Reducing wildfire risks caused by electrical networks: How the Spark Prevention Unit strengthens grid resilience

Wildfires are rapidly increasing in frequency and intensity across the world¹, now threatening not only forests, but also urban areas, agriculture, and critical infrastructure.

Its impact on families, livelihoods, and regional economies is growing as many fires start from everyday incidents, such as unattended campfires, discarded cigarettes, or burning debris. Electrical faults are often overlooked, but they also play a role, with failures that may escalate quickly.

Addressing this challenge requires robust prevention and response strategies, innovative solutions, and global collaboration to sustainably and proactively protect communities, environment, and infrastructure.

Electrical equipment installed in fire-prone areas can be potential triggers for wildfire. In dry environments, even minor malfunctions can create sparks that could ignite nearby flammable materials, potentially leading to wildfires that threaten communities and ecosystems. This connection between hidden and real-world consequences highlights the importance of proactive maintenance and innovation to build safer, more resilient energy systems.

Surge arresters are critical yet unseen safeguards across the power grid. Designed to shield equipment from the effects of lightning strikes and unexpected momentary voltage surges, they protect against damage that can compromise reliability.

Surge arresters are found along distribution lines where they protect transformers, cables, and other components. At power generation plants, they support the reliable operation of sensitive generation equipment. In substations, they reduce the risk of insulation failures, which could trigger large-scale outages. Industrial facilities also depend on surge arresters to protect critical machinery and keep operations running smoothly. As their importance grows, so does the potential to further strengthen their safe and reliable operation. However, when a surge arrester overheats, it could fail and then release sparks or hot particles, posing a risk to surrounding equipment and the environment.

The Spark Prevention Unit (SPU) can be compared to an airbag in a car: both are designed to react instantly to danger and stop a situation from becoming catastrophic.

Just as an airbag detects a collision and deploys within milliseconds to protect passengers before serious injury occurs, the SPU detects – faster than an airbag – when a surge arrester is about to fail and disconnects it, thus preventing a spark or hot particle and immediately neutralizes the threat before it can ignite a fire. The system doesn’t simply warn of danger; it acts automatically, at high speed, to prevent escalation and protect people and assets.

The SPU is a pioneering solution designed to quietly disconnect an overloaded surge arrester before failing. Acting as a thermal sensor, it continuously monitors the leakage current and acts early enough to disconnect the surge arrester when levels rise beyond acceptable thresholds that indicate a prospective failure. This ensures that the disconnection is safe and spark-free, thus supporting wildfire prevention and limiting the risks and improving the safety of people, nature, and wildlife.

With its compact design, the SPU integrates easily into existing infrastructure without disrupting operations. Small in size but with a significant impact when we talk about wildfire prevention.

In high wildfire-risk areas, the SPU helps prevent the cause of sparks, making surge arresters safer in dry, flammable vegetation areas. Installed on surge arresters located at critical points across the grid, it adds an extra layer of protection for surrounding communities and ecosystems.

As energy systems expand and operate under more demanding environmental conditions, the SPU strengthens grid resilience by ensuring a spark-free solution under fault conditions.

Hitachi Energy drives sustainable grid modernization. By partnering with communities, utilities, and industries worldwide, it helps strengthen infrastructure in a rapidly changing and increasingly demanding energy landscape.

Building on decades of innovation and a proven track record in fire prevention in dry areas, its approach to spark mitigation addresses a critical yet often overlooked risk – helping prevent wildfire ignition even in harsh environments with dry surrounding vegetation.

The SPU is more than a technical solution. It helps utilities move beyond compliance and implement real actions that support and safeguard people and ecosystems. By enabling a spark-free disconnection of overloaded surge arresters, the SPU reduces ignition risk right at the source. In doing so, it empowers communities on a path to a more secure and sustainable grid.