Project Description

If you want power during an outage or you want to run tools and appliances off-grid (in a remote cabin, for example), you’ll need a power inverter to convert DC battery power into AC power.

Anyone who needs to run appliances and devices like drills, computers, electric lights, hot plates, microwave ovens, phone charges, refrigerators and more with off-grid power will require a power inverter. And while an automobile or marine battery can be used with a smaller power inverter (for more limited applications), it’s preferable to go with a more robust deep-cycle battery for extended off-grid use and recharges- as well as powering several devices at the same time.

Selecting the Right Power Inverter Size

Once an inverter is connected to a battery, you can simply plug your AC appliances into the inverter. Many modern inverters also come with USB ports, which let you plug phones, tablets and other USB-powered electronics directly into the inverter.

If you only want to run a few lights, tools or just charge essentials (like a phone or water purifier) and only need a limited amount of power for a limited amount of time, a smaller power inverter like our 600 Watt Pure Sine Inverter 12 Volt To 120 VAC or the 1000 Watt Pure Sine Inverter 12 Vdc To 120 VAC should do the trick.

Of course, for off-grid living or extended energy use for homes and offices, we carry much larger, energy-efficient inverters capable of providing you with access to 4000, 6000 and even 12,000 watts of continuous power (plus 36,000 watts of 20-second surge protection). A good example of one of these kinds of inverters is our workhorse, the 12,000-Watt Pure Sine Inverter Charger 48Vdc/240 VAC Input To 120/240 VAC Split Phase Output Inverter.

Calculating How Long a Power Inverter Can Run on Batteries

Selecting the right inverter should be based on how many appliances and devices you’ll need to run during a power outage (aka your power draw). This information is important to know, letting you choose a suitable inverter with enough wattage capacity- ideally a bit more than you think you’ll need to be on the safe side- capable of handling the collective wattage requirements for all of the devices you plan on powering during an outage.

You may also need a battery bank to meet your off-grid/emergency power usage needs. This simple equation will help you calculate how much battery power you’ll need for your appropriately-sized inverter, based on your estimated power draw:

Battery Bank Size Estimate:
Uninterrupted hours of power (needed) x watts = total watts/DC volts=amps (needed)
For example, if you need three hours of continuous, uninterrupted power for appliances and devices that require 2000 watts per hour (in total), your calculation would look like this:
3 (hours) x 2000 watts = 6000 watts
6000 watts/12 volts DC = 500 amps

At The Inverter Store, we advise clients or anyone who asks to never fully deplete their batteries. Instead, we recommend only a 50% depth of discharge whenever possible. For real-world power inverter and battery applications, this means dividing calculated power usage time in half.

How Long Can You Run a Power Inverter on a Battery?

This depends on several variable factors, including how many 12-volt deep cycle batteries (along with their amp-hour or Ah rating) are in your battery bank, the size of your inverter (in watts), how many devices you’ll need to run (total watts), plus how long you plan on relying on continuous, uninterrupted power backup.

Let Us Help

If math isn’t your strong suit or you’re not sure how much emergency power you need, you can get in touch with the experienced technicians at The Inverter Store. We’ll help you sort out your backup power inverter needs.

* You can also get a total watt estimate for the different devices you plan on powering with your inverter and batteries.