunPower, use n-type silicon, which doesn’t exhibit LID due to the absence of boron in the material.
Wiring and Connections
It’s important to understand that wiring and connector losses will always have an impact. However, proper material selection, installation, and maintenance will make a big difference in the effects of these losses.
Wiring Problems
A fundamental part of any PV system is its wiring. These conductive pathways transmit the energy harvested by solar panels to its destination—usually the grid or a battery storage system. However, they are also a source of power loss. The standard wiring losses in most PV systems are around 2%. This figure could be as low as 1% if a design includes thicker wires or very short runs, thereby reducing resistive losses.
The loss in energy can be attributed to the internal resistance within the wires, influenced by both the thickness and length of the wire. The National Electric Code specifies a minimum gauge for wires based on the voltage and current involved, ensuring safety against electrical fires. However, it does not set limits on wire losses, leaving it up to the installer to balance the decreased resistance offered by thicker wires against their increased cost.
PV Connection Losses
Aside from wiring, PV connection losses are another element that can contribute to the system’s overall performance. PV connectors, vital in connecting modules on series strings and to module-level devices, can experience a minor voltage drop. This drop is caused by the internal resistance of the material and imperfections in the contact surface. These losses typically average around 0.5%. However, time and corrosion can gradually increase losses so regular inspection and maintenance are required.
System availability, or rather its unavailability, is another factor resulting in the loss of power. Events that knock out the system entirely such as inverter shutdowns, grid outages, or other instances of disconnection result in the system failing to produce electricity. Typically, this translates into a 3% loss for most systems.
Inverter Inefficiencies
Inverter inefficiencies; Inverters convert direct current (DC) electricity generated by the solar panels into AC that can be used within your building. However they also have some losses that occur as well. It might be due to voltage drops or temperature differences or operating in non-optimal conditions, among other reasons.
Inverter Loss and Clipping
Solar system efficiency can also be affected by inverter losses and clipping. Inverters convert DC energy into AC energy. The efficiency losses of this conversion can vary based on the amount of capacity they are carrying, peaking around 20% and falling slightly with maximum input rating. Conversely, inverter clipping occurs when the output from the solar panels is at its maximum power and is greater than what the inverter can convert. If this happens in your solar power system, upgrading your inverter to a high capacity and efficient inverter will recapture the energy you are losing.
Environmental Factors
Factors such as tilt and placement, environmental conditions, and temperature coefficients can affect the overall efficiency of a solar panel system.
Shading
Shading from nearby buildings or trees can significantly decrease the sunlight reaching solar panels, reducing their production. In fact, even partial shading on just a few panels could greatly affect overall system performance.
Dust & Debris
Dust, dirt, and pollen accumulate on the surface of solar panels, preventing full sunlight from reaching them and reducing their overall efficiency. This is why regular cleaning is a critical part of solar panel maintenance.
Soiling Loss
Soiling loss refers to the accumulation of dust, grime, and other debris on solar panels which block sunlight, and thereby reduce a photovoltaic (PV) system’s ability to convert sunlight into electric energy. It is a significant contributor to PV system losses, with an industry standard of 5% typical soiling loss, varying between 2% to 25%.
Factors contributing to soiling loss differ dramatically based on the location of the solar panels. Wind, exposed soil, local traffic, rainfall frequency and strength, and even the number of birds in the area can all affect the rate of soiling. Studies tracking soiling losses across the United States have identified variations between different regions, with systems in central California showing a 4-5% loss, while those on the Texas plains sit around just 1%. In Connecticut, we deal with bird waste, fallen leaves, and general dust from wind, traffic, and local activities.
Rainfall has been identified as a major factor influencing soiling loss, with areas that experience regular rain maintaining lower soiling rates. However, not all types of soiling are easily washed away by rain. Bird droppings, for example, often require manual cleaning and can block a substantial amount of light on the impacted cells.
