A recent survey on "consumer behavior and attitudes toward power usage and outages" uncovered some pretty deep and serious worries.
An alarming 84% of respondents registered concern about power outages, with 26% distressed enough to feel vulnerable and unsafe.
So, it's no wonder that among homeowners actively considering a solar system, 70% plan on including a battery.
Well, we've covered how long your solar panels are going to last.
Likewise for the expected lifetime of your solar inverters.
So, given that increasing public concern about power outages is only going to solar battery storage an even more popular option, it's time we turned to the life expectancy of residential solar batteries.
The general facts
If you do choose to add a battery to your solar system, how long it winds up lasting will depend upon several factors.
Generally, however, you can expect a residential solar battery to last somewhere between 5 and 15 years.
That means it's all but certain that any battery installed alongside
your solar system will have to be replaced at least once before your solar panels themselves have reached their 25-to-30-year expected lifetime.
As for specifics, here are the three major factors that are going to determine how long your solar battery is going to last should you choose to include one.
1. Cycle life
A battery's cycle life is just the number of times it can be charged and discharged before losing performance.
But, whether it's designed to be paired with a solar system or for some other purpose entirely, the cycle life of a battery will be one of the main factors determining its lifespan.
The greater your battery's cycle life, of course, the longer it will last.
2. Location
Where a solar battery is located also has a significant impact on its lifespan. A battery that sits outside completely unprotected from the elements is likely to degrade more quickly than one that's sheltered in a garage or some other simpler type of structure.
3. Depth of discharge
You've probably never heard of it, but every solar battery also comes with a rating representing something called its "depth of discharge" (DoD). That's just the percentage of the battery that can be discharged without causing any damage.
Lithium-ion batteries—by far the most common type when it comes to residential solar— have a depth of discharge falling somewhere between 80% and 95%—with 90% being fairly standard.
But don't worry. You won't have to spend time monitoring your solar battery to make sure it stays within the confines of its DoD. Today's "smart batteries" have protective features that prevent them from discharging too much power.
Warranties
As for the kinds of warranties you should look for when shopping for a solar battery, standard lithium-ion batteries used in residential projects typically come with a 10-to-12-year warranty.
Though lead-acid and other less common types of solar batteries have shorter warranties, if you do decide to have a battery installed alongside your solar system, it's overwhelmingly likely to wind up being lithium-ion.