But why not?
They require additional components, including a transfer switch and batteries (or a SunLight Backup by Enphase), are added as part of the design. This is a code requirement and also a design/manufacturing limitation of solar power electronics.
- Safety: To create backup during an outage, the output of the solar system needs to be able to disconnect from the grid for safety reasons, so-called “Anti-Islanding” protection, to prevent sending power into the failed grid and electrocuting linemen.
- Inverter Design: inverters that convert DC (at solar panels) into AC (usable electricity) are designed to synchronize with the existing grid frequency/sinewave, which is disrupted during a power outage.
Backup Options in the Solar Marketplace:
Battery Backup (Energy Storage/ESS)
Adding energy storage is a common practice for existing solar owners. AC-coupled ESS is solar panel/inverter agnostic, making a power backup achievable for anyone. ESS can be purchased at the same time as the solar project or added later. Most installers will offer a discount to install it at the same time due to reduced overhead and mobilization costs. Tesla Powerwall is one example of a well-integrated AC-coupled storage solution.
Enphase has a unique solution that allows for energy backup to use during the outage directly from the sun. I costs less than the battery backup, but also has a lot of limitations due to the nature of the inconsistencies of direct sunshine availability. For example, it doesn’t help to stay cool at night, and the power output available may vary. This setup still requires extensive house rewiring, including the transfer switch, gateway, system shutdown switch, and load controller. Sunlight backup also requires IQ8 generation Enphase microinverters. The good news is, it is battery-ready for future Encharge battery add-ons.
Bi-directional Vehicle Charging
With EV adoption quickly accelerating, a lot of manufacturers are looking to the existing automotive batteries to provide battery backup for the home. Currently, Hyundai and Ford already have those available, and many more are expected to become available soon. Keep in mind that this option also requires a significant cost of gateway installation and any required wiring to make it work properly.
But salesman with the other solar company told me that I can produce power during an outage!
Unless you have one of the above solutions, solar panels have no way of powering your home during an outage
Where does the electricity go, if the system is turned off during an outage?
Energy is not drown from the solar panels during the power outage. This is similar to a car battery that is not being used, and is waiting for that starter to draw power for as long as necessary. Solar system is in a safe standby mode, periodically checking for the grid to reurn and be stable for a period of time before turning on again to offset your energy use.
Can Conventional Solar System Produce Power During a Power Outage?
Only if a backup option is provided and priced in as part of the design and installation. Just like the solar panels themselves, it has to be properly designed to work with the energy demands, existing electrical infrastructure, and the solar energy aspects of the project.
Can I add Energy Storage to an existing solar system?
Yes, an ESS retrofit is a common solution to energy storage needs.
Can I add Encharge Battereis to a Non-Enphase solar system?
No, Enphase backup only works with Enphase microinverters.
Ho much does Energy Storage System costs?
A typical whole-house backup will cost approximately $30,000 after all expenses are added.
Can I finance my Energy Storage?
Yes, financing is available (credit approval required), and PPM Solar is happy to point you in the right direction to apply.
Is Retrofit Solar Energy Storage Tax Credit Eligible?
Yes, batteries that are added to a solar system that are charged by the solar system are eligible for the Federal Solar Tax Credit. Please consult your accountant for eligibility and details.
What are some other benefits of adding Energy Storage System?
Some of the advantages of adding your own Energy Storage System include the improved Self Consumption (reduced Net Metering) and the resulting benefits in those areas where full net metering is not available, such as Clay Electric, or Jacksonville Electric Authority (JEA). If you have a utility that doens’t net meter, batteries play that role by storing the excess energy produced during the day and reducing/preventing the need to go to the utility at night.
Additionally, during an outage, there may be additional benefits to the Solar Energy Storage if the generator fuel is not available. Imagine if gas stations shut down for weeks, and your home still has power, air conditioning, and your EV has plenty of juice to go around town! That can make a dramatic difference that is hard to put a pricetag on in an emergncy.