Snow Loss
During the snowy season, solar panels can experience significant power loss. Snow cover blocks sunlight from reaching the panels, effectively halting production until it slides off the panels or melts away. The amount of snow loss depends on several factors, including the tilt of the panels, duration and intensity of snowfall, ambient temperature, and wind conditions. Studies suggest that snow losses may range from 10-30% for fixed-tilt systems.
Other Factors
Tilt and Placement Angle
One of the key factors that affect a solar panel’s efficiency is the tilt and placement angle. Ideally, a solar panel should be placed at an angle equal to the latitude of the installation while facing the equator to maximize the incident irradiance or sunlight. The performance can be easily tracked using advanced software modeling, as it allows precision in quantifying these differences.
Solar Incidence Angle
Another important factor is the Solar Incidence Angle, which refers to the angle of the panel’s surface compared to the sun’s rays. This angle can affect the amount of sunlight passing through the panel’s glass front. Therefore, the modules should be tilted a bit less than the latitude and oriented toward the equator to reduce Incident Angle Modifier losses.
Degradation Over Time
System degradation is another environmental factor affecting the power output of solar panels. Similar to any technical equipment, the materials in solar cells gradually lose efficiency over time. This degradation can be attributed to the effects of thermal expansion and contraction, UV light exposure, and damage from airborne particles.
Here’s how you can boost your solar panel power production:
Maximizing Solar Panel Production
Harnessing the power of the sun has never been more affordable. Solar panels are now a regular sight on rooftops across Connecticut, serving as a testament to the world’s shift toward renewable energy. However, achieving maximum efficiency from your solar panels involves more than just installation.
Start with High-Efficiency Models
Remember, all solar panels are not created equal. Investing in high-efficiency solar panel models for the best results is essential. Modern solar cell technology has significantly improved, with average efficiencies increasing from 15% to about 20%. Certain models, such as those produced by LG and Sunpower, can boast efficiencies of about 22%. While these may come with a higher initial cost, their superior performance pays off in the long run. Your Sun-Wind Solutions representative will go over these options with you during your consultation.
Consider High Concentrated Photovoltaic (CPV) Cells
For those after the highest possible efficiency, High Concentrated Photovoltaic (CPV) panels are worthy of consideration. These panels focus sunlight on specially designed cells which have recently reached a record 47% efficiency level. While expensive and less available than traditional models, CPV panels can be a smart investment if you can afford the upfront costs.
Placement Matters
Proper site selection and design is of great importance to achieve maximum sunlight exposure while minimizing shading. Through a complete site analysis before installation, potential sources of shading can be identified, and panel orientation and tilt angles can be optimized for high sunlight exposure.
The location of your solar panels can significantly affect their power production. Avoid locations shaded by tall trees or other buildings to prevent the power output drop. The orientation and angle of your panels are also crucial, with an angle of 18 to 36 degrees typically offering optimal sunlight exposure. Both the angle and spacing are critical so that the array does not self-shade during our long Connecticut winters.
Professional Installation
Proper installation is key to ensuring solar panels absorb the maximum amount of sunlight. Factors like orientation, angle, and spacing will impact performance. It’s worth getting experts like our team at Sun-Wind Solutions to install your solar panels to guarantee they’re set up for maximum efficiency.
Regular Maintenance
A good plan that fully covers regular cleaning, inspection, and overall maintenance of solar panels, inverters, other electrical components, etc., helps curb energy lost due to soiling or equipment malfunctioning over time.
Keep your panels clear from dust and dirt that can hinder their performance. While solar panels require minimal maintenance, occasional cleaning can prevent efficiency losses of up to 20%. Take a look at Sun-Wind solar panel maintenance services for solar developers.
Monitor Your Solar Panel Output
Finally, keep an eye on your solar system’s performance using energy management software. Advanced analytical tools can provide real-time system performance insights and help identify issues in a timely manner. Remote monitoring systems detect shading, inverter failures, and other anomalies, thus enabling preventive maintenance or optimization of your solar PV system. At Sun-Wind Solutions, we support several monitoring systems to track your solar performance and can address issues quickly.
Inverter Selection & Optimization
We choose high-quality inverters that are sized properly, configured correctly, and installed correctly to minimize inverter inefficiencies and ensure maximum power is harvested from your panels.
