Battery energy storage facilities are a relatively new fixture in power generation & distribution. It is growing though, and we are seeing them more and more. Battery storage systems take the off peak energy and store it for peak time when more energy is needed. In this blog post, we're going to answer the following questions about fire hazards in battery storage rooms to give some insight into this emerging facility space:
• Are batteries the hazard?
• How do we fight battery storage room fires?
• What code do battery storage rooms fall under?
• What are other safety hazards to watch out for in battery storage rooms?
1) Are batteries the hazard?
Short answer: not really. The main issue is how these storage rooms are made. Oftentimes, the rooms weren't built with battery energy storage in mind. They were existing structures and became battery energy storage rooms. The true hazard is the lack of ventilation often found in these rooms. Charging batteries in a fault or overcharge condition can generate hydrogen, which is highly flammable. As little as 4% hydrogen in a poorly ventilated room can cause an explosion and subsequent fires. Hydrogen in the room should be less than 1%, so periodic ventilation surveys need to be conducted to stay safe.
2) How do we fight battery storage room fires?
No one wants to be shocked, correct? So if water is in these spaces, disconnection of the power sources must be considered. There is a high risk of electrical shock and possible toxic water run off with the use of water suppression. Firefighters should use a carbon dioxide extinguishing system. We installed a fire protection system for a battery energy storage room at a natural gas power plant. For this system, we installed a FM-200 fire suppression system, which is a clean agent. It discharges in less than 10 seconds and has little to no clean up. A sprinkler system was also available as a back-up. You can read more about that install here.
3) What code do battery storage rooms fall under?
Battery storage rooms have to adhere to two codes: National Electric Code (NEC 480) and NFPA 70E. NFPA 70E was created to protect personnel by reducing major electrical hazards.
4) What are other safety hazards to watch out for in battery storage rooms?
Battery storage rooms can be difficult to work in. They have limited paths of egress, poor lighting, little working space, rarely a guard for exposed live wiring, and little ventilation. When the battery bank is disconnected, it is still charged. When maintenance, repair, or replacement is needed, the battery system cannot be de-energized. Have your safety director write up a Job Site Assessment (JSA) to find solutions to any potential issues.
While battery energy storage rooms are a relatively new development, they are growing. The energy grid has more solar and wind generation facilities which generate only when the sun shines or the wind blows, not necessarily when power is needed. You will find battery energy storage rooms used to store excess electricity to be used during peak times. We hope this blog post gave you some insight into how to stay safe when working with these structures.