Is It Wise To Charge a Solar Battery With a Generator?

Whether it’s wise to charge a solar battery with a generator is open to debate. While a generator provides an easy and convenient way to charge a solar battery, there are advantages and disadvantages to consider before choosing this option.

If you have an older solar system and need to charge it quickly, charging a solar battery with a generator is a viable option. However, there’s potential damage, as most generators aren’t designed to charge solar batteries.

This article will walk you through the pros and cons of charging a solar battery with a generator, the potential damage that can occur, and tips for doing it safely. Let’s get started.

Does a Generator Damage a Solar Battery?

Although a solar battery can be charged with a generator, there is a potential for damage. Generators run on gasoline or diesel fuel, so they aren’t designed to charge solar batteries; they produce a high-amperage current that could damage the battery.

The voltage of a generator also tends to fluctuate, another factor that can cause damage to a solar battery. For these reasons, it’s vital to ensure the generator you use is capable of producing a steady and consistent voltage, and you should also monitor the battery’s charge level while charging it.

If the charge level gets too high, it could cause damage to the battery and decrease its lifespan.

The Pros of Charging a Solar Battery With a Generator

The primary benefit of using a generator to charge a solar battery is convenience. A generator can quickly and easily recharge the battery, allowing it to be used immediately.

Also, most generators are portable and easy to transport. This makes them ideal for emergencies or when you’re in an area where solar panels are unavailable. Let’s take a look at some other pros of using a generator to charge a solar battery:

Generators provide an immediate power source in emergencies or when solar panels are unavailable.
It’s a quick and efficient way to charge a solar battery.
Generators are easy to transport due to their portability.

The Cons of Charging a Solar Battery With a Generator

Although there are some benefits to using a generator to charge a solar battery, there are also potential drawbacks. The most troubling aspect is the danger of deteriorating the battery because of the large current produced by the generator.

If the voltage is too high, an excessive current will flow into charged batteries, which then causes electrolyte water to decompose and accelerates aging. Also, generators rely on fuel, so you must refuel the generator periodically.

This can become expensive over time and may make charging with a generator impractical. Here are some other cons of using a generator to charge a solar battery:

Generators produce a high-amperage current that can damage the battery.
Generators require fuel, which can become expensive over time.
Generators are loud and may disturb people in the area.
It may not be possible to get a generator in an emergency.

How Does a Generator Damage a Solar Battery?

You must understand how the two work together to understand the potential damage caused by charging a solar battery with a generator. Generators produce a large amount of energy in the form of electrical current.

The generator voltage usually fluctuates, which isn’t ideal for solar batteries. A battery exposed to an excessive current will cause the electrolyte water to decompose and accelerate aging, ultimately decreasing battery life.

It’s also essential to monitor the battery’s charge level while it’s being charged. If the charge level gets too high, it could cause damage to the battery and decrease its lifespan. If the voltage gets too high, the battery may be damaged beyond repair and require a replacement.

What Can You Do To Prevent Generator Damage to Your Solar Battery?

While charging a solar battery with a generator can be convenient in certain situations, it’s crucial to understand the potential damage that can occur. To reduce the risk of damage, there are some steps you can take:

Ensure the generator produces a steady and consistent voltage.
Monitor the battery’s charge level while it’s being charged.
Follow the manufacturer’s instructions carefully.
Use a voltage regulator to ensure the generator produces only a little voltage.

How To Properly Charge a Solar Battery With a Generator

You’ll need a generator with the required voltage to charge your solar batteries. However, it’s important to note that you can’t connect the battery directly to the generator.

You’ll also need an inverter to convert AC power into DC before it can reach and charge the battery.

Follow these steps to ensure safe generator charging of your solar battery:

1. Check the Fluid Levels of the Solar Battery

Maintaining your solar battery and generator efficiently ensures they run at full capacity. Always start by checking the solar battery’s fluid levels. To do so, fill it up to the marked line using distilled water. If you overfill, Spillage might occur, so be careful to leave the right amount.

2. Plug the Inverter Into the Charger Outlet

An inverter regulates the current that goes to the solar battery, and a high current can risk permanent damage to the battery. The inverter’s charger outlet is either labeled with an icon or the word “charge.” You simply need to attach the charger outlet to the inverter and plug it into the generator.

3. Connect the Charger to the Solar Battery

Connect the charger to the battery and inverter. Ensure the cables are secure and don’t move around too much. It’s essential to connect the cables in the correct order; otherwise, you may cause a short circuit and damage your equipment.

4. Plug the Charger Into the Inverter

Connect the charger to the inverter and plug it into the wall outlet. Monitor the charge level throughout the process, as you want it to stay within the recommended level. Unplug the charger once the battery is fully charged and disconnect it from the battery.

