If you use an electrical opening system and there is no easy way to manually open your garage door, then you may want to consider investing in a battery backup. The battery backup will ensure your garage door has enough power to operate for a certain period of time after a power outage at your home.
Battery backup garage door openers make it easy for you to be able to get your car out of the garage, even during a power outage. While most people associate power outages with bad weather, which means you really should not be driving anyway, there are some cases where you need to be able to get out of the garage.
For instance, if the power company is working on a transformer near your home, or a line fell down, work/school/other obligations are not going to stop just because of that.
Depending on the circumstance, these power outages may only last a few hours, but they could last days, weeks, or months. Having access to your vehicle to relocate if necessary is critical.
Older battery backups provided enough power to open the door once or twice, which was just enough to get your car out and leave it outside until the power came back on.
Newer models of battery backup garage door openers are said to have enough power to raise and lower the garage door about 20 times before needing a recharge. The batteries are thought to last about three years.