EVN Bulgaria (Elyug) implemented bird-friendly power lines involving the insulation of components of the grid infrastructure and the installation of additional elements to overhead power lines in order to protect both the lines and specific bird species. The practice is part of the Life for Safe Grid project (life 12 NAT/BG/000572) funded by the Life Programme of the EU.
The insulation of power lines is a common practice for bird protection. However, PAS system is innovative as it combines various protective measures in one holistic system in an efficient and bird-friendly way. It is composed of the following elements: wire, insulation coating on the line (weatherproof synthetic VPE material), insulated parts (fittings, connectors to the pole, consoles) and protective elements, such as perches, that provide a higher and safer place for birds to rest, and wing space diverters, that ensure a gap between the pole and the place available for birds to perch.
The practice was first implemented along a 15 km stretch of the overhead power line “Balgarin”. The line passes across the Sakar Special Protected Area (SPA), which is part of the Natura 2000 network and the most important SPA for the Imperial Eagle in Bulgaria, holding 10 breeding pairs and supporting the young birds during their dispersion period. The Imperial Eagle is classed as one of numerous vulnerable species according to the Red list of Threatened Species. Unnatural mortality caused by aboveground electric infrastructure has been proven to be the major threat for juvenile and immature Imperial Eagles in Bulgaria. In the period 2009–2012, over 78% of all juvenile eagles have died as a result of electrocution. PAS evaluation of the effect on bird mortality will be undertaken in 2018, but the first results indicate reduced disturbances on the grid since the implementation of the line, which is a great indicator of success regarding the protection of both the birds and the line.