Should I Cover Solar Panels When Not in Use?

If you’re doing maintenance or going away for a while you might worry about your solar panels.

You’re probably thinking about covering them over to stop electricity production and protect them from damage.

Well, it is not essential to cover solar panels when not in use.

In fact, it can actually be a big disadvantage to try to switch your equipment off when you’re not drawing any power.

Let’s take a look at the concerns involved with covering solar panels. Plus when it’s a good idea and when it’s a bad idea.


Why You Don’t Need to Cover a Solar Panel When Not in Use

Solar panel systems are designed to be perfectly safe even when not in use.

You should not have any problems with ‘too much sunlight’ or excess energy creation.

In the main there are two different types of solar systems, grid-tie and off-grid. They operate a little differently so I will explain what happens to each when not being used.


Off-Grid System

Off-grid solar panels systems are what you find when there is no access to mains electricity. 

You will find them on vehicles like RVs and boats, adding to this they are used on remote buildings.

There are three main components in the system, solar panel, charge controller, and battery.

You might be concerned that an unused off-grid solar panel will over charge your batteries if you don’t use any energy.

The job of the charge controller is to protect your batteries from overcharging. It automatically senses the energy levels of a battery and will stop sending energy when full.

So what happens to the electricity created by the solar panel? 

Well, nothing happens. The charge controller will switch off the current just like a switch. No more electricity is then being generated.

If you have connected your solar panel directly to your battery then you should be very careful. Don’t leave your solar panel to endlessly charge your battery as it will overcharge and explode. Rather than cover your solar panels, you should add a solar charge controller.


Grid-Tie System

A grid-tie solar panels system does not have a set of batteries that can be overcharged.

The electricity you generate flows directly into your inverter and into your house to run your appliances.

But what happens when you don’t use this electricity?

The beauty of this system is that excess energy is sent to the main grid for other people to use.

Then you are credited by your electricity company for your electricity generation. So you will be making money.

If you are going away for a while, you can simply leave your solar panels to produce electricity for the main grid and make money.

So why would you ever want to cover them over? 


Reasons to Cover Your Solar Panels

Despite the general rule, you still might find a reason to cover your solar panels. 

Protect from Bad Weather

If you know there is a storm on the way and you’re not getting much sunlight then a protective cover could be comforting.

Solar panels are designed to be durable outdoor pieces of equipment but they are still susceptible to damage.

Normal rain, snow, or wind won’t pose any threat to your panels. But if you are expecting large hailstones then you might consider extra defenses.

Aggressive hail storms have been known to cause serious damage in certain areas of the world. 

Solar panels are built to withstand impacts from hailstones up to 1-inch in diameter. So if you think there is risk of anything larger then it’s time to cover up.


During Maintenance

You might feel more comfortable working on your equipment with the solar cells covered, particularly any wiring maintenance.

This will completely stop any electricity production and avoid risk of electrocution. 

To be honest, there is no risk of shock from a 12V panel as the voltage is too low for a human to feel. But for larger systems, it is prudent to cover panels for your own safety.

The real risk of electric shock comes when working on the controller and inverter where voltages are higher than that of a single panel. 

If you’re worried about electricity while wiring your inverter then you can cover the panels to kill the current.


Keep Clean

A friend of mine who uses solar panels on his boat often covers them over when not in use.

This is simply to keep them clean and increase their longevity.

Not many of us enjoy cleaning so a cover will keep dirt and grime off your equipment. 

It will stop any dust build up or annoying bird excrement getting onto the surface.

And remember, for maximum efficiency a solar panel must be completely clean!


Reasons Not to Cover Your Solar Panels

If you’ve read this far you should already have an idea whether you need to cover your solar panels or not.  If you’re still not quite sure, here are the clear reasons you don’t need to bother.

Excess Energy Not a Problem

If your equipment is wired up correctly you should never have an issue with generating too much electricity.

Even if you are not drawing any power, you will have safety protections in place to stop your batteries overcharging. This is why it’s always essential to have a charge controller installed on all off-grid systems.

Adding to this, your home solar system will be grid-tied so excess energy flows onto the main grid. This is a big benefit as you will earn money for your electricity production.


Durable Build Quality

Solar panels are built to resist all types of weather. 

They have waterproofing, anti-rust aluminum frames, and reinforced tempered glass.

Even when it is snowing or hailing, your panels should stand up to the test.

In fact, they will happily sit on a rooftop for decades, even 40 years or more!

In most locations around the world, there is no need to protect them from bad weather.


Should You Unplug an Unused Solar Panel?

There is no reason to unplug an unused solar panel. 

If you are worried about batteries overcharging, then ensure you use a solar charge controller to avoid this issue. The charge controller automatically senses a fully charged battery and stops electricity production.

You can unplug an unused solar panel if you want to although it will make little difference in a correctly wired system.


Is it Ok to Leave a Solar Panel Disconnected? 

Yes, it is perfectly safe to leave a solar panel disconnected. They won’t be able to produce an electric current as the circuit will be incomplete.

As most solar panels are 12V or 24V you won’t get an electric shock if you accidentally touch a wire as the voltage is too low.

There is also no risk of any damage to a disconnected solar panel. It won’t produce any energy or voltage. You might notice it gets hot like the hood of a car as the sun’s energy is no longer being converted into electricity.


Final Words on Covering Solar Panels

99% of the time there is no need to cover solar panels.

On rare occasions, you might want to add a protective cover when you are worried about bad weather, maintenance, or excess dirt.

Whether you have an off-grid or grid-tie solar system, if it is connected correctly there is no risk from excess energy production. 

Charge controllers should be used to protect batteries, while home panels can send extra electricity to the main grid.

In fact, by covering grid-tie solar panels you will stop yourself from earning any credit for your efforts.