Existing Solar Battery Backup vs Standby Generator

For a house that already has rooftop solar, which retrofit makes more sense for outage protection: adding battery storage or installing a standby generator?

One development worth checking is Enphase’s recent claim that its IQ Battery 10C and whole-home backup can be added to some existing third-party solar systems in the United States and Canada without replacing the rooftop equipment. Since that’s a company announcement, I’d want the installer to verify actual inverter compatibility, transfer equipment, permitting, and whether the existing system can keep charging the battery during an outage.

The comparison seems less obvious than it used to be:

- **Battery backup:** quieter, no fuel deliveries, and potentially able to use solar for longer outages. The questions are usable capacity, peak loads, winter recharge, battery location, and whether whole-home backup requires multiple units or a service-panel upgrade.
- **Standby generator:** familiar whole-house coverage and longer runtime as long as fuel is available, but it adds combustion-engine maintenance, testing, noise, and dependence on natural gas or stored propane. It also may not operate indefinitely if the fuel supply is interrupted.

For resale, would buyers value an integrated solar-and-battery system more than a generator, or is a generator still easier for them to understand and maintain? I’m also curious how installers are handling older solar arrays: are they recommending a battery retrofit, a generator with a backup controller, or keeping only selected circuits on backup?

Sources for the current development:
Enphase Energy Brings IQ Battery 10C and Whole-Home Backup to Existing Third-Party Solar Systems
Governor Meyer Announces Delaware Shines, The State’s First and Country’s Most Comprehensive Solar Storage Program - State of Delaware News