Energy Support

Powerwall vs. Backup Generator

Be prepared for the next storm or power outage with seamless backup protection from Powerwall while also reducing your electricity bills and earning money by participating in grid services. Explore the following to help you understand and decide on a backup solution for your home:

What is Powerwall

Powerwall is Tesla’s fully integrated, rechargeable home battery that stores energy daily from solar or the grid to back up your entire home during an outage. When a power outage occurs, Powerwall automatically detects the outage and instantly powers your home with stored backup energy. If a storm is forecast, Storm Watch automatically charges your Powerwall to 100% to ensure you are prepared.

Powerwall can be installed indoors or outdoors, wall-mounted or floor-mounted, paired with solar or without and operates in both very cold and hot temperatures.

What is a Backup Generator

A backup generator is a device powered by fossil fuel such as liquid propane, diesel or gas to power your home during an outage. Depending on the size of the generator, it can provide power for your home while fuel supply lasts.

A backup generator is mostly installed outdoors, requiring additional construction work. It may require regular maintenance, as they are used infrequently, to ensure they are functional and have adequate fuel.

Cost Savings of Powerwall vs. Backup Generator

Providing Monthly Value Beyond Backup*

Lower Ten-Year Cost of Ownership

When paired with solar, Powerwall works daily to reduce your monthly electricity bill. Over ten years, these savings can make Powerwall and solar more cost effective than a generator.

Powerwall creates savings by storing excess solar energy to power your home. Powerwall, paired with or without solar, can be set to increase savings with Time-Based Control, using smart charging and discharging to maximize the economic value of your home energy system. 

In some regions, Powerwall can participate in Virtual Power Plants (VPP), a network of homes with solar and battery systems that work together as a single power plant. Stored energy in Powerwall may be used when the grid needs emergency support and through partnering programs, Powerwall can earn you money.

Differences Between Powerwall and Backup Generator

Powerwall Backup Generator
Experience Automatic, < 1 second transition to back up, without interruption 15-30 second delay, before automatic or manual backup
Energy Source Stored electricity from solar panels or the grid Natural gas, liquid propane or diesel
Noise Quiet (< 40 dBA at 1 meter) Louder (77 dBA at 1 meter)
Installation Indoors or outdoors, wall-mounted or floor-mounted Outside, generally on concrete pad, due to odor and exhaust
Maintenance Minimal Refuel, servicing and oil changes
Financial
Value
Reduces your electricity bill by storing solar or energy from the grid when prices are low Has no effect on your electricity bill
Grid
Services
Earn money by participating in Virtual Power Plants and energy retail plans like Tesla Electric Can’t participate in Virtual Power Plants
Warranty 10 years 5 years
Environmental
Impact
Powered by the sun Produces toxic fumes that may expose customers to hazards like carbon monoxide poisoning§

Next Steps

Be prepared for the next power outage and get started by ordering Powerwall for your home. You can also speak to a Tesla Advisor to find out more about Powerwall.

Depending on your area, federal and local incentives are available when purchasing a home battery. Sign up to receive the latest on available incentives, Tesla news, events and product updates.

Additionally, explore resources to understand how Powerwall works:

*Comparison of typical 10 kW backup generator vs. 8 kW solar, 1 Powerwall and backup switch financed with 10-year loan at 7.24% APR and 10% down payment; average U.S. residential electricity costs with 2% annual inflation

Tesla estimates these savings based on typical residential usage for customers on a standard time-of-use residential tariff and that the customer participates in a median number of utility-sponsored demand response events. Actual savings may vary based on your utility provider.

According to the Bureau of Transportation Statistics, a refrigerator humming sound level is approximately 40 dBA while a vacuum cleaner level is about 70 dBA.

§FEMA provides safety tips when using generators at home including being aware of the following hazards: carbon monoxide poisoning, fire and electrocution.