Unfortunately for your solar electric system, the sun sets every evening. Homeowners who want to be off the grid or protect against blackouts may connect a battery bank to their solar system to store electricity for nighttime and emergency uses. There are, however, important variables that should be taken into account (pun intended) when considering a battery bank.
- Maintenance. Traditional wet cell batteries will require a fairly rigid maintenance schedule. They will need to be topped off (water), consistently protected from the elements, and properly vented. These are just a few tasks, and much more must be kept in mind in order to avoid potentially dangerous repercussions.
- Recharge. Your solar panels will take care of charging the batteries. It is important to make sure that each battery in the bank is properly wired and receiving a charge. Many batteries cannot recover from deep discharge and would need to be replaced. Overcharging is also a potential problem. Charge regulators are necessary for battery banks as well. There is a strong argument for gel cell or AGM batteries as an answer to many of these issues. These batteries are much less volatile than wet cells, can withstand 100% discharge, and are maintenance-free.
- Recycling. Taking care of spent batteries is an inevitability, and one to be taken seriously. Traditional batteries can be very dangerous and extremely harmful to the environment. It is important to find and follow battery disposal instructions in your area. Again, gel cell batteries are often recommended because they have no special disposal procedure and are fully recyclable.
For off-the-grid solar installations, a battery bank is an obvious must-have. They are also fairly common for more urban installations, either because a homeowner wants off the grid or as a backup should the grid fail. Battery banks are, however, often discouraged by system designers and installers for a few reasons. First, they usually require maintenance and safety considerations. Second, they are no guarantee of sustained power in an outage and can take up a lot of space. Finally, battery banks can defeat the purpose of net metering, which can make a grid-connected solar system a lucrative investment.
So, battery banked solar systems are somewhat rare in urban or suburban applications because of costs and the lure of net metering or feed-in tariffs. They are, however, a valuable safety net for homeowners against the ever increasing load on the electrical grid. Furthermore, technological advancements (such as gel cell or AGM) are improving the battery bank resume, so to speak. Such innovations are lessening maintenance needs while increasing function, efficiency, and safety.
To find out more about solar energy for your home, visit CalFinder Solar’s “Ask the Solar Pros.” Then, contact us to receive free estimates and referrals to the most qualified solar installers available in your area.