what size battery for generac 24kw generator

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A reliable standby generator is a great investment for homeowners who want to ensure uninterrupted power supply during an outage.

However, choosing the right battery size for your Generac 24kW generator can be daunting.

In this blog post, we’ll guide you through the process of selecting the appropriate battery size that will keep your generator running smoothly and efficiently.

what size battery for generac 24kw generator

For the Generac 24kW generator, the recommended battery size is a 12-volt Group 26R, wet cell battery.

This battery is suitable for all air-cooled standby generators and provides reliable starting power for your generator.

Here is a table summarizing the recommended battery specifications for the Generac 24kW generator:

Model	Battery Size	CCA (Cold Cranking Amps) Range
Generac 24kW Air-Cooled	Group 51 or 51R	500-625
Generac 24kW Liquid-Cooled	Group 31 or 31R	800-1000

How to Calculate the Correct Battery Size for Your Generator

Calculating the correct battery size for your generator is essential.  Just follow the below steps,

Determine the Load Requirement

First, you need to determine the total load requirement that your generator needs to power.

You can do this by adding up the wattage ratings of all the appliances and devices that you plan to run simultaneously.

Determine the Runtime

Once you have determined the total load requirement, you need to determine the runtime that you need from your generator.

This depends on the duration of the power outage or the time you plan to use your generator.

Determine the Efficiency of Your Generator

You need to determine the efficiency of your generator. This is important because it will help you calculate the amount of power to provide during the runtime.

Calculate the Battery Capacity

Using the load requirement, runtime, and generator efficiency, you can calculate the battery capacity needed for your generator.

You can use the following formula to calculate the battery capacity:

Battery capacity (in amp-hours) = (total load requirement x total runtime) ÷ battery voltage x battery efficiency

Consider the Temperature and Depth of Discharge

It is important to consider the temperature and depth of discharge when selecting a battery for your generator.

Batteries have a lower capacity in cold temperatures, so you need to select a larger battery.

Discharging a battery below a certain level can decrease its lifespan, so select a battery with an appropriate depth of discharge.

Choose the Right Type of Battery

You need to choose the right type of battery for your generator.

There are a few types of batteries and each type has its own pros and cons, so choose the best one that fits your needs.

Factors to Consider When Choosing a Battery for Your Generator

There are several factors to consider when selecting a battery for your generator.

Battery Type: 

There are different types of batteries, including lead-acid, AGM (absorbent glass mat), and lithium-ion.

Lead-acid batteries are the most common and affordable option, while AGM batteries offer improved performance and durability.

Lithium-ion batteries are more expensive but offer the longest lifespan and faster charging.

Battery Size and Capacity: 

The battery’s size and capacity should match the requirements of your generator.

The battery should have enough capacity to start the generator and provide sufficient power for its intended use.

Refer to the generator’s owner’s manual or consult with a dealer to determine the appropriate battery size and capacity.

Cold Cranking Amps (CCA): 

CCA is a measure of the battery’s ability to deliver power in cold temperatures. The higher the CCA rating, the better the battery will perform in cold weather.

Maintenance Requirements: 

Some batteries require more maintenance than others.

Consider the battery’s maintenance requirements and ensure you are willing and able to perform the necessary maintenance tasks.

Cost: 

The cost of the battery is also an important consideration. While it can be tempting to choose the cheapest option, balance cost with performance and durability.

The Best Types of Batteries for Generac 24kW Generators

There are different types of batteries available for Generac 24kW generators, each with its own advantages and disadvantages.

Here are some of the best battery options to consider:

Lead-Acid Batteries: 

Lead-acid batteries are the most common and affordable option. They are reliable and can provide enough power for most generator applications.

However, they require regular maintenance and have a shorter lifespan compared to other battery types.

AGM Batteries: 

AGM (Absorbent Glass Mat) batteries are more expensive than lead-acid batteries, but they offer better performance and durability.

They require less maintenance, have a longer lifespan, and can handle deep discharges without losing capacity.

AGM batteries are a good choice for frequent generator use or applications that require high power output.

Lithium-Ion Batteries: 

Lithium-ion batteries offer the longest lifespan, faster charging times, and lightweight portability.

They are more efficient than lead-acid batteries and handle high discharge rates. Lithium-ion batteries are a good choice for frequent generator use or applications.

Maintenance Tips for Your Generator’s Battery

Here are some maintenance tips to help prolong the lifespan of your generator’s battery:

Keep the Battery Clean: 

Regularly inspect the battery for any signs of dirt, debris, or corrosion.

Clean the battery terminals and cables using a wire brush and a mixture of baking soda and water to prevent corrosion buildup.

Check the Water Levels: 

If you have a lead-acid battery, check the water levels regularly and add distilled water as necessary.

Be careful not to overfill the cells, as this can cause electrolyte overflow and damage the battery.

Perform Load Tests: 

Periodically perform load tests on the battery to ensure it can handle the generator’s power demands.

Load testing involves simulating a power outage and verifying that the battery can start the generator and provide sufficient power.

Charge the Battery: 

Keep the battery charged to prevent sulfation, a process that occurs when lead-acid batteries are left discharged for extended periods.

Use a battery charger or a trickle charger to keep the battery charged.

Replace the Battery as Needed: 

Most generator batteries have a lifespan of three to five years.

If the battery is not holding a charge, is damaged, or not providing enough power for the generator, replace it.

How to Replace Your Generator’s Battery

Here are some steps to follow to replace your generator’s battery:

Turn off the Generator: 

Before replacing the battery, turn off the generator and disconnect it from any power source.

Locate the Battery: 

The battery is typically located near the generator’s engine. Refer to the owner’s manual or consult with a dealer to locate the battery.

Remove the Old Battery: 

Carefully remove the old battery by disconnecting the cables from the terminals.

Be sure to remove the negative cable first, then the positive cable. Remove any brackets or bolts holding the battery in place.

Prepare the New Battery: 

Match the specifications of the old battery to the new battery. Clean the battery terminals and cables with a wire brush and a mixture of baking soda and water.

Connect the positive cable to the positive terminal, and the negative cable to the negative terminal.

Secure the New Battery: 

Install the new battery in the same location as the old battery, securing it with brackets or bolts if necessary.

Test the New Battery: 

Turn on the generator and test the new battery by performing a load test.

This involves simulating a power outage and verifying that the battery can start the generator and provide sufficient power.

FAQs

Conclusion

Selecting the right battery size for your Generac 24kW generator is essential for optimal performance and longevity.

The size of the battery depends on various factors, like load requirement, runtime, efficiency, and temperature.

Consult the manufacturer’s recommendations or a professional to determine the best battery size and type for your generator, as well as to ensure proper maintenance and replacement when necessary.

Regular inspection and maintenance of the battery can prevent issues and ensure reliable performance during power outages.