TenneT conducted a pilot with drones to hang wire markers for birds on a 150 kV high-voltage line between Dodewaard and Ede in the Netherlands.
While Slovak drone company FiiHaa managed the project over a length of 2 km on the route near Wageningen for TenneT, contractor Qirion supervised the work.
A drone is environmentally friendly and cost-efficient as it does not require heavy machinery like helicopters or cranes and climbers to install wire markings.
A different type of wire marking technique is used in case of drones instead of pig curls or bird flaps. Firefly can be attached with a clamp to the lightning conductors in the high-voltage line.
According to studies, the effectiveness of Fireflies is similar as compared to pig curls and bird flaps and leads to about 90% fewer wire casualties.
To limit damage at the population level of birds, TenneT highlights areas by comparing the location of the high-voltage grid with the distribution of bird flight movements. Connections are made more visible to birds by hanging plastic or metal markings on the lightning wire.
"Commissioned by TenneT, Sovon Vogelonderzoek Nederland (SOVON) investigated where in the Netherlands the risk of wire casualties is highest,” said TenneT ecologist, Jac Hakkens. “This connection near Wageningen was on our list as a priority and we are evaluating this new method with the drones.”
Wire marker mounting is expensive on existing connections than during the construction of new high-voltage connections, or major maintenance.
Fixing wire markers can also be very expensive if they cannot be installed from the ground. Therefore, helicopters are used to attach the markings, which is expensive and causes more disruption to the surrounding area as compared to the drones.