The exact industry-wide risk for wind turbine fires is hard to pin down. Statistics vary between sources from 1 in 2,000 to 1 in 15,000. As the number of operating wind turbines grows, the total number of wind turbine fires per year will increase unless owners and operators fully manage fire risk.
Our reports interviewing key figures in the wind industry confirm that the industry takes fire risk very seriously. But often, owners and operators don’t always know where to start when it comes to evaluating their wind turbine’s fire risk and how best to safeguard their assets.
To help with the process, we have outlined four main steps involved in fire mitigation research, walking you through the process to help you reach the conclusion that will best protect your assets:
1. Understanding how and why turbine fires start
This step is all about the why. Turbines have all the components needed to cause sparks that build into a fire, such as the interaction of oxygen, heat, and materials that can fuel fires, like fiberglass or carbon structures. All that is needed is an ignition source.
However, wind turbines do not spontaneously combust for no reason. Most turbine fires occur due to a mechanical or technical error in the turbine, which is the primary ignition point. The parts most likely to catch fire are transformers, converters/capacitors, the nacelle brake area, and the hydraulic area.
Due to the conditions highlighted above, a fire in a turbine can spread quickly. Once a fire breaks, the entire turbine can be damaged beyond repair because of the limited resources available to fight a rapidly spreading fire.
2. Performing internal risk evaluations
This step is all about the infrastructure – once you know why and how a fire can start, it’s important to narrow down risk evaluation to your specific wind asset.
In conducting an internal review of your wind assets, owners and operators must weigh up the turbine’s vulnerability to fire risk. Due to the commendable progress in the industry, most turbines already have passive fire suppression measures in place. These measures include using less-flammable materials to build the turbines, minimizing the probability of a spark building into a fire. Many turbines are also designed with electrical braking systems to prevent sparks in the event of a sudden stop. However, despite this – many fire risks simply cannot be designed out, and in the unfortunate case of a fire starting, asset owners must evaluate the likelihood of significant damage.
If a fire were to occur, how would the asset hold up, and what type of damage would be done? The answer depends on a number of factors, such as the flammability and combustibility of different materials making up the turbine, where components are located, and whether active fire suppression methods are in place.
If the turbine doesn’t have in-built suppression systems, the damage will most likely result in a total loss of the nacelle. Because of the location of onshore wind farms, mostly in rural areas with rugged terrain, it could take a ground-based fire truck a substantial amount of time to reach the turbine on fire. Once they arrive on the scene, the ground-based fire crew won’t have the resources to access the nacelle to fight the fire, which could stand at heights over 300+ feet. It is even more difficult for offshore wind owners and operators to secure a firefighting vessel to reach the turbine on fire, and offshore wind platforms are generally larger than their onshore counterparts.
A final consideration in this step is calculating loss scenarios for your turbine in the event of a hypothetical fire and what the cost implications would be. In an unprotected wind turbine, fire can quickly spread through the nacelle, resulting in extensive damage. Severe fire damage often necessitates replacing the whole nacelle or turbine, costing the project $7-8m on average.
Furthermore, if a fire starts in an onshore turbine and then spreads to the locale, resulting in a wildfire, the project could be exposed to billions of dollars in liability.
The cost will also need to factor in how insurance coverage would come into play. Due to the rising number of turbine fires, insurance rates have increased 20 to 30%.
3. Engage expert opinions to research your options
This step is all about exploring fire prevention methods, detection, and suppression, based on best practices throughout the industry.
Many technologies and practices are focused on prevention. As discussed earlier, this includes design-level decisions, such as the use of less flammable materials, but can also have operational procedures, like comprehensive maintenance planning to prevent electrical and mechanical breakdowns. However, while fire prevention reduces the likelihood of a fire, these measures will not prevent damage in the rare case that a fire does break out. In this case, you will want to understand what options you have to stop a fire before it can grow.
Fire detection alerts owners and operators to fires. This technology detects fire through several methods, often by identifying smoke or sudden heat. As a result, owners and operators are alerted to the fire but have limited to no capabilities to prevent the fire from spreading.
However, only fire suppression systems can suppress a fire and prevent damage once a fire has started. Firetrace’s automatic fire suppression systems are made up of detection tubing filled with a clean agent. On contact with extreme heat, the detection tubing ruptures and releases the agent to put out the fire at its source. Thus, only fire suppression systems using a clean agent have these three components: effective at fighting fires, safe for people, and environmentally friendly.
It is advisable to ensure all three fire protection methods – prevention, detection, and suppression – are present in a wind turbine.
4. Make a decision
Once you’ve quantified your turbine’s exposure to fire risk and level of current fire protection, you can now decide what you need to invest in to ensure turbine fire risk is fully managed.
As the industry grows and more turbines go online, the expected number of turbine fires per year is likely to increase. The cost of fire safety methods pales in comparison to the cost of restoring a wind turbine following a fire. Prevention and detection are important, but suppression puts a stop to the disaster.
Firetrace’s system specifically targets ignition sources in the wind turbine, which allows a flexible, modular approach to fire protection that is customizable for different turbine makes and models.
Firetrace is the expert in fire suppression for wind turbines. We are here to assist you in learning more about the cost-benefit of installing automatic fire detection and suppression to protect your turbine from fire risk.