Temperature Management
Solar systems lose about 1% of their efficiency for every degree over 77°F (or 25°C). That’s why it’s important to elevate the panels a few inches above the surface of your roof to allow for air circulation. A good solar panel company will take climate into consideration during installation. Your Sun-Wind Solutions team may install ventilation, shade structures, or active cooling devices for flat roof systems to mitigate the impact of high temperatures on your solar panel functioning.
Considerations For Flat Roof Solar Installations
When it comes to green energy solutions, solar panels are among the most popular options. Yet, their installation isn’t always as straightforward as one might hope, especially on flat roofs. Many businesses encounter challenges when installing solar panel systems on a flat roof. Let’s delve into each of these potential complications.
How Roof Slope Affects Energy Production
Solar energy efficiency is significantly influenced by roof slope. According to data from the Department of Energy (DOE), a south-facing sloped roof system is ideally situated when tilted at an angle between 15 and 40 degrees. Most residential rooftops in the U.S. generally fall within this range, specifically between 18 and 34 degrees. However, most businesses do not have sloped roofs. Therefore, most companies will need to accommodate the longevity of their roof, and the optimal solar panel angles using a panel mounting system. Sun Wind Solutions has years of experience working with roofing companies to make sure that the roof and solar panels are good neighbors!
Solar panels on east-west roofs can function effectively on steep angles, but perform optimally at shallower angles. This is because they enjoy more sunlight during the midday hours. The best setup would be completely flat, but in reality, a slight tilt maximizes electricity production by facilitating the removal of obstructions like dust, leaves, and snow.
Sunlight Intensity
Firstly, sunlight intensity affects the production output of solar panels. Installing solar panels flat won’t capture the same sunlight intensity as angled panels, so solar panels on a flat roof generally produce less power than sloped roofs. This can be problematic for those looking to reduce installation costs without compromising power production.
Dirt and Debris
Secondly, solar panels on flat roofs tend to accumulate more dirt, pollen, and debris than their angled counterparts. Since angled panels naturally get cleaned by rainwater, their efficiency remains high. However, flat panels don’t have this self-cleaning advantage, causing a buildup of debris that reduces their efficiency over time. This is why it’s important to set up ongoing maintenance with Sun-Wind Solutions to keep your panels clean and your electric bills low.
Water Damage
Water damage also poses a significant concern for flat roof solar installations. If panels are mounted parallel to the roof, water will naturally pool on top, and during winter, snow can easily accumulate. This situation leaves solar panels more susceptible to water damage, potentially reducing their lifespan. Notably, some manufacturers even waive the 25-year equipment warranty generally provided if the panels are installed flat.
Shading
Lastly, the likelihood of shading is higher on flat roofs. Although trees or nearby buildings can shade any roof, flat roofs come with their own shade-casting obstacles, such as parapet walls and HVAC equipment. Consequently, experts at Sun-Wind Solutions will plan carefully to install panels away from these protrusions and avoid shading during sunlight hours.
Optimize Your Solar Panel Energy Production With Sun-Wind Solutions
Sun-Wind Solutions is proud to be Connecticut’s premier solar panel installation and maintenance company. Our expertise isn’t limited to commercial roofing; we also offer comprehensive services from equipment provision to structural supports and connection establishment. We work with you to develop a solar system that meets your power needs and budget, boosting your business with utility cost reductions and tax incentives. As a full-service Solar EPC company since 2010, we’ve consistently handled diverse projects from rooftop systems to ground-mounted arrays and carports.
Investing with us reduces your operating costs and significantly contributes to a cleaner and healthier community. Sun-Wind Solutions experienced professionals pride themselves in flawless execution and complete client satisfaction, including solar panel procurement, installation, and maintenance. Whether you’re just getting started on your commercial solar journey or looking to optimize the efficiency of your current solar panels, we’re confident in our ability to deliver the best customer experience from start to finish. Contact Sun-Wind Solutions today for a free consultation. You’ll be glad you did!