Wind Turbine

Wind turbines are natural lightning rods due to the height of the structure and their placement in large, flat open areas on land and also in the open ocean. On average, they are subject to about 10 lightning strikes per year – but this largely depends on geographical location.

Wind turbines are affected by both downward and upward lightning. Downward-initiated lightning is generated from a thunderstorm or cloud formation that usually impacts the tip or leading edge of the turbine blade first, then makes its way to the generator, and finally grounds itself through the structure. Upward lightning is generated by the wind turbine itself. When the height of the wind turbine exceeds 325 feet at the nacelle, the tip height can extend more than 200 feet beyond the center. As the turbine spins at greater speeds, atmospheric conditions make it possible for the turbine’s own electrical field to actually generate lightning from the turbine blades themselves – arcing upward to meet a downward bolt.

These lightning strikes can cause extensive damage and potentially completely destroy the wind turbine. The immediate delivery of high voltage and amperage across the system can make blades break off, generators explode, and electrical systems damaged beyond repair. This damage causes extensive downtime and can be very costly to repair. How can we protect these renewable energy sources from lightning strikes and comply with IEC 61400-24 Lightning Protection?

Wind turbine blades need to be long to generate as much energy as possible when there is wind available. This extended length means that they are designed to be very light, but also need to be strong enough to withstand the forces exerted on them at maximum speeds. This design requirement makes carbon fiber-based materials a perfect solution for the required strength-to-weight ratio. Unfortunately, composite materials like this are not good at distributing the energy from lightning strikes on wind turbines. PEMPL Mesh expanded metal foil is easily incorporated into the carbon fiber and composite material design of the turbine blades, nacelle, and rotor hub generator shell to provide lightning a path through the wind turbine without damaging critical components and systems. PEMPL Mesh is designed to protect wind turbine components in the Lightning Protection Zones LPZ 0A, LPZ 0B, and LPZ 1.

The PEMPL Mesh expanded metal foils are available in copper and aluminum in addition to various other metal types. The proprietary PEMPL Metals expanding process is lubricant-free and runs faster than the competition. This means your wind turbine lightning protection material can be manufactured faster than any other expanded material, won’t come apart like woven wire cloth, and is ready to install without additional cleaning or surface preparation. This helps save your project money and protects the sensitive equipment delivering energy to people depending on the production.

PEMPL Mesh expanded metal foils are available in standard sizes with diamond patterns from 0.030”- 0.500”. The configurations offer a wide range of openings per square inch – from 25 to 5,000. Custom expanded metal foil designs, patterns, openings, materials, thicknesses, widths, and forming’s are available.

The micro expansion mesh is widely used in the wind turbine blade manufacturing, it can also be installed on the aircraft, turbine cabin cover of wind power plants, as well as on high-altitude electrical appliances and machines to prevent lightning attacks, but also can provide a certain shielding effect.