Surge Protection in 2025: Keeping Your Assets Safe

Summer 2025 has already shown that nature and technology are not always compatible. Across Europe and Asia, severe thunderstorms have highlighted a persistent question: is your infrastructure protected? In today's hyperconnected grid, with distributed generation and digitalization, surge protection is essential.

Surges are not new, but the risks have increased. Sensitive electronics now control everything from residential heat pumps to hospital MRI suites. Even smart meters have become critical data nodes. A single unmitigated surge can cause extensive damage, disrupt services, and trigger failures across the network. As we look at 2026, it's important to review what's changed, the ongoing risks, and how best to protect assets.

What's Changed Since 2020

Electrical systems have become more complex and vulnerable. Distributed generation—solar, wind, and storage—is now common. Electric vehicles and IoT devices are everywhere, increasing the number of entry points for surges.

This progress brings new risks. More sensitive equipment means even minor voltage spikes can cause major problems. The grid is smarter, but also more exposed.

Types of Surges

Not all surges are the same. According to IEC 61643-11:2023 and IEC 62305-1:2010, lightning-induced surges result from direct or nearby strikes. These surges travel along conductors, often targeting switchgear or control cabinets.

Internal surges are usually caused by switching events—circuit breakers, motor starts, or capacitor banks. These are frequent and can degrade equipment over time.

Grid disturbances, including operational errors, remain a leading cause of surges. While cyberattacks do not directly cause voltage transients, they can trigger actions that result in surge conditions. Digital and physical risks are increasingly interconnected.

Protection Methods

Surge protection requires a layered approach.

Surge Protective Devices (SPDs):
SPDs divert excess voltage to earth, protecting downstream equipment. In 2026, SPDs include real-time monitoring and predictive failure alerts. According to IEC 61643-11:2023:

Type 1: For direct lightning, installed at the main distribution board.
Type 2: For switching and indirect surges, at sub-distribution boards.
Type 3: For sensitive equipment, installed close to the device.

Select SPDs with a voltage protection level (Up) below the withstand voltage of your equipment, as defined by IEC 60664-1.

Coordination with Circuit Breakers and Fuses:
SPDs must work with overcurrent protection devices. Proper coordination ensures the SPD absorbs surges, while breakers and fuses isolate faults.

Installation and Maintenance:
SPDs require short, direct earth connections, regular inspection, and timely replacement. Many now offer remote diagnostics for easier maintenance.

Case Studies

A utility in southern Germany upgraded its surge protection—Type 1 SPDs at substations, Type 2 at distribution cabinets, and Type 3 at endpoints, all with Up values below equipment ratings. During severe storms, they reported zero equipment failures, while neighbouring utilities faced outages and costly repairs.

In contrast, an industrial plant in Southeast Asia skipped surge protection on several panels. A switching surge caused a 36-hour outage and significant losses—far more than the cost of proper SPDs.

Future Trends

Smart SPDs:
Modern SPDs include sensors and connectivity for real-time monitoring and predictive alerts. Integration with AMI allows utilities to track protection status across networks.

Predictive Maintenance:
Data from smart SPDs and IoT sensors enables proactive maintenance, reducing downtime.

Regulatory Updates:
Standards such as IEC 61643-11:2023 and IEC 60664-1 now provide updated guidelines for SPD selection, installation, and testing. In some regions, surge protection is mandatory for certain equipment.

Takeaway

Surge protection in 2026 requires adherence to updated standards, careful SPD selection, and regular maintenance. Fault-induced switching surges remain a key risk, and cyber-physical events can act as indirect triggers. Proper insulation coordination and ongoing inspection are essential.

The cost of inadequate protection is high: equipment damage, data loss, downtime, and reputational harm. With the right measures, most surges become routine events with no impact.

At CLOU, surge protection is part of our technical consultancy. We specify the right SPDs, apply the latest standards, and support you with best practices to keep your assets protected and your operations reliable.