PV system during a power outage—your path to an independent backup power supply

Power outage? It's good when the refrigerator keeps running—with solar backup from SMA.

What happens to your PV system during a power outage? Does it continue to operate? And how can you retrofit your PV system for backup power? This article provides answers – and shows how SMA’s battery storage and backup solutions can help you stay prepared for emergencies.

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Why energy independence matters during power outages

Extreme weather, grid overloads, maintenance work, or even cyberattacks can all lead to power outages. Every household can be affected—and the consequences are often more than just inconvenient: thawing frozen food, lost internet connections, or no lights. While not always critical, these disruptions can be frustrating and costly. That’s why it’s good to know your PV system can continue supplying energy during an outage—thanks to SMA’s reliable backup power supply technology.

What happens to your PV system during a power outage? Understanding how it works

Why doesn’t a PV system work during a power outage? When the utility grid goes down, PV systems are required by regulation to switch off automatically. The anti-islanding protection ensures that no electricity is fed back into the utility grid—protecting technicians and supporting a safe and coordinated grid recovery.

To keep supplying power during an outage, a PV system must disconnect from the grid and form a so-called stand-alone grid. This is only possible with the right components—such as an inverter with automatic or manual backup power function, and in many cases, a battery storage system.

Can a PV system be used as backup power? Your options for greater self-sufficiency

Yes, it’s possible, provided certain technical requirements are met. SMA offers two main backup power solutions:

  • Manual backup power: Manual activation of a permanently installed socket connected to the inverter, e.g., for powering a router, charging cables, or similar everyday devices.

  • Automatic backup power: Automatic switchover to supply the entire household during a grid failure.*

The system becomes especially efficient when combined with a battery storage system. This allows stored solar power to also be used at night or during bad weather. The combination of a PV system, battery, and an inverter with backup function ensures maximum energy reliability.

*High-consumption and high-voltage devices may be subject to limitations depending on the inverter used.

Retrofitting a PV system for backup power—your step toward energy self-sufficiency

Many existing PV systems can be upgraded with moderate effort. The following components are required:

  • Inverter with backup function, for example, the Sunny Tripower Smart Energy hybrid inverter (with integrated automatic battery-backup function) or Sunny Boy Smart Energy (manual backup power function integrated, automatic battery-backup function optionally expandable)

  • Battery storage system (optionally but recommended), such as SMA Home Storage

  • Manual transfer switch or optional backup components such as the SMA Backup 1P or SMA Backup 3P Kit

Retrofitting should always be performed by a certified specialist partner. Costs vary depending on the existing system and the complexity of installation.

Tips for staying self-sufficient during a power outage: get the most out of your PV system

A power outage means loss of control—unless you're prepared. With a PV system featuring backup function and the following tips, you can ensure that essential loads stay powered even during an outage:

  • Protect battery capacity: Set a reserve of at least 20–30% (adjustable via the WebUI).

  • Consider system startup: In automatic backup mode, switchover happens automatically; in manual backup power mode, manual activation is required.

  • Prioritize consumption: Only use essential devices like refrigerators, freezers, routers, and lights. Turn off non-essential appliances.

  • Use energy efficiently: Save power especially at night and when PV generation is low.

Even in exceptional cases, the SMA Energy App keeps you reliably informed about generation, battery status, and consumption—as long as an Internet connection is active.

SMA solutions for emergency and battery backup power

SolutionTypeAutomaticDesigned for home useBenefits
Secure Power Supply (SPS)
integrated into
Backup power, socket can be manually activated❌Single- and three-phase
  • Easy handling
  • Cost-Effective
  • Integrated
Backup 1P*
Available as an option for
Sunny Boy Smart Energy
hybrid inverters		Automatic backup✔️Single phase
  • Automatic switching
  • Supplies entire single-phase households
Backup 3P Kit*
Available as an option for
Sunny Boy Smart Energy
hybrid inverters		Automatic backup✔️Three phase
  • Compact solution
  • Supplies entire three-phase households
Sunny Tripower Smart Energy**Automatic backup✔️Three phase
  • Battery-backup function integrated into the inverter
  • Automatic switching
  • Provides power to the entire household
SMA Home StorageBattery storage system✔️Single- and three-phase
  • Stores solar power for later use

* High-voltage devices (true three-phase loads) such as saunas or circular saws cannot be operated in battery backup mode.

** High-consumption devices such as wallboxes, saunas, or air conditioning units must not be connected to the Sunny Tripower Smart Energy and therefore are not supplied with power in backup mode. This saves energy—allowing the stored solar power to last longer for essential loads.

Summary: Your PV system ensures reliable energy supply during power outages

Safety in exceptional situations

Safety in exceptional situations

In the event of a power outage, your PV system continues to supply energy to the entire household or selected devices thanks to its manual and automatic-backup function—reliably and independently from the utility grid. This ensures you stay well supplied, even in times of crisis.

Stable energy supply with battery storage systems

Stable energy supply with battery storage systems

By combining your PV system with a battery storage system, it becomes a dependable power source, even when the sun isn’t shining. This provides a secure energy supply with greater flexibility in planning.

Independence and future-proofing

Independence and future-proofing

With SMA backup solutions, you gain greater independence from the utility grid. Your PV system becomes the backbone of your energy supply—even during power outages.

Do you have any questions?

Do you have any questions?

Get in touch with our backup solution specialists now.

Contact us