Renewable energies are becoming increasingly relevant and attractive not only for large electricity suppliers, but also for private individuals who want to make their own electricity supply more self-sufficient and thus save costs with photovoltaic systems and electricity storage systems. However, the fire risk of home storage systems is causing uncertainty. Read here about the triggers responsible for storage fires, the challenges involved in solving the problem and how NOVUM is tackling storage fires with its solutions.

The self-sufficient generation of “green electricity” for efficient self-supply while minimizing costs is a promising option for many households in Germany. As a study by the Fraunhofer Institute for Solar Energy Systems ISE shows, the most important current trends in this context include the accelerated expansion of balcony and mini PV systems with an output of up to 2 kilowatt peak (kWp) as well as the growth of battery storage systems through coupled installation with PV systems.

In the field of energy storage technologies, various suppliers have already established themselves on the German market. various providers that offer home storage systems for private households. In line with demand, end consumers therefore have the opportunity to compare a variety of offers and select the provider that suits them best.

The basic advantages of self-sufficient energy supply and storage include savings in energy costs, a payback period of 5 to 7 years and the possibility of feeding surplus electricity into the grid and selling it. In addition to the individual benefits for users, there are also general benefits such as CO2 reduction and therefore environmentally friendly energy generation.
However, since the introduction of PV systems and home storage systems, it has become clear over time that, in addition to the benefits, the new technologies can also pose risks. There have been various incidents of storage fires caused by defective cells. These incidents rightly make interested customers skeptical or encourage them to exercise caution and raise the question: Can home storage systems be purchased and integrated into one’s home without safety concerns?
Causes of storage tank fires:
Photovoltaic storage systems in particular usually consist of galvanic cells, which generally only have low voltages and currents. For this reason, the battery cells are interconnected to form battery modules. Battery storage systems therefore consist of a large number of battery modules that are interconnected in order to achieve higher voltages and currents. In addition, battery storage systems contain components such as ventilation, safety components and switching electronics that are responsible for functionality.
Like any battery-operated device, battery modules harbor a certain risk of fire. The age of the battery, damage or incorrect installation play a role here, which can lead to the battery heating up and thus causing a fire. This is facilitated by the built-in cells, which catch fire at a temperature of 150 degrees Celsius. In the event of a short circuit, the cells can heat up to 700 degrees Celsius and set all the surrounding cells on fire. This is a chain reaction (also known as a thermal runaway ), which is triggered by cell damage and subsequent short circuits. In total, such a chain reaction can heat all cells to over 1,000 degrees Celsius and thus set the entire storage unit on fire. Simply extinguishing a burning storage tank is therefore generally not a solution, as this cannot reduce the heat in the storage tank. The fire department must be called and the cylinder must be removed from the building so that it can be safely extinguished and cooled.
What causes a fire?
Storage tank fires can also be encouraged by various operating procedures:
- Poor production quality of the battery cells or storage units
- Severe mechanical damage to the battery such as cracks or dents
- Mechanical damage to the storage tank, e.g. due to tipping over or falling out of the wall bracket
- High thermal loads due to high ambient temperatures or strong temperature fluctuations
- Wear or exceeded service life of the cells
Necessary measures to protect your own home storage unit:
For the various reasons that promote a home storage tank fire, professional installation, the surroundings of the installation site and regular maintenance are essential safety points that must be observed when installing a home storage tank in your own home.
However, the biggest and most important challenge in preventing fires is the early detection of a defective cell in the storage system. However, this is no easy task. It requires continuous monitoring of the cells (battery diagnosis) to determine the state of charge using the State of Health (SOH) and the State of Charge (SOC) and to be able to recognize and take direct changes into account.
The solution with NOVUM Storage Guard:
It is precisely this challenge of battery diagnostics and monitoring that NOVUM has addressed with the Storage Guard an AI-based solution. This is now used by various home storage providers to identify defective cells at an early stage and thus ensure high safety standards.
NOVUM Storage Guard continuously monitors the storage values and detects anomalies that could indicate defects or overheating at an early stage. It uses AI as a reliable and efficient analysis method. This allows problems to be detected quickly and preventative measures to be taken before a fire occurs. The Storage Guard is already used in the planning phase of each operator to coordinate all necessary processes. It makes it possible to monitor the individual cells around the clock and thus react to the smallest changes and irregularities before problems or even failures occur. The process involved includes high-precision battery status determination (SoC and SoH), which is evaluated using AI. The Storage Guard can be applied to various battery types.
The advantages of the Storage Guard include
- Full transparency and independence
- High-precision battery status determination (SoC and SoH)
- Greater safety and lower maintenance costs
- Reliable fire prevention, fewer breakdowns and predictable maintenance intervals
- NOVUM enables more safety and savings in your fire protection concepts through predictive maintenance.
With this technology, NOVUM supports companies in increasing the safety of their energy storage systems and minimizing risks for the end consumer. This ensures the smooth operation of the systems.
What role does the NOVUM seal of approval play in this?
Suppliers of home storage systems can label their storage systems for end consumers with the NOVUM seal of approval label. It stands for the highest safety standards in the operation of stationary and mobile energy storage systems. The seal stands for the certainty that potential dangers are recognized at an early stage and that the NOVUM experts provide battery manufacturers and users with appropriate recommendations for action. This is ensured by recording comprehensive battery data and transferring it to the NOVUM database, which guarantees continuous, predictive battery monitoring. The seal signals to partners, customers and insurers that the preventive safety technology is state of the art.
