There is a misconception that a typical residential solar system will continue producing electricity during grid outages and provide uninterrupted service. After all, if the sun is shining and the grid goes down, shouldn’t the system still work?
In fact, residential solar was historically designed to stop working in the case of a grid outage. This is now changing as solar plus energy storage systems and other future technology improvements add the ability to function during a grid outage. So, how do solar panels work when the grid is down with and without storage?
Grid-Tied Systems without Storage
Residential solar without storage is designed to shut down during a power outage as most customers have grid-tied systems in their homes. First and foremost, this is done for safety reasons. Historically, inverters need grid power to supply a standard frequency to your home. These critical pieces of equipment invert the direct current (DC) power from the sun into the usable alternating current (AC) in your home.
When a customer decides to go solar, the installer will submit an interconnection application to the local utility to receive approval to tie the system to the grid. This ensures that the customer’s home will continue to have electricity during the night or when there are clouds overhead. Additionally, grid-tied systems allow the solar array to send any excess energy produced back to the grid. This excess production will be exchanged for a net metering credit on the utility bill or a feed-in-tariff credit. In effect, the grid is functioning as a storage device, but only a monetary one. If a grid outage occurs, the system will stop working.
It is also important to note that grid-tied systems often shut down to protect utility workers who may be working on fixing the lines during an outage. Again, safety is always paramount.
Grid-Interactive Systems with Storage
If you want to guarantee that your solar system will continue to operate during a blackout, adding a battery storage system is the way to go. These storage units save energy produced from solar panels for later use. When there is a power outage, the combined solar plus storage unit isolates itself from the grid and immediately continues power supply to the home—providing the uninterrupted electricity service you need during times of crisis.
Just as sizing the solar energy system is important, choosing the right storage unit requires careful evaluation. Depending on your home’s energy profile, you can size your energy storage system to supply your most essential energy devices or it can be sized larger to accommodate even more appliances during a grid outage. Local incentives, electricity costs, and peak demand charges can also be critical factors to consider based on your goals. We recommend meeting with a local member of the Enphase Installer Network to learn the particulars about your situation.
All-in-one solar plus storage
Solar plus storage with Enphase is unique because it is an all-in-one approach to inverter technology, storage, and software. This allows it to seamlessly create a grid within your home to keep you operational during a blackout. The system can even prepare itself for a storm by charging the storage unit in advance through its innovative Storm Guard™ feature.
For first-time solar storage system buyers, the most important question that is probably on your mind is the following: can I power my essential appliances during a grid outage? The answer is an unequivocal yes!
For example, the IQ Battery storage system provides enough power (up to 1,280 watts) to run a refrigerator, 10 LED bulbs, a router, three cell phone chargers, a laptop, a 55” TV, and an electric fan at the same time. If you want even more to backup, adding more IQ Battery could even power additional gaming consoles, monitors, and air conditioning units.
If you are enjoying the benefits of your residential solar system but want to take it a step further to adopt off-grid features and have uninterrupted electricity during a power outage, solar plus energy storage is the way forward.
Get started by learning more about Enphase and the all-in-one smart home energy system.