# Power Quality Impact and Its Assessment: A Review and a Survey of Lithuanian Industrial Companies
## 2 Literature Review
### Environmental Impact
Most studies focus only on the calculation of victims in a certain period of time: for instance, according to the results of [44], in 2011, 161 birds were found beneath the power lines under investigation in the Indian state of Rajasthan between 31 November and 6 December, including 59 house rows (_Corcus splendens_), 47 Indian rollers (_Coracias benghalensis_) and 18 Eurasian collared doves (_Streptopelia decaocto_), and according to the results of [45], in September 2007, more than 70 bird carcasses were found under the inspected power grid section in the Mongolian steppe (data are segregated into birds found under the poles by their type and birds found under the lines), including common kestrels (_Falco timnuculus_), golden eagles (_Aquila chrysaetos_), little owls (_Athene notuca_), [PERSON]'s sandgrouses (_Syrrhaptes paradoxus_), saker falcons (_Falco cherrug_), steppe eagles (_Aquila nipalensis_), and upland buzzards (_Buteo hemilasius_). Nonetheless, several examples can be found when the number of birds found under power lines is divided into collisions and electrovutions. For instance, during the study presented in [46], a total of 4353 victims was found beneath the power lines under investigation in Slovakia between December 2014 and February 2016: the largest number of victims were common buzzards (_Buteo butoe_)--1028 (3 by collision, 1025 by electrocution), followed by 606 (5 by collision, 601 by electrocution) common magpies (_Pica pica_), 218 (6 by collision, 212 by electrocution) hooded crows (_Corcus cornix_), 189 (all by collision) mute swans (_Cygnus olor_), etc. During the study presented in [47], a total of 43 victims was found beneath the power lines under investigation in the Patalibazar Municipality of the Syangia district of Nepal from November 2021 to May 2022, including 13 (2 by collision, 11 by electrocution) house crows (_Corcus splendens_), 7 (6 by collision, 1 by electrocution) Indian mynas (_Acridotheres tristis_), and 6 (1 by collision, 5 by electrocution) rock doves (_Columbia livia_). However, it should be noted that in these studies, the cause of death was decided by examining the carcass of the killed birds, and not by analyzing PQ measurement data. According to [48] (p. 14), bird electrocution is a worldwide problem identified especially on the MV power lines (1-52 kV) and railway infrastructure--it is probably reasonable to believe that a transmission grid is safer than a distribution grid in terms of bird electrocutions due to the greater distances between the wires. Examples of animal interactions with electricity grid depend on geographic location and include not only birds: for instance, the collisions of a bald eagle (_Haliaetus leuccephalus_) with power lines in the United States are described in [49; 50], a leopard (_Panthera pardus_) that was electrocuted after climbing up an electric pole in India in [51], the electrocution of an Asian elephant (_Elephas maximus_) by a sagging power line in [52], by a fallen power line (which purportedly was pushed by the animal) in [53], and the electrocution of an Indian python (_Python molurus_) by a 11 kV line (resulting in the supply interruption for more than 600 houses) in [54]. Electrocution can be the main factor of population decline (e.g., see [55], which studies the endangered populations of [PERSON]'s eagle (_Aquila fascita_) in Southern Europe, particularly in the Iberian Peninsula); however, the overall effect of electrocution on population dynamics is still unknown for most species [10; 48]. As can be seen from the statistical data of the Lithuanian 10 kV grid provided by [2], in 2015-2018, fauna caused 980 faults in the overhead power lines, 852 faults in the outdoor and modular substations (approximately 30% by birds, approximately 50% by rodents), and 336 faults in the pole mounted substations (approximately 80% by birds).