Solar energy is one of the most reliable and efficiently clean renewable energy this modern times. Even tech revolutionaries and retail giants Apple, Amazon, Target, and Walmart, adopted solar energy generating a combined 1,081.6 MW of solar electricity.
When investing in solar energy to power up your home’s electricity needs, you want to ensure that you fully maximize the investment. Do solar panels go bad if not used? Will solar panels degrade in storage?
Although solar panels have no expiration dates, too much exposure to hazardous factors may degrade their materials.
In this article, we have got the answers to everything you need to know about solar panels.
What Is A Solar Panel?
In Wikipedia, the solar panel is “an assembly of photovoltaic cells mounted in a framework for installation”. It is also known as photovoltaics, which means “light-electricity.” (source)
The solar panel is a device used to convert sunlight into electricity. It is composed of solar cells spread in a large area that works together to harness enough power for electrical loads.
It absorbs the photons from sunlight and, in doing so, initiates an electric current. Then, it allows electrons to be knocked out of their atomic orbits and released into the electric field generated by the solar cells, pulling these free electrons into a directional current.
The solar panel generates more power during the daytime than at night. Living off-grid in remote areas and cabins benefit nicely from solar panels. It is much less expensive and can provide power for over three decades if properly maintained.
Do Solar Panels Charge Faster In Series Or Parallel?
Wiring solar panels can be series or parallel; the main difference between these two is the output voltage and current. But, which system is better?
Wiring multiple panels in series add the output voltages together, but the output current remains the same. On the other hand, numerous wiring panels in parallel add the output currents together, but the output voltage remains the same.
Solar panels in series are best in unshaded conditions. A shade covering one panel will reduce the whole system’s power output. Series connection is also best if you need a low-amperage system. A higher voltage system requires lower amperage, which allows you to use smaller gauge wires which are less expensive and easier.
Best Conditions For Solar Panels
Solar panel in parallel works best in mixed-light conditions. Even if a shade covers one panel, the remaining panels in the array will continue to generate power as expected. It is ideal for a low voltage system using a lower-cost PWM controller.
Of the two, deciding which one is the best depends on the individual needs and application. However, the series connection charges faster. The low light conditions produce enough volts to begin charging the instant the light touches the panels, instead of slowly climbing until volts exceed charging voltage.
Do Solar Panels Go Bad If Not Used?
Technically, there is no expiration date on solar panels. But, over time, being exposed to changing weather and other elements, they naturally tend to become less efficient at producing energy.
Extreme weather conditions may break some panels and weaken their panels. Falling debris may develop microcracks that will eventually damage the entire panel. Water may also break the seal that protects the boards from water degrading.
Though they may stop working efficiently, solar panels have an average warranty of 25 years, though it will depend on the manufacturer. Twenty-five years is twice as long as it will take many people to recoup their investment, making it almost undoubtedly cash-positive. Nevertheless, solar panels will slowly depreciate over time.
Solar Panels May Still Go Bad When Not In Use
Technically, solar panels can still generate energy when they aren’t in use. But, the primary reason the solar panels are exposed to various elements that make the materials, including plastic, silicon, and aluminum, eventually degrade. It is regardless of whether used or not used.
Will Solar Panels Degrade In Storage?
According to the industry standard, the productive lifetime of the solar panel is 25-30 years from its manufacturing date. It can even work for decades, given they acquire physical damage by wind, debris, or other external factors. Well-maintained panels with the proper installation may even reach 50 years.
Panels slowly degrade, meaning they may produce less and less electricity. They will not die immediately but will decrease significantly in the output below what the manufacturer projected.
A 2012 National Renewable Energy Laboratory (NREL) found that average solar panel output falls by 0.8 percent yearly. Premium manufacturers offer degradation rates as low as 0.3%. This solar panel degradation rate constantly improves as solar panel technology gets better over the years. (source)
Their efficiency will decline gradually when solar panels are in storage and have never been used. Over time, panels may be gone to normal wear and tear from exposure to UV rays and adverse weather conditions.
What Causes Solar Panel Failure?
