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Are your solar panels no longer producing as much energy as before? Or has output completely dropped to zero? Renewable energy systems are complex and there are several reasons this could be happening.
A faulty inverter or obstruction can prevent solar panels from running. If the solar panels are years old, dirt could have built up or there could be physical damage.
Before you call for professional assistance, let’s take a look at the reasons why this could be happening. You might be able to fix the problem yourself, or at least provide the technician important information.
A damaged inverter is one of the most common reasons why solar panel systems suddenly stop working. If energy production drops or stops, the inverter is the first place to look.
Solar panels generate direct current (DC). An inverter transforms solar DC into alternating current (AC) so household appliances can work.
Inverters usually have 10-15 year warranties. If you have a quality one like Renogy 3000W it should still work even after the warranty expires.
There are many reasons why an inverter can malfunction. Some of them I list below.
Overloading. Inverters have a limited capacity stated in watts. If you load it to the maximum all the time or try to exceed it, this can cause permanent damage.
Overheating. If the inverter is overloaded or runs at a very high temperature, its circuits could overheat. This problem affects most household electronics and solar inverters are no exception.
Hardware failure. Inverters are complex machines, and if one part malfunctions, it can shut the entire solar panel system down.
Common causes of inverter hardware failure are:
- Frayed wires
- Damaged capacitors
- Dust and debris blockage
Inverters often display error codes, and you can use them to diagnose and fix the unit.
If your inverter is still under warranty, fixing it won’t be a problem. If the warranty has expired, let a professional tech look into it. Solar inverters are delicate pieces of hardware and it’s best to let experts repair it.
If you have a solar inverter at home, always keep the manual close by. You never know when an error code might appear and the info there can be of help.
Solar Panel Debris
Solar panels are exposed to dirt, dust, debris, bird droppings, etc. If your solar panels have been on the roof for years and you notice a gradual decrease in output, it could be due to debris.
If you are using a string inverter, all the solar panels are connected to it. This means that if one panel malfunctions or gets shaded by debris, it will affect the entire array.
Debris prevent solar panels from getting light, so there is little energy to convert. You or the solar installer has to go up the roof to remove the debris.
Solar Panel Physical Damage
While cleaning your solar panels, it’s a good idea to look for signs of physical damage.
Micro cracks are almost invisible to the naked eye, but professionals can see these with special equipment. Depending on the damage, they might be able to repair the panel or suggest replacing it.
Snail trails are brownish marks that can appear on solar panels. It is often a manufacturing defect and leads to oxidation. These solar panels usually have to be replaced.
Any sort of physical damage, including the PID effect, are difficult to repair, so it is best to let the installer examine it.
Broken Circuit Breakers
Solar panels need circuit breakers to run properly. If these are faulty, output could drop or the system can stop functioning.
If your solar panels are not working, check the circuit breaker box. Some switches might have been turned off or broken.
If your solar panels are tied to the grid, switch to regular electricity. If power flows, then the problem is with the solar panels, inverter or their circuits. You’ll have to call the solar installer to take a look at it.
No Damage at All
Solar panels need sunlight to produce energy. So it’s natural for production to drop during winter.
If you notice a sudden drop in output during the cold season, it’s likely natural and not due to any damage.
If your area gets heavy snowfall, I recommend cleaning the solar panels after winter. Some snow or debris might be left on the roof and affect the solar panels’ performance.
How to Fix Solar Panels with Zero Output
If the output suddenly drops to zero, check the inverter. It is usually the first component in solar panel systems that gets damaged.
If you are off the grid or have solar batteries like the Eco Worthy lithium 2-pack, check the charge controller. This device prevents the batteries from being overloaded by the solar panels.
A broken charge controller or inverter can cause the system to shut down completely. Fix or replace them depending on its condition.
If both are working, the issue is with the solar panels themselves. This is a job for the solar installer since repair work on the roof is risky.
How to Fix Solar Panel Low Power
Solar panels that produce less power than they are capable of happens often. Fortunately there are ways to fix this.
Solar panels must be obstruction-free to work. If a tree or debris blocks the panel, it will hamper production.
If your system uses a string inverter, a single shaded solar panel is going to slow the entire array. You can fix by removing the shade. You can install power optimizers so when one solar panel goes down, it won’t affect the others.
A single frayed, loose or faulty wire can slow down a solar panel system. If you have a battery bank with a charge controller, check the cable connections there.
This might come as a surprise, but solar panels do not like intense heat. Solar panels provide the best results at 77 F (25 C) or thereabouts.
The higher the temperature, the lower the voltage. As the voltage goes down, output drops too.
If your solar panel production drops when the temperature rises, it’s to be expected. Temperatures fluctuate so when it goes to the low 80s and below, the output will increase. If temperature goes up, voltage goes down.
But if the drops become frequent, the best solution is to add more solar panels. It also helps if there is airflow under each one.
Defective Solar Panels
With 25-30 year warranties, solar panels are built to last. But extreme weather, lack of maintenance or poor workmanship can cause damage.
Delamination means laminated solar panel parts have come apart. This allows moisture to seep into the panel and damage the components.
Hotspots usually show up when there are micro cracks on the panel and cause voltage levels and output to go down.
Hotspots often appear on old solar panels. If you suspect this is causing the problem, contact the installer.
Aging and Natural Degradation
If your solar panels are more than 25 years old, it is normal for performance to dip. High quality solar panels can last 30 years, but even before that, expect degradation to happen, albeit slowly.
Solar panels are exposed to dust, dirt, UV rays, hail, snow, humidity etc. All of these will take their toll on even the most durable materials.
The only solution is to replace the solar panels. With a 25 or 30 year warranty, the system has already paid for itself and saved you thousands of dollars.
How to Make Solar Panels Last Longer
Apply protective coating LNK on solar panels. It is a simple but efficient way to protect them from the elements.
Regular maintenance is the most important thing you can do. Solar panels should be inspected at least once a year for damages and cleaning.
The best time to perform maintenance is after winter. You or a professional technician can clean the panels and check for signs of damage.
A solar panel monitoring system detects problems before they can spread. Most inverters have this function, but dedicated monitoring devices are also available.
Install hail guards to safeguard the system not just from hail but other debris. I also recommend surge protectors as protection against voltage issues.
I am an advocate of solar power. Through portablesolarexpert.com I want to share with all of you what I have learned and cotinue to learn about renewable energy.