Generator Sizing Guide for Portable Solar Systems

Now that you know how to safely charge a solar battery with a generator, selecting the correct size is essential.

A larger generator will provide more power but will be noisier and more expensive. On the other hand, a smaller generator might need more power to charge your solar battery.

Sizing a Generator for Your Solar System

If you need a generator, get one that’s the correct size. Remembering that the generator should be twice the size of an inverter’s continuous output is a good rule. So, if you have a 4,000-watt inverter, go for an 8,000-watt generator.

This is because the generator not only has to power the loads (appliances using energy) but also needs to charge batteries. Calculating your system takes both of these elements into account. If your loads total 4,000 watts and your charger is 60 amps at 48 volts, that totals around 7 kW of continuous power.

Therefore, an 8 kW generator would be the minimum size to provide adequate power to charge the battery bank and power the loads. However, it’s best to opt for one with a bit of extra power, too, as this will ensure you won’t run your generator at total capacity all the time.

Is It Possible To Use a Small Generator To Charge a Solar Battery?

Sometimes, you can power your loads with a smaller 300-watt generator. However, this is not recommended for charging solar batteries as the battery will take much more power than the loads.

Small generators typically don’t have enough power to charge your batteries and may cause potential damage. In short, you can charge a solar battery with a generator, but you must select the correct size and follow the above steps.

Use a sizing guide and choose a generator with the extra power to account for high altitudes or other conditions that could limit its capacity. Doing so will help protect your solar battery and ensure it gets the right power.

Is It Possible To Use a Large Generator To Charge a Solar Battery?

It’s possible to charge a solar battery using a large generator. I recommend using a 600-watt generator or higher to power a 30-amp charger. This will ensure that the generator can handle the charging process without problems.

It should be noted that when utilizing a generator to charge solar batteries or any other type of battery, it’s crucial to ensure the unit provides enough power and can maintain a suitable voltage for optimal performance.

Utilizing large generators for this purpose may result in higher efficiency and better overall charging performance when compared with smaller units.

How To Keep Your Solar Battery in Good Shape

Keeping your solar battery in good shape is imperative for its life and performance. To keep it running smoothly, checking voltage and electrolyte levels regularly is essential.

Sulfate causes around 80% of batteries to fail. This is especially important in flooded batteries as this can prevent sulfation. However, it’s important to note that checking fluid levels only applies to flooded batteries. AGM and gel batteries don’t require checking fluid levels or specific gravity.

Let’s go over some steps you should take to keep your solar battery in good shape.

Check the Fluid Level

Checking the fluid level of your batteries is a simple task that should be done periodically. First, before you start to add fluid, make sure to raise the battery cap and peek inside.

Distilled water should only be added to the designated “fill line” to not expose any metal lead surfaces. It’s advisable to fill the cells sparingly, or some fluid might splash out in an unforeseen situation.

Once complete, the maximum fluid level should be approximately 1/2″ below the cap line. Performing this step will keep your batteries running in top shape.

Check the Charge Level

Properly monitoring your battery’s charge level is vital to maintaining a healthy battery and energy system.

Doing so requires regularly checking the voltage, specific gravity readings, and any other information provided in your manual or by the manufacturer. Suppose your batteries are 6V instead of 12V. In that case, you’ll need to divide the voltages by two — the same rule applies when multiplying the voltages if your system is 24V.

Lack of proper monitoring could cause sulfation damage and reduce performance. Review these factors regularly to keep your battery functioning at its peak state.

How Often Should You Charge Your Solar Battery?

Charging your solar battery is essential to maintain its performance. That being said, it’s important to monitor your battery’s charge level and ensure you charge it with the right amount of power at the right time.

Generally, batteries should be charged every 2-3 months or when the voltage drops below 12.4V, whichever comes first. Check the owner’s manual for specific information, or contact the manufacturer if you have any questions about your battery’s charging requirements.

Clean the Solar Battery

Cleaning your solar battery is a straightforward task that should be done regularly to maintain health. To do this, follow these steps:

Begin by disconnecting the negative lead of your battery.
Use hot water with baking soda or a soft plastic brush to scrub the surface and remove dirt and corrosion buildup.
Use compressed air or a vacuum to remove any remaining debris.
Rinse the surface with clear water.

Doing this will help keep your battery running clean and strong.

Bottom Line

Given solar batteries’ importance in providing you with power, proper care is essential and includes:

Regularly checking fluid levels.
Cleaning the battery surface.
Charging it at the right time with the right amount of power.

Consider using larger generators to maximize performance and efficiency when charging your solar battery. Doing all this can give you peace of mind knowing that your solar battery is functioning properly and keeping you powered up.