With grid outages increasing and the constant drumbeat from lawmakers, news outlets, and policymakers about how unstable our grid is, you might be wondering, should I add a battery or generator to my solar system? The answer as in most situations is “It Depends.”

Tesla Powerwall product

The two main things to consider are what problem are you trying to solve and your budget. Batteries have many advantages over generators such as:

  1. Batteries such as the Tesla Powerwall typically can last 8-12 hours providing power during an outage without the need to go get fuel.
  2. Batteries are quiet. A generator can emit 50 to 100 decibels which can be as loud as a live concert.
  3. Batteries qualify for a 30% federal tax credit to help offset costs.
  4. Batteries run on clean fuel. Batteries charge from the sun when you are producing more energy than your house requires. This excess energy is stored until the sun goes down and then used to get you through the night.
  5. Batteries save you money. Several utilities and Retail Energy Providers (REPs) charge you for any energy that you pull from the grid at night. A battery provides energy arbitrage by allowing you to store your excess energy during the day and use it at night.
  6. Batteries are safer and cleaner than generators. Generators run on either diesel or natural gas. Both can emit dangerous fumes and are not good for breathing or the environment.
  7. Most batteries can turn on now instantaneously keeping all of those clocks working without having to be reset. Most generators take 15-60 seconds to turn on.
  8. Batteries keep your solar system running in case of an outage. A solar system without battery backup is required by the electric code to shut down within seconds. If there is a battery then the solar system will disconnect from the grid and go into islanding mode which allows the system to continue running in an outage.
  9. Batteries have a longer warranty than most generators. Most batteries have at least a 10-year warranty compared to a 3-5 year warranty on a generator.

Emergency Backup Power on exterior of home

So why would you buy a generator?

  1. A generator can run a whole house for longer assuming you have enough fuel.
  2. A generator can be less expensive initially to purchase. The main difference between a generator and a battery is that batteries store energy and allow you to use it later while a generator produces energy. Both have their places but as you can see there are many things to consider when deciding which one is better for your circumstances.

Need assistance or support in deciding which option is right for you? Contact us today.