How Long Does It Take to Charge a Solar Generator?

Portable solar generators are an easy way to add additional power to your off-grid setup.

If you don’t plan on charging them, however, you might find yourself powerless just when you need it the most.

Solar generators take between 1.5 to 48 hours to recharge. Several factors impact the amount of time a solar generator takes to charge, including the size of the system’s battery, the size and quantity of solar panels being used as well as the weather conditions that the panels are operating in. 

There are typically three different ways to charge a solar generator.

These methods include:

1. Solar panels
2. Wall charger
3. Car charger

Depending on the model, solar and/or wall charging are the fastest methods to recharge your solar generator.

I’ve gathered four different solar generators together to show you how long each one takes to recharge from solar panels, wall chargers, and car chargers.

Check out their times/specs below.

When it comes to the amount of time it takes to charge a solar generator, there’s no straight answer.

But there are ways to estimate roughly how long it’s going to take for your unit.

Read on to learn more about charging solar generators and how to charge your generator fast. 

Charge Times for Solar Generators

Charging times for solar generators vary from 1.5 to 48 hours. Maximum input power and battery capacity are the two variables that determine solar generator charging times. Some solar generators allow simultaneous solar and wall charging to significantly increase charging speeds.

The caveat with that statement is that off-the-grid solar generator setups vary wildly from person to person.

The amount of solar energy you collect depends on the efficiency of the panels, the charge controller used (PWM vs. MPPT), and the length of the wires from the panels to the battery setup.

To charge a portable solar generator as quickly as possible, you should maximize the amount of energy being collected by the panels and choose a geographical location that allows for optimal sun coverage on your solar panels.

With optimal sunlight and a fast-charging solar generator, you will have a system that can perform for long periods of time off the grid.

I wrote an article going over some of the fastest charging solar generators and highlight their charging times.

I recommend checking it out as these systems set the standard for quick and efficient charging: Top 5 Fastest Charging Solar Generators (Via AC Outlet & Solar Panels).

How Do You Charge a Solar Generator?

A solar generator typically charges from three different sources: solar panels, wall chargers, and car chargers. Wall and car chargers connect to your wall outlet and 12V car port, however, solar panels have various outputs which may require an adapter to connect to the generator’s solar input.

Some portable power stations can even charge from USB-C PD ports as they can discharge and charge with this one port.

An example of this feature can be found in the Rockpals Rockpower 500. You can charge from its wall charger and USB-C PD port at the same time, which drastically speeds up the recharging process.

I own the Rockpower 500 and tested its features out to see if it lived up to its expectations.

My results can be found in my review post here: Rockpals Rockpower 500 Review (Testing, Pricing, and More).

In solar generator systems, the generator consists of two separate systems:

1. The solar panels that collect the solar energy
2. A battery storage system that collects and contains the energy until it can be reused as electricity

The fastest charging method is usually solar charging, however, there are several power stations that have high-powered AC wall chargers.

EcoFlow is the leader in AC charging, as their patented X-Stream technology can charge several of their generators in just over an hour.

You can see the huge differences in AC charging times in my EcoFlow vs. Jackery article, where I compare similar power stations from both companies.

Read this post here for details: EcoFlow vs. Jackery – Full Solar Generator Comparison (With Specs).

Factors That Affect How Long Solar Charging Takes

When it comes to estimating the time it will take to charge a solar system, there are a few general factors to consider: 

1. Power of the solar panels

The more powerful the cells in the solar panel are, the more effectively they can collect and store solar energy.

The strongest solar panels on the market average around 610-615 watts.

The downside to these large solar panels is that many of them are not suited for residential use. 

2. Weather conditions

Different kinds of weather such as rain, snow, and cloud cover can adversely affect how quickly a solar generator will charge up.

This makes the solar generator a poor choice for electrical appliances where consistent energy input is necessary to maintain function, such as a refrigerator.

However, you can combat this with a large solar panel array to compensate for the decrease in solar activity from cloud cover.

3. The angle of the solar panels

Solar panels should be perpendicular to the sun in order to capture the most sun during the day.

Many people using solar panels on their roofs have an advantage here as several homes have angled/tilted rooftops.

For large solar panel setups, the best way to capture the most sunlight is to rotate the panels according to the sun’s location throughout the day.

Although having a rotating mount for solar panels is unnecessary for most homes and RVs, a study done at Universiti Putra Malaysia shows the results and design of a rotating solar panel array used for a flood evacuation center in Malaysia.

You’ll need to consider your circumstances when you’re choosing a solar setup. Some people have a more urgent need for consistent solar energy generation than others.

Questions you should ask to optimize solar charging

Here are just a few of the factors that affect charge times on a portable solar generator: 

• How much amperage is being collected from the solar panels?
• What is the position of the sun in the sky?
• Is there any cloud cover that could reduce the UV exposure of the solar panels?
• What is the geographical latitude of the solar panels? 
• How many hours of sunlight are the solar panels receiving per day?

If you find that one solar generator isn’t generating enough energy in your current solar conditions, it can be due to the following:

• Not enough solar panels
• Improper or inefficient solar panel setup/connection
• Solar generator battery is too small

Improving one or more of the above areas can improve your off-grid setup.

I have an article going into more detail on proper solar panel installation that can help you create or adjust your system for ideal results.