In general, there are types of degradation that can affect the solar panel, such as:
- Light-Induced Degradation (LID)
It pertains to the interaction between the crystalline silicon cells and the outside environment, which can last days or weeks.
- Direct Light-Induced Degradation (DLID)
It directly exposes electronics within the photovoltaic cells to sunlight during the initial setup period. It may warp or buckle from the heat.
- Uv Light-Induced Degradation (UVID).
The initial exposure to sunlight causes the crystalline silicon oxide on the panel’s surface to form a layer of boron dioxide, reducing efficiency.
- Potential-Induced Degradation (PID)
It can be caused by different components, such as the photovoltaic cells and the frame, operating at different voltages. It causes voltage leaks, reducing the electricity the panel can send to the inverter.
- Age-Related Degradation
High temperatures, heavy rainfall, snowfall, and ice causes hardening of the crystalline silicon, frame corrosion, and cell contamination.
Solar Panels Can Fail Because Of Other Several Factors
The quality of solar panels also determines their useful life. Some manufacturers use premium quality materials that can either shorten or lengthen the years that the panel can be efficient. Some cheaper products may use low-quality materials that can easily break.
Depending on the cost of investment, the solar panel will be useful depending on the quality. While it may have a lower initial price, it may be pricey more in the long run caused by a higher failure rate. Added to these, it may lead to the replacement of the whole system.
- Panel Assembly
The way you assemble the panel can affect its useful life. Not all materials work well together, even with high-quality materials. It is essential to go with trusted manufacturers as incompatible materials for the panel may accelerate LID or PID if they impact the amount of oxidation or voltage leak.
Proper handling is critical in solar panels to avoid damage. Microcracks, scratches, and improper electrical connections during installation may affect lifespan. Installing on the roof with optimal angle and clamping gets the most out of the self-cleaning and mechanical resistance. Hence, it can increase the lifespan.
Solar panels may not be a high-maintenance product. Still, it is essential to conduct regular monitoring to remove any build-up of dust or debris that could affect the electricity output.
Regular maintenance can improve the efficiency of solar panels. It is necessary to monitor if there is no shade or blockage in the panel that may affect its efficiency in harnessing solar energy. Also, ensure that connections, cabling, and inverters are not loose or broken.
How To Tell If A Solar Panel Is Bad?
There are signs that solar panel is terrible and not maximizing the output. Look at these signs to determine if the solar panel needs repair or replacement.
- The Inverter Has A Red Light
There should be a green light as it states that the solar panel is working well. If it is orange light, possible issues may arise. If the inverter has a red light, it alerts that there’s a problem or the system is at fault.
- The System Shuts Down Unexpectedly
In most solar panel models, the system can shut down when the voltage is too high or low or there is an issue with the earthing. You may need to check how much voltage drop the solar panel’s array experiences.
- The Meter Displays Power Consumption From The Grid
The solar meter must track your electricity consumption at home. It should show that solar panels supply the most energy and less from the power utility. If the solar meter displays consumption from the grid or power utility, there can be some fault with the solar installation.
- The Solar Meter Should Always Be On The Growth Trend During The Daytime
The solar panel must generate the most energy during the daytime. So, it must be on the increasing trend during the day. If it shows no changes in the kilowatt-hours of power, there are high chances of an issue with the solar system.
- Output Voltage Does Not Get At Least 80% Of The Rated Solar Panel Output
Measuring output voltage requires using a multimeter. It has a voltage range that can measure the maximum rated voltage of the module. If the output does not reach at least 80% of the rated output, then there is something wrong with the panel.
- Loose Wiring Or Connection
If there is some loose wiring or connection, it may cause electrical issues or reduce energy production.
- Solar Panel Heats At Excessive-High Temperatures
Too much heat and any other extreme temperature between 59°F and 95°F can damage the solar panel and reduce the solar system’s maximum effectiveness. It can reach temperatures up to 149°F in the summer, but its effectiveness will also suffer.
