Efficient solar battery storage is essential if you wish to remain off grid and run electrical appliances in your home on cloudy overcast days and at night when photovoltaic (PV) panels cannot generate sufficient electrical power. That's because photovoltaic panels can only generate electricity when they're directly exposed to sunlight. So, we need to have a practical backup power plan in place to maintain today's busy lifestyles. This article explains what is needed.
A solar battery storage system usually takes the form of an array or
bank of deep cycle batteries kept on sturdy shelving in a vented, secure
location like the corner of a dry basement or a converted storage room.
Connected between your PV panels and the batteries, you'll need a battery charge controller to help regulate the flow of electricity to and from your bank of solar storage batteries and maximize their service life.
The size of the solar storage battery bank needed will depend on the size of your home or building and its daily power requirements, and the size of your installed PV system. You will need to determine your electricity needs by averaging the previous year's utility bills. Calculations of this sort will help determine your battery needs.
Storage batteries are expensive. When installing solar power, there is an initial cost quoted for the system, so be sure that all the components you need are covered in the estimate for the best pricing.
Some installers quote a price that includes your solar power inverter, your solar storage batteries, and your charge controller, but this isn't always the case. Make sure everything is included to avoid surprises.
You might not need a battery backup system in place. It all depends on whether you want to install a fully operational off grid PV system, or just a partial one.
For instance, you could remain grid tied and simply connect automatically to the power grid after sundown and use electricity from the local power company as your backup power source.
Or, if you plan to sell your generated surplus power back to the electrical utility by taking advantage of a Feed-in Tariff (FIT) program, you won't need backup power storage at all.
Storage batteries would be optional in such cases, though you might wish to have a standby generator connected for those unexpected times when there are prolonged power outages and your battery charge is low.
Good planning will help determine whether a solar battery storage system will be effective for meeting the electrical needs of your household. The following articles offer additional information to help you in your early planning:
Solar Power Batteries - What Are Deep Cycle Batteries?
How to Protect Your Batteries with a Solar Charge Controller
More About Solar Power Backup Systems