You can find the guide here: Solar Panel Installation – Step-By-Step for Home and RV.

In order to avoid injury and/or damages to your property, it is always best to consult a professional before installing a solar panel array on your home, cabin, or RV.

What to Look For in a Solar Generator

If you’re setting up a new solar generator system, you’ll want to look for the most efficient and effective systems.

There are a few different factors you’ll want to consider when you’re doing comparison shopping for solar generators: 

• Battery capacity: The greater the battery capacity on a solar generator, the more energy it’ll be able to store and distribute to electrical devices. Some high-energy appliances such as refrigerators require a higher wattage of power than other appliances/electronics like ceiling fans, CPAP machines, and lighting.
  
• Weight/portability: Some off-the-grid consumers will be better able to carry a heavier portable solar generator than others, but your carrying capacity should be something to think about when you’re looking at the weight of a solar generator you intend to carry from place to place.
  
• Charge speed: You’ll want to look for a solar generator setup with the fastest charge speed in watts-per-hour that you can afford, but keep in mind that your generator may not be able to charge as quickly when it’s also being used to run appliances simultaneously.
  
• Expandability: Expandability refers to a solar generator setup’s ability to be expanded with additional battery storage. This allows the system to store even more energy when energy collection is most efficient due to ambient weather conditions.

An example of a solar generator with expandable batteries is the Titan by Point Zero Energy.

I recommend reading my analysis of the Titan as it will give you insights into how much power you can generate over long periods of time with additional battery storage: Titan Solar Generator Review – The Best Large Solar Generator?.

Can a Solar Generator Be Used While Charging?

Some solar generators can be used while they are charging. Most manufacturers use the term “simultaneous charge/discharge” within the specifications sections of their product pages to indicate that their system can be used while it is charging.

A solar generator can power appliances while also being used to collect solar energy.

This is typically found in systems with batteries larger than 1,000Wh.

The solar generator achieves this by using incoming solar power to generate electricity, then storing any excess energy collected on top of the energy being used to power the electrical outlet.

Because of the way that energy is stored while a solar generator is being used to output electricity, using it to power a bunch of appliances at once will cause it to gather additional solar power less efficiently. 

How Long Does a Solar Generator Battery Last?

The average solar generator battery lasts for 500 lifecycles to 80% battery capacity. Solar generators with lithium-ion batteries last from 500 to 2,000 lifecycles. Ones with lead-acid batteries last from 300-500 lifecycles. Systems with LiFePO4 batteries last from 1,000 to 6,000+ lifecycles.

As you can see, the lifespan of a solar generator battery depends largely on what type of battery is being used to store electrical energy for the system.

The Bluetti EP500 has one of the longest-lasting batteries because it stores a massive 5,100Wh LiFePO4 battery rated for 6,000+ lifecycles to 80% capacity.

You can find more information on the EP500 in my overview post here: Bluetti EP500 & EP500Pro Review – Longest-Lasting Solar Generators.

What Is a Lifecycle in Batteries?

In solar generator batteries, a “lifecycle” is used to refer to the cycle of a battery being charged to full capacity and discharged of energy again.

All solar generator batteries can be charged up and discharged for hundreds of lifecycles before experiencing any loss of function from old age and use.

However, the best portable power stations can last for thousands of cycles, which significantly adds value over time to the system.

Keep in mind also that cold weather or extreme heat is considered a serious stressor on the lifespan of batteries.

How Long Can a Solar Generator Power a Fridge?

The tricky thing about powering a fridge from a solar generator is that refrigerators require a lot of electricity to run relative to other appliances.

A standard-sized refrigerator can run for around twenty-four hours on a medium-sized (1,000-1,500Wh) solar generator with a full battery.

However, several fridges can run indefinitely if the solar generator has a high enough solar input.

The solar panels can recharge the system while it is using power to run the refrigerator.

I created an entire post dedicated to the best solar generators for refrigerators.

I give examples of full-size refrigerators and match them up with different solar generators to see how long they can run. Check it out here: 3 Best Solar Generators for Your Fridge (With Run Times).

On a lower scale, several different solar generators can be used to power mini-fridges for long periods of time.

The lower power consumption from mini-fridges compared to full-size fridges allows you to use a smaller solar generator as it will not need a large battery.

You can still use a large solar generator for a mini-fridge, but it all depends on how long you need it to run off the grid.

I detail three examples of solar generators that can run mini-fridges in my article here: Can a Solar Generator Power a Mini-Fridge?.

In general, to run a fridge off a solar generator, make sure you have more than enough energy to keep the fridge running no matter what.

Similar: 10 Best Mini-Fridges for Your Off-Grid Cabin

Choose a Good Solar Generator Setup for Efficient Charging

For many off-the-grid home and RV owners, choosing an efficient solar generator setup is rarely a life-or-death situation.

After all, many off-the-grid setups also include some type of fuel-based energy generation system as a backup for their solar collection systems. 

But faced with the fuel shortages of the 21st century and other environmental problems, choosing a solar generator that charges as effectively as possible can help you maintain energy independence when fuel and utilities are inaccessible.

Continue Reading:

• Solar Panel Installation – Step-By-Step for Home and RV
• Are Solar Generators Tax Deductible? (Federal Solar Tax Credit)
• Can Solar Generators Be Used Indoors? (Best Practices)