- The Solar Panel Is Dirty Or Damaged
The solar panel must be clear of any dirt and debris that can block the sunlight. It can prevent the system from generating enough energy, which can fail to flow around equally. Even microcracks may result in poor energy production.
- Broken Glass Is Exposed To Weather Damage
The glass protects the other solar panel materials from weathering, rust, and corrosion. If the glass is broken, it can weaken the absorption of sunlight.
- Snail Trails Show Up
Snail trails appear on the surface when a faulty front metallization substrate material is inside the solar cell production. It builds up moisture which may lead to oxidation between the silver paste and the EVA encapsulation content.
When Should You Replace Solar Panels?
Generally, damaged solar panels may generate power but won’t function or produce total energy. It is possible if at least 80% of solar cells are not damaged.
If the solar panel reaches at least 20 years, it is time to be more aware of the system. Though it is supposed to work for 25 years, you must perform scheduled maintenance to look for possible issues. Not only will it increase its efficiency, but it may also prolong the unit’s lifespan.
When the system reaches 25 years, it is advisable to consider replacing the solar panel system. Though it is built for durability and withstand the weathering in outdoor usage, the efficiency can drop after 25 years. Older models may have faults, normal wear and tear, weathering, degrading, or decreased electricity production due to age.
However, if the performance of the system declines and there are damages, it may need replacement. The frequency and the range of replacing solar panels depend on the manufacturer, panel type, and where you live.
Can You Replace Just One Solar Panel?
Replacing only one solar panel is possible, especially if the budget is constrained and the system is not yet ending its useful life. Replacing the entire system can be costly though it can generate substantially more power. However, there is a possibility of running out of the same model that best fits a specific system.
You must replace the solar panel with the same model, brand, or manufacturer. You also need to match the electrical specification. It ensures that it matches the whole system and avoids possible short circuits and failure.
Are Old Solar Panels Worth Anything?
Old solar panels that may have reached the end of their useful life have salvage value, which is the possible worth if the solar panel or any of its components has been sold. Old solar panels are worth something, so don’t throw them away.
Solar panels contain valuable quantities of silver. The silver in panels collects the electrons generated when the sunlight hits the panel.
Solar panels with thick-film technology and older models contain relatively thicker layers of silver. It could contain as many as 13 troy ounces of silver. An average solar panel measuring 2 square meters may contain up to 20 grams of silver. (source)
Silver Vs. Copper Content
According to CRU Group analyst Alex Laugharne, “We forecast a slow decline in silver demand from 2020 to 2023 as [photovoltaic or PV] capacity added per year dips, while attempts at silver thrifting in PV panels continue at a diminished rate.”
The silver volume in solar panels is drifting lower in the coming years. Analysts expect industry innovation to continue to lower silver content per cell, outstripping demand from new solar installations.
On the other hand, copper, which is cheaper, is still an abundant resource. It makes as an alternative to silver. Solar power systems can contain approximately 5.5 tons of copper per MW.
You can also recycle the aluminum frame of the old solar panels. However, you must properly dispose of other materials like an electronic waste. It is critical to avoid leakage of toxic chemicals like lead, arsenic, and cadmium that can be hazardous to health.
Can I Mix Old And New Solar Panels?
Theoretically, mixing old and new solar panels is possible for expansion. But it is not practical because solar panels are one of the technologies constantly changing and improving its standard. Old panels may not integrate well with the new panels.
The most practical way is to create two systems, and the process is augmentation, not mixing. The old system continues to exist, and the new system will be built.
Solar panels can withstand outdoor use; however, normal wear and tear may result in bad panels. Bad panels reduce the efficiency in harnessing solar power, or the whole system will fail to work. Over the years, solar panels may degrade and fail.
With the efficiency and cost-effectiveness of solar energy, you may need to repair or replace it. Repairing it can solve the issues and may increase the life span. Replacing it may improve the generating power of the system.
If some solar panels are useless, both old and new ones are still valuable as some materials like silver and copper are in demand. Its salvage value is worthy, but disposing of the other components must be handled carefully. Toxic materials in solar panels are hazardous waste.
The solar panel is an excellent investment while promoting a cleaner energy source.