Home batteries

How does a solar battery work


March 30, 2021 | 4min read

A solar battery stores electricity generated during the day by a home solar system for later use. The amount of power that a solar battery can provide is measured in kilowatt-hours. A kilowatt-hour is a steady stream of 1,000 watts of electricity delivered in one hour. Home solar batteries store a lot more than one kilowatt-hour, and some brands such as the Tesla Powerwall* can be “stacked” to provide as many kilowatt-hours of power that you need.

*Always check with the manufacturer’s specifications to determine battery integration requirements and/or limitations.

Solar battery basics

When your solar system is producing electricity, your home has top priority to that power. Any excess power produced normally is sent to the grid. But when you have batteries, those batteries have priority over the grid, so your solar system will charge them before it sends any power to the grid.

All batteries store DC power, when that power is needed, an inverter converts it to AC power at the voltage needed by your home. Some home batteries are known as AC batteries because they contain an inverter that converts the power. Other batteries are called DC batteries because they depend on an external inverter to convert the power they produce.

How to use solar batteries the wrong way

Solar batteries can be prematurely worn out if you use them improperly. You normally don’t want to charge your batteries to more than 80% of their capacity because that causes them to wear faster. Likewise, you want to avoid using up all of your batteries’ charge because that also causes premature wear. You also want to avoid huge current spikes because those also cause premature wear.

How to use solar batteries the right way

You want to install more battery capacity than you need. This way, you can avoid charging them all the way and avoid discharging them all the way. Having a large-capacity battery system provides enough power to handle current spikes.

The smart way to use batteries is to spread out your power demands so you don’t require the batteries to provide a lot of power at the same time. You can do this by limiting the number of appliances you are using at the same time. Using batteries with a smart home system is a good idea because the system can manage your power demand for you.

Estimate your power usage

Your utility bill can give you a pretty good idea of how much power you need. If your utility bill shows how much power you use by the hour, then base your estimate on the hours that you plan to draw power from your batteries. If you are planning to use your batteries for backup power, then you’ll want to estimate how much power it would take to get you through the night. Once you’ve estimated your power usage, then you can choose a battery system that can meet your needs. Remember that you’ll want a system that can provide more power than your estimated needs. The extra capacity will also help if you have an emergency that causes you to need more power than you normally use.

When you will want to use battery power

Time-of-use (TOU) billing. If your home is on a TOU plan, the time of day when you use electricity determines how much you pay for it. You will want your batteries to power your home during peak rate hours. For California homeowners, those hours are usually from 4 PM to 9 PM. Blackouts: In blackouts, you’ll want to have enough additional power to make it to bedtime, and to provide any additional power to devices such as medical devices that need to run through the night. During the day, your home will be powered by your solar panels, any surplus power will be used to recharge your batteries. Because of this, you will want to make sure not to use all the power your solar system is producing, leave some for your batteries!

Freedom Forever installs solar batteries

Whether you are choosing to go solar with batteries, or want to add batteries to your existing solar, Freedom has you covered. Contact us and we’ll put you in touch with one of our independent authorized dealers in your area. They will help you choose the right battery system for your needs.

Ready to go solar? Call us at 800-685-1850 or click below to get started