Store solar power

Batteries for PV systems

House at night with lights on

Your energy when you need it

A battery storage system can significantly increase the self-consumption rate of the solar power you generate. At the same time, your energy costs are reduced because you are less reliant on electricity from the public grid. Your surplus solar power is stored in the battery for use during peak demand or nighttime hours.

The ideal choice for your perfectly tailored complete PV solution.To provide you with the best possible support in maximizing your self-consumption, we have developed our own storage solutions: the Fronius Reserva and Reserva Pro. They have been designed as the perfect partners to our hybrid inverters Fronius GEN24 Plus and Verto Plus and are available in various capacities. The lithium iron phosphate technology guarantees maximum safety and a long service life.

The ideal choice for your perfectly coordinated system PV solution.

GEN24 inverter with Reserva storage and Wattpilot Flex e-car charging solution
More security, more benefits
Optimize self-consumption
Use more of your own solar power and reduce energy costs.
Increase independence
Benefit from solar energy around the clock and increase grid independence.
Secure supply in the event of a blackout
In Full Backup mode, the battery is essential for supplying the household with energy even during a blackout.
Optimize self-consumption
Use more of your own solar power and reduce energy costs.
Increase independence
Benefit from solar energy around the clock and increase grid independence.
Secure supply in the event of a blackout
In Full Backup mode, the battery is essential for supplying the household with energy even during a blackout.

Fronius storage solutions

Fronius Reserva Pro
Our scalable battery storage system delivers impressive charging and discharging performance for agricultural, commercial, and large residential applications.
Available capacities: 12.0 kWh – 32.0 kWh
Up to 128 kWh via parallel connection
Fronius Reserva
Our modular high-voltage battery integrates seamlessly into existing PV systems and, with its flexible storage capacities, offers the right performance for every private household.
Available capacities: 6.3 kWh – 15.8 kWh
Up to 63 kWh via parallel connection
Compatible partner batteries
Fronius inverters are also compatible with some PV storage systems from BYD and LG.

All you need to know about Fronius battery storage systems

FAQs about Fronius batteries

With a Fronius battery, you can store surplus solar power and use it exactly when you need it. This makes you less dependent on rising energy prices and increases your self-sufficiency.

The Fronius Reserva and the Fronius Reserva Pro are high-performance battery storage systems for storing and utilising self-generated solar power and can be seamlessly integrated into the Fronius energy system. Both storage systems enable a high degree of energy independence, are flexibly expandable and can also be used for backup power applications.

The Fronius Reserva was developed specifically for residential properties and stands out thanks to its sleek design and flexible storage capacities. The Fronius Reserva Pro is suitable for applications with higher energy requirements and greater power demands, making it the ideal solution for larger residential properties, agricultural businesses and small and medium-sized enterprises. Thanks to the practical click system, the Reserva Pro is particularly easy and efficient to install. Furthermore, its cells and modules are manufactured in Europe, which ensures high quality standards, short supply chains and a reliable value chain.

It is possible to retrofit individual battery modules into an existing battery tower or to add additional battery towers. This allows the storage capacity to be flexibly adapted to rising energy requirements, for example following the purchase of an electric vehicle, a heat pump or other electrical appliances.

To make optimum use of the storage capacity, Fronius recommends carrying out the expansion within the first two years of commissioning. An expansion is still possible even after two years. In this case, however, the newly added battery module will be adjusted to the State of Health (SoH) of the existing battery system.

Yes. The model designations for Fronius batteries refer to the storage system’s actual usable capacity. For example, with the Fronius Reserva 12.6, the specified 12.63 kWh is available for operation.

Deep discharge is prevented. The battery storage systems have an integrated safety buffer, which is not included in the usable capacity and protects the battery from deep discharge and premature cell ageing. This means that, from the user’s perspective, the state of charge (SoC) can drop to 0 % without compromising the battery’s service life or safety.

The optimal battery size depends on your electricity consumption and usage profile. As a general guideline:

  • Average daytime electricity consumption: Battery capacity (kWh) = Annual electricity consumption (kWh) ÷ 1,000 × 1.2
  • Low daytime electricity consumption: Battery capacity (kWh) = Annual electricity consumption (kWh) ÷ 1,000 × 1.5

For the optimal sizing of your battery system, please contact your installer.

