Two different Lightning Protection technologies are coexisting: the “conventional” systems based on the Meshed Cage design (copper conductors grid around the whole structure) and the Early Streamer Emission air terminals that provide a protection over much larger areas and require only two down conductors per air terminal. These technologies are providing similar protection to the structure to reduce the risk of direct lightning discharge but their environmental impact is very different: while almost 300kg of copper conductors are required to install a Meshed Cage on a 40m x 20m x 10m building, ESE air terminal would require … 22kg only ! 95% of the overall amount of copper has been mined in the 20th century. Prices of copper are now reaching 9,000USD/ton at the LME market compared to less than 2,000 USD/ton ten years ago: Conventional Lightning Protection design is not environmentally and economically sustainable but this industry can participate into the widening effort to reduce the use of nonrenewable energy and materials: The sustainable development way is definitely heading towards an increasing use of ESE rods and the drastic limitation of Meshed Cage design.
For more detailed information, please log on www.intlpa.org “Unsustainable trends in lightning protection industry” by Pr. Jaouad ZEMMOURI – University of Science and Technology –Phlam Laboratory- Lille- France