How Many Batteries for a 3000-watt Inverter

A 3000-watt inverter is a powerful device that can be used to power a variety of electrical appliances in an off-grid home.  However, the number of appliances it can run and the period of time it can run them is pegged on the battery capacity. 

In this article, we discuss what you can run from a 3000-watt inverter and choose the right battery size to run these appliances. 

The capacity and voltage of the battery are crucial factors to consider when choosing a battery for your inverter. A high-capacity battery offers increased run time and allows you to use higher-wattage appliances.

What Can You Run Off a 3000-watt Inverter

With a 3000-watt continuous power output and a 9000-watt surge rating a 3000-watt inverter can power multiple high-wattage appliances. This includes appliances such as a 500-watt refrigerator, 1500-watt hair dryers, and a 1000-watt microwave (at the same time). 

Household appliances: It can power household appliances such as washing machines, air conditioners, air fryers, and space heaters. 

Power tools: It can run power tools such as circular saws, drills, and angle grinders.

Electronics: It can power electronics such as laptops, televisions, and gaming consoles.

While the 3000-watt inverter can run all the devices listed above It’s important to note that the specific devices that can be powered at the same may vary. 

This is based on their power consumption and the inverter’s efficiency and it still cannot go over 3000-watt continuously. For instance, you cannot run a space heater, circular saw, and hair dryer at the same time and this can cause the inverter to shut down. 

What Battery Size for a 3000-watt Inverter

When it comes to selecting a battery for a 3000-watt inverter, there are several factors to consider, such as the number of devices connected, and the length of time you want to use them. 

In this instance, we assume you using the whole 3000-watt available. 

How Many Amps Does a 3000-watt Inverter Draw?

To find the size of the battery, you divide the watts by the voltage. 

For a 12v system, you’ll need 

3000/12 = 250 Amps 

A 12-volt system should have a battery that can safely provide up to 166.67 amps of current. 

For a 24v Inverter, you’ll need 

3000/24 = 125 Amps

For a 48v Inverter, you’ll need 

3000/48 = 62.5 Amps

A 24-volt system should have a battery capable of providing up to 83.33 amps of current per hour. We recommend you use a 24v system as the amp draw will be more manageable than pulling 250 amps. 125 amps is still high and you will need very thick wiring. A 36V or 48V is recommended if you using high-wattage appliances over a long period of time. 

How Battery Capacity for a 3000-watt Inverter

We have determined the number of amps the Inverter will be drawing. So let’s find out the capacity. With over 80 amps draw you will need quite a big battery and it will cause huge losses in power due to heat.  Deep cycle Batteries are recommended to be discharged at 20% of their capacity each hour.  

So you will need a 400Ah 24v battery deep cycle battery. This is when you continuously power 3000 watts with the Inverter. This battery will last 5 hours with the Inverter. 

Time Power Requirements (Watts)Amps DrawBattery (24v)
1 hr300083400Ah
30 minutes150041200Ah
15 minutes75011100Ah

If you have the required appliances, you can calculate the required battery capacity based on the actual power consumption of your appliances. 

A Lithium Iron Phosphate battery has a bigger C rating and is much more forgiving when pulling huge amps. 

With a LiFePO4 battery, you can pull as much as 50% of its capacity. This means you can power your high-wattage appliances intermittently while powering other small devices with the Inverter.  So it is possible to use a 200Ah 24V LiFePO4 battery or two 100Ah 12V batteries wired in series?  With a lead acid battery, we would recommend a 400 24v battery or two 12v 200Ah batteries wired in series as the minimum. 


In conclusion, selecting the right battery for a 3000-watt inverter is essential to ensure that you have reliable power for your electrical devices. The choice of battery will depend on various factors such as the inverter’s efficiency, the number of devices connected, and the length of time you want to use them. 

As we have discussed, a deep cycle battery with a capacity of at least 400Ah is generally recommended for a 3000-watt inverter. However, it’s important to consult the manufacturer’s recommendations for the specific battery size and type to ensure optimal performance and longevity.

With the right battery, your 3000-watt inverter can power a range of devices, from household appliances to electronics and lighting systems

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