Do solar panels work during a utility outage?

If you don’t have a battery like Powerwall, your solar panels will not work during a utility outage due to grid safety requirements. If you have both solar and Powerwall, you can supply power to your home during an outage by using solar energy directly, as well as using energy stored in Powerwall. Your home’s power supply will operate as an independent system, running on solar energy during the day and storing excess energy for later use. 

What happens when the sun goes down?

Your solar panels will not produce electricity in the absence of sunlight. The system’s inverter will go into “Night Mode” when there’s not enough daylight to produce energy. Once it becomes light outside, the solar panel system will turn back on.

If you have a battery like Powerwall, then you can use its stored electricity to help meet your nighttime energy needs. If you don’t have a battery, then at night, your home will draw power only from the utility grid.

What happens to my solar production on a cloudy day?

Your solar panels can still generate electricity on cloudy days, since even diffuse sunlight can activate solar power production. Solar panel output on a cloudy day may be less than on a cloudless day but will still often provide a meaningful amount of electricity.


What happens if it snows on my solar panels?

While accumulated snowfall can cover panels and temporarily reduce production, this is not a cause for concern. Your system is designed with annual energy production in mind and occasional inclement weather is expected. Don’t worry about shoveling snow off your solar panels. Raking off snow can harm the panels by scratching them or could put you at risk of injury due to falling snow or ice.


If I have a Powerwall, is it better to store solar energy or sell it back to the utility?

The answer depends on personal preference and the amount your utility pays you for solar energy. Selling all excess solar energy to the utility can help offset the cost of a solar installation but at night your home will fully depend on the utility for electricity. Storing energy, on the other hand, decreases your reliance on the utility and can allow you to go for an extended period without using energy from the grid. The Tesla app’s Time-Based Control feature can automatically optimize for your energy storage needs and cost savings goals.

Can I add a Powerwall to my existing solar panel system?

Yes, Powerwall can be integrated with your existing solar system. Powerwall is compatible with solar inverters from SMA, SolarEdge, Fronius, Enphase micro inverter, Delta and ABB. We continue to explore compatibility with other inverter manufacturers.

Visit www.tesla.com/powerwall to get started adding a Powerwall to your existing solar panel system.