In a significant leap towards enhancing power grid safety and reliability, the Externally Gapped Line Arresters (EGLA) technology has emerged as a game-changer. Originating in Japan 40 years ago, EGLA employs Metal Oxide Varistors (MOVs) to prevent lightning-induced outages on overhead lines, with the first units installed over 30 years ago. Despite its global development, the full potential of EGLA remains underappreciated, prompting French TSO, Réseau de Transport d'Électricité (RTE), to shed light on its applications and benefits.

RTE, a pioneer in high-voltage applications, is sharing valuable insights into how EGLAs address critical challenges in power grids, aiming to demystify EGLA technology, offering a comprehensive understanding of its technical intricacies, safety protocols, and operational efficiencies for the protection of critical equipment, such as power transformers. With a focus on educating industry experts and policymakers, RTE showcases EGLA's untapped potential for elevating grid reliability and safety, marking it as a significant advancement in high-voltage applications globally.

The journey with EGLAs began for RTE in the late 1990s when the technology was incorporated to address concerns related to fault currents following lightning flashovers. The unique approach of interrupting follow currents post-drainage of lightning impulses proved effective in preventing ground potential rise, thus ensuring safety for both electrical equipment and individuals in proximity to transmission line towers.

Distinguishing EGLAs from Non-Gapped Line Arresters (NGLAs), RTE explains the fundamental differences and why EGLA was chosen for its applications. The centralized approach in France played a pivotal role in standardizing EGLA use, ensuring insulation coordination among multiple air gaps. Tailoring EGLA sets to various voltage levels, RTE emphasizes their "plug-and-play" nature, allowing for efficient deployment without service interruptions.

Addressing safety concerns associated with EGLAs in France, RTE highlights stringent regulations ensuring electrical infrastructure does not compromise public safety. While EGLAs are globally predominant for reducing lightning-related network outages, in France, their primary use is mitigating ground potential rise risks. This aligns with France's commitment to robust safety criteria, covering various elements in power lines, towers, cables, and substations.

Despite the lack of specific failure rate data, RTE attests to the reliability of EGLAs within its operations, with a focus on live-line work for voltage networks ranging from 63kV to 400kV. The careful integration of EGLAs into power systems, coupled with adherence to safety standards, promises a bright future for this groundbreaking technology.

Learn more about the future of EGLA implementations, technological advancements, and strategic considerations in the full article.