When used in combination with a backup power switch-over component such as the Fronius Backup Switch or Backup Controller, the Fronius hybrid inverter can continue to supply power to selected loads or even the entire building using PV production and energy from Fronius batteries during a power outage. Even during a power outage, surplus PV energy can be stored in the battery for later use, maximising energy availability and self-sufficiency.

Safety is the core of every Fronius battery. They utilise the particularly safe and thermally stable lithium iron phosphate (LFP) technology, which is market-leading for its high level of safety, reliability and longevity.

An intelligent battery management system (BMS) continuously monitors key operating parameters such as voltage, current and temperature, and detects potential deviations at an early stage. This is complemented by a multi-level safety concept at cell, module and system level, featuring integrated protection mechanisms and automatic safety functions. This prevents critical operating conditions and ensures reliable operation over many years.

Downloads

    The Fronius Reserva and Fronius Reserva Pro are covered by a 10-year manufacturer’s warranty. The guaranteed State of Health (SoH) at the end of the warranty period may vary depending on the country and region and ranges from 70 % to 80 % of the original storage capacity.

    You can find the detailed warranty terms and conditions, as well as the SoH values applicable to your country, in the relevant warranty documents.

    Downloads

      Fronius batteries are designed for a long service life. Thanks to state-of-the-art lithium iron phosphate (LFP) technology and intelligent control systems, they reliably store and supply solar energy for many years. The actual service life depends, among other things, on usage, operating conditions and charge cycles, and may significantly exceed the warranty period.
      The LED display on your Fronius battery provides key information about the battery's operating status at a glance. It indicates the current operating status as well as any active warnings or error messages. In addition, the Fronius Reserva display shows the battery's state of charge (SoC) and whether the battery is currently charging or discharging.

      Yes. With Fronius Solar.web, you can keep track of your energy flows at all times via the app or web browser. For example, you can see how much solar energy is being generated, stored, consumed or fed into the public grid. In addition, the battery’s current charge and operating status are also displayed in Solar.web.

      In conjunction with the Energy Cost Assistant, you can further optimize battery usage by preferentially storing surplus solar energy and using it during periods of higher electricity prices. This helps increase self-consumption and reduce electricity drawn from the grid.

      Learn more about the Fronius Energy Cost Assistant:

      Detailed charging and discharging power ratings for Fronius batteries in combination with different Fronius inverters can be found in the respective solution sheet.

      All system data relating to Fronius batteries is stored and processed exclusively in Europe. This means you benefit from a high level of transparency, strict European data protection standards and full control over your energy data.
      Your Fronius battery must be installed by a qualified electrician or an appropriately certified specialist company, such as a Fronius System Partner. This ensures that the system is professionally planned, installed and commissioned. You must not connect a battery storage system to your home or the mains electricity supply yourself. Installation and commissioning must always be carried out by qualified professionals in accordance with the applicable regulations. You can find a suitable Fronius System Partner here.

      Fronius batteries are not simply disposed of at the end of their service life. Our aim is to keep batteries and valuable raw materials in circulation for as long as possible.

      When a battery is taken out of service, specialist partners first check whether it can still be used. If this is not feasible, the battery modules are recycled professionally and valuable materials are returned to the raw materials cycle.

      To this end, Fronius works with qualified take-back and recycling partners and supports the sustainable recovery of the materials used.

      If your battery is to be taken out of service, please contact the installer or dealer from whom you purchased the system. They are obliged to take back the battery free of charge and to arrange for its proper disposal.

      FAQs about the Digital Battery Passport

      The digital battery passport is a requirement under the EU Battery Regulation and is mandatory for stationary battery storage systems with a capacity of more than 2 kWh from 18 February 2027. It provides important information about a battery throughout its entire life cycle in digital form. This includes, for example, product data like the State of Health (SoH) and State of Charge (SoC), technical specifications and other information required by law. Fronius will provide all affected battery storage systems with a digital battery passport in accordance with the legal requirements.
      The digital battery passport can be accessed via a QR code on the battery storage system’s Battery Management System (BMS). By scanning the QR code with a smartphone or tablet, the stored information can be viewed digitally at any time. A separate battery passport is provided for each Fronius battery tower.
      No. Fronius is responsible for creating and providing the digital battery passport. There is no additional effort required from you. The information can be easily accessed via the QR code whenever required.
      No. Battery storage systems that were placed on the market before the battery passport requirement came into force do not require a digital battery passport to be added retrospectively.

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