It’s springtime in the northern hemisphere, which means more lightning strikes to wind turbines. Most of the time they can handle the strikes, no problem. But in rare instances lightning does tremendous damage. When asked about a damaged turbine, lightning experts usually respond that ‘it’s force majeure’, or ‘it was a super-bolt™’. Not elegant responses, but the wind owners, operators, and insurers hear it a lot. How did we get here, and what really matters in turbine lightning protection? These are the important questions this spring.
Lightning is often described as a complex, undefinable, uncontrollable force of nature to a combination of Thor, The Flash, and Storm. Everybody loves superheroes, but lightning is not that complex. Lightning is made of air. It’s super-heated air, but it behaves in predictable patterns and is subject to the same laws of physics as the rest of the world. For example, wind gusts can push lightning tens of meters downwind, which is important to consider when designing wind turbines. …. read the full article in PES Magazine here.
Lightning behaviour: what we’re missing in blade protection
Lightning damage varies with polarity, different types of lightning
Cloud to ground is the most common type of lightning seen in nature, but hardly the only type of lightning causing wind turbine damage. In the latest issue of PES magazine, Allen Hall, lightning expert and Weather Guard CEO, explains the various types of lightning and what wind turbine operators need to understand about IEC standards, which are good, but not comprehensive.
While Hall explains that lightning itself isn’t that complex (“it’s …super-heated air”) the array of diagnostic and protective measures that can feel, at times, overwhelming. But those tools have provided data that show lightning damage has been underestimated and explained away with overly-simple responses like “force majeure.” As turbines get taller, lightning damage becomes more prevalent. This article offers practical approaches to identifying and more importantly, minimizing lightning damage.
Click here to read the full article (no subscription required).
