What Happens to Solar Power When Batteries Are Full? (With Solution)

Renewable energy sources can be a lifesaver, especially when they can be the cheapest form of power. You don’t need to be an environmentalist to realise that having solar power isn’t just a cool option, it’s practically a must-have superpower for your home!

In recent years, solar power has not only become the most sustainable and renewable source of electricity, it’s also one of the best ways to reduce your energy bills. But, it’s crucial to understand how to store this energy efficiently.

Solar power batteries can store the energy created by the generators for later use. But what happens to that power when the batteries reach their capacities? Is there any way to recycle that extra energy to your benefit? Or, does all the clean energy go to waste?

In this article, let’s explore how to redirect the excess energy so that we don’t lose out on its potential usage.

What Happens When Solar Batteries Are Full?

Solar batteries are used to store the energy produced by solar power systems. But when the power generated exceeds its capacity, the battery can’t store anymore. In that case, overcharging can damage the battery.

The process is pretty simple, the charge controller and inverter must step in to handle excess power to reduce the risk as soon as the battery is full. It can be done in three ways: pushing it back to the panels for power loss, back into the grid, and forcing a dump load. Let’s get more into that, shall we?

Push it back to the panels

This is a very straightforward way to deal with excess energy. When the battery reaches its capacity, the extra power will be directed back into the solar panels. Doing so will cause a temporary increase in voltage. The excess energy will be lost and the overall efficiency will be decreased by this method.

Push it back into the grid

If you have a grid-tied solar system, the extra power can be fed back when the battery reaches its capacity. Since you’re supplying electricity to the grid, you may even receive some compensation or credits!

Force a dump load

The third option involves taking on a dump load. When the battery is full, the dump load will divert the excess power to another device. That device absorbs the energy and converts it into heat or another energy form. This approach ensures the power stored in the battery is safe, while the excess energy is being used productively.

How to Tell If Your Solar Batteries Are Fully Charged

So, now you that know how you can deal with the excess energy, let’s get into how you can tell if the battery has reached it’s limit in the first place. Is there any sign or indicator?

There is. 

In fact, there are two ways to find out if your solar power battery is fully charged.

By the solar battery’s built-in indicators

Most solar batteries come with a built-in indicator. It can display the power level directly on the screen, by making a sound, or through other warning systems. In this case, you can just look into the indicator and tell if the battery is full.

By electronic measuring instruments

If your battery doesn’t come with an indicator, don’t worry. Electronic measuring instruments, like voltmeters and multimeters, can be a great help in measuring the exact charge of the battery.

Voltmeter: this instrument measures the potential of a battery. To check the exact charge, connect the voltmeter to the red and black ports of the battery. Make sure the battery hasn’t delivered electricity for the last few hours to get accurate results. 

Multimeter: the name says it all. It’s a comprehensive tool that can measure voltage, current, resistance, and so many things about your battery’s condition. Just like a voltmeter, connect it red and black ports of the batter and check the results on the screen when the numbers are stabilised.

How to Make Use of Excess Solar Power When Batteries Are Full?

If you read this far, you’ve already known that there are only two things you can do with this surplus energy, either push it back and make it a waste, or try to make good use of the power. 

As you all know, energy waste is extremely harmful to the environment. Let’s look at some of the ways you can use that extra energy.


You can use the excess energy to power your  refrigerator. Usually, solar panels are used to generate power for appliances that require immediate power, not continuous. That’s why it’s practical to use this intermittent power to run ice or refrigeration systems.

The Electrical Grid

Once your solar panels have collected enough energy to power your home and charge your battery, you can send the surplus energy to the electrical grid. 

We recommend you use a net meter on the grid that will record your solar energy use and direct back the excess energy to the grid. The best part? You will receive some credits as a homeowner for doing so, which you can use on future bills.

Air Compression

Air compression machines can be a great option to store energy. Smart on-grid solar panel systems can send the excess power to air compression devices, which you can easily use later.


This is a great option, particularly during the winter season. Based on how much extra energy your solar panels generate, you can use it for water and home heating. It will help you enjoy a hot shower whenever you want while also reducing your electricity bills!

What to Do if Your Batteries Regularly Become Full?

Now you’ve learned about quite a few solutions to your full solar battery, you may wonder, what if your battery gets full regularly? While these are the solutions for occasional incidents, you need to take some permanent measures if this happens frequently.

Sell some of your panels

The reason your solar panels are producing excess energy regularly is maybe because you connected too many solar panels. In that case, selling the extra panels will be a smart move. 

Selling some panels will help reduce the energy produced, thus making sure the battery is never full. Besides, it won’t take you much time to sell solar panels since they are always on  high demand. Also, you will be surprised by the profit you can make by selling them.

Get equipped with more or higher capacity batteries or generators

As you’ve already understood, the best way to balance the generator and the storage of the power is to opt for a high-capacity battery or generator. 

Purchasing a high-capacity battery means it will be able to store more power, ensuring that you don’t have to worry about the battery being full or overcharged. 

Do some research on the internet and you will see quite a few good solar battery options, from which you can choose. 

Besides, you can also purchase a high-capacity solar generator that will help store more power. However, it depends on your budget and your requirements for power.


Solar power isn’t just an eco-friendly alternative but a transformative necessity in our evolving energy landscape. However, it can turn into a nuisance if your solar panels continue to produce excess energy and you have no idea what to do.

However, there are a number of ways you can deal with the surplus energy as we’ve already discussed. 

With various options available, it ultimately comes down to your personal preferences. However, to avoid excess energy production, you need to take some precautions, such as choosing a solar system that will take the hard work out of monitoring the battery performance, including additional capacity, and smartly handling the excess energy. 

In the quest for a greener future, understanding how to harness and manage solar energy not only benefits your immediate needs but also plays a role in shaping a global energy landscape that’s eco-friendly and sustainable. So, as the sun continues to shine, let’s harness its power wisely, and make sure every beam adds value to our lives while minimising the environmental impact.


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