As energy storage system (ESS) deployments expand globally, Jim Dickinson of Fireaway explains how NFPA 855, early warning systems and layered ESS fire protection strategies are helping operators identify thermal runaway risks
What fire risks do energy storage systems present that fire service professionals need to be aware of?
One of the challenges is that there are many misconceptions around energy storage systems (ESS) and where those fires start. Everyone talks about lithium battery fires and the role they play, but around 90% of fires do not actually start in the battery itself. They start in the electrical areas of the ESS.
The batteries are getting a lot safer. The newer generation of batteries is improving, but if a battery goes into thermal runaway, you get a mixture of gases coming off it, and they are very difficult to deal with.
Once it gets into a deep-seated lithium fire, there is not really any product on the market that can simply put that out. At that stage, you are struggling to contain it. For us, the focus is twofold.
The first part is providing a layered fire protection approach across ESS. The first stage is prevention. We do that using UltraSense. We have an all-gas flammable sensor that provides early warning. It is UL-listed, and it gives warning before an event develops.
We can link that to the battery management system in the ESS. We do that with a number of partners globally, and that is the first key part of the approach.
The next part is detection. We use standard detection, and we work with partners to provide those detection systems Suppression is provided using Stat-X aerosol. That is designed with our engineering team to protect the areas at risk.
We are trying to get to the earliest possible stage of fire protection. The aim is to get an early indication and connect that with the battery management system, so people can get to site before the situation develops.
How do fire protection strategies vary between utility-scale ESS sites and smaller in-building installations?
Large-scale ESS sites have a lot more management around them. They are more detailed, with more energy management and more fire detection and suppression planning.
They also need more planning at local level. If you go somewhere like California, you have local authorities having jurisdiction (AHJs) making decisions around what can go in and how it can be deployed.
In Europe, it is very different. Europe does not have its own standard for this, so everybody follows National Fire Protection Association (NFPA) 855. That is the global industry standard.
It would be good if other standards were being presented, but NFPA 855 is the main one that is out there. It is the one we follow, and it is the one the ESS manufacturers use.
I was in China last week, and that is the standard everybody is following there as well. Some companies say that, if they are in Europe, they need to use a European Norm (EN) version. The issue is that there is no EN approval for an ESS system.
There is no European or UK standard for that. The biggest point is making sure the risk is assessed at the early planning stage. Firefighters and fire professionals should be engaged early, as they are in the United States (US), where the local AHJ will be involved. Europe is a little different.
Australia is slightly different as well, with its own regional variations. It is a tough area, because practices vary by region. Batteries are also changing. We used to have large 40-foot containers with plenty of space to install systems.
Batteries have now become more condensed. They have improved efficiency, and systems have become smaller, more compact and lower risk.
That was one of the reasons we got into UltraSense. It allows us to offer something compact that can go into those areas and detect early. That was important for us. In the US, fire marshals are heavily involved in decisions.
In Europe and the UK, that level of involvement is generally not there in the same way. With smaller-scale systems, we see this in charging facilities and in buildings. There is a risk, but those systems are often not assessed in the same way.
We have seen buildings where people have not carried outa full risk assessment and have not properly assessed the hazard itself. That is where the issue sits.
Could you explain how condensed aerosol systems are applied within ESS environments and what they are designed to achieve?
The suppression part of the approach is Stat-X aerosol. It is designed to protect the areas at risk within the ESS. It forms part of a wider layered approach. UltraSense gives the early warning, standard detection can sit alongside that, and Stat-X provides suppression for the protected areas.
The key point is that this is designed around the risk. Our engineering team works on that design to make sure the system is protecting the right areas.
What role does early detection play in identifying thermal runaway and supporting effective incident response?
Early detection is the key to this. UltraSense can be linked to the battery management system. That allows the system to identify the cell that is starting to go off and allows everything to be shut down.
You then have standard detection alongside that, followed by suppression. That is the approach we take. The aim is to get a warning as early as possible, before the situation develops into something more difficult to manage.
How are standards influencing how ESS fire protection systems are designed and deployed?
NFPA 855 is the main standard being followed globally. Even in China, that is the standard everybody is following. ESS manufacturers are using it, and it is the one we follow.
There is no EN approval for an ESS system at the moment, so if somebody is looking for a European or UK standard, there is not one in place in that form. That means NFPA 855 has become the main reference point across the industry.
When operators or fire services assess ESS protection solutions, what factors guide decisions?
The main factor is whether the risk has been assessed properly. That needs to happen at the early stage, during planning. Firefighters and fire professionals should be involved from the start.
In the US, the local AHJ is involved in those decisions. In other regions, that involvement can be different, so the process needs to reflect local requirements. The other factor is whether the system provides a layered approach. For us, early warning should be supported by detection, with suppression designed around the areas at risk.
What lessons from recent ESS incidents should fire service professionals consider when planning for future risks?
The main lesson is that the hazard needs to be assessed properly. People often focus only on the battery, but most ESS fires start in the electrical areas. That needs to be understood when systems are planned and protected.
The other lesson is that early warning matters. If you can identify a problem early, link that information to the battery management system and shut things down, you have a better chance of managing the risk before it develops.
That applies across utility-scale systems, charging facilities and smaller systems in buildings. The scale changes, but the need for proper assessment and early engagement remains the same.