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Electrical power systems represent an immense source of electromagnetic radiation spanning a wide frequency range, encompassing low-frequency, transient states, and high-frequency emissions. The radiation poses a significant self-pollution challenge for electric and electronic devices situated in close proximity to these systems. The present article aims to address this research, and provides a comprehensive review of the electromagnetic effects and pollution at differences frequency's ranges encompassing power systems network. In the context of the low-frequency range, the computation of electric and magnetic fields is conducted using quasi-static principles. To validate the behavior at high frequencies due to power line currents, Schelkunoff's approach is employed. Additionally, transient electromagnetic fields are analyzed using an exact analytical method. The results of computer simulations are compared with previously published and measured data for low-frequency regime and transient overvoltage conditions, verifying their consistency. Additionally, high-frequency results are presented and corroborated through the utilization of a numerical electromagnetic code (NEC-4). These analyses underscore the valuable role of computer-based calculations in examining the electromagnetic environment of power system networks. [ABSTRACT FROM AUTHOR]

The inspection of power transmission and distribution systems is performed visually by foot patrolling and helicopter methods. These methods have various disadvantages such as time-consuming, high operating cost, safety issues, and improper results. To overcome this issue, power utility companies are searching for the alternatives like Unmanned Aerial Systems (UAS) or drones. UAS are safe, cost effective, and requires less time for power transmission line inspection compared to the regular methods. In this manuscript, a decisive flight path planning for UAS to visually inspect a power transmission line and towers is explained. The objective of this paper is to maximize the performance of three functions such as coverage of transmission tower, quality of captured image, and flight time. Second, proposing an automated inspection strategy for UAS to follow the overhead power transmission lines. These objectives are achieved by formulating a cost function, to convert the path planning into a safe operation for UAS. The results of Particle Swarm Optimization (PSO) and Simulated Annealing (SA) are compared to find the best path for UAS. The experimental finding shows that PSO algorithm has higher efficiency and effectiveness compared to the SA algorithm and benefits the UAS with a safe flight path for the inspection of power transmission towers. [ABSTRACT FROM AUTHOR]

This study draws on environmental and energy justice research to develop the analysis of energy infrastructure opposition from a justice perspective. A comprehensive data set of 70 cases of opposition to socioenvironmental effects of proposed electricity power lines in North America was developed. The analysis of strategic frames used by opposition groups provides the basis for an evaluation of theoretical categories of justice, their empirical operationalization, and their limits. Four categories of justice are associated with eight of the 12 main types of frames. In turn, frames are connected to types of opposition actors in the analysis of sequences of justice-related actions and outcomes. Subnational governments are important actors in many cases that have outcomes of remediation and/or a decision not to build the line. Coalition breadth and opposition from federal government actors, marginalized groups, and environmentalists are also associated with those outcomes. [ABSTRACT FROM AUTHOR]

Electrocution on poorly designed power pylons is one the most important human-related causes of large bird mortality worldwide. Raptor mortality caused by 22 kV distribution power lines was studied in south-west Morocco. We surveyed 323 pylons (53.5 km) and collected 65 carcasses of electrocuted raptors in the period 2016 to 2019. The species most affected by electrocution were Long-legged Buzzard and Bonelli's Eagle (49.23% and 29.23%, respectively). Average electrocution rate was 0.201 carcasses pylon−1. Metal pylons, suspended insulators, devices and vaulted configuration had the highest electrocution events. Substitution or corrective measures should be applied on existing pylons that pose the greatest risk to resident breeding and threatened wintering raptors, such as Bonelli's Eagle and Spanish Imperial Eagle in this area. [ABSTRACT FROM AUTHOR]

Research has shown how the NIMBY explanation for local opposition to energy infrastructures has made its way into the discourses of developers, policy makers, the media and active protesters. However, few studies have explored how community members draw on discourses of NIMBYism to interpret and negotiate responses to local energy proposals. We address this gap drawing on qualitative data from two UK case studies. Analyses show that NIMBY, as a representation of objection, is both widespread and polysemic. Aside from providing a means to talk about space, NIMBY is sometimes rejected by discourses positioning publics as custodians of valued landscapes. In other instances, it is assumed to be a normative and legitimate way for participants to decide what is best for them in a neo-liberal society. The findings reinforce the importance of examining socio-cultural dimensions of social acceptance, specifically representations of community responses to infrastructures as political devices in local siting disputes, and publics as reflexive actors. [ABSTRACT FROM AUTHOR]

The automatic classification of power lines from airborne light detection and ranging (LiDAR) data is a crucial task for power supply management. The methods for power line classification can be either supervised or unsupervised. Supervised methods might achieve high accuracy for small areas, but it is time consuming to collect training data over areas of different conditions and complexity. Therefore, unsupervised methods that can automatically work over different areas without sophisticated parameter tuning are in great demand. In this paper, we presented a hierarchical unsupervised LiDAR-based power line classification method that first screened the power line candidate points (including the power line corridor direction detection based on a layered Hough transform, connectivity analysis, and Douglas–Peucker simplification algorithm), followed by the extraction of contextual linear and angular features for each candidate laser points, and finally by setting the feature threshold values to identify the power line points. We tested the method over both forest and urban areas and found that the precision, recall and quality rates were up to 96.7%, 88.8% and 78.3%, respectively, for the test datasets and were higher than the ones from a previously developed supervised classification method. Overall, our approach has the advantages of achieving relatively high accuracy and being relatively fast. [ABSTRACT FROM AUTHOR]

Thunderstorm asthma and increased childhood leukemia risk near high-voltage power lines (HVPL) are occurrences whose mechanism of effect is not fully understood. This paper proposes and discusses a key similarity: both thunderstorms and HVPL generate a high enough electrical field in the environment to ionize nearby air and air-borne particles. I argue that the repeatedly demonstrated acute asthma response to pollen-laden air during thunderstorms is largely due to ionization of air-borne allergens, which adhere more readily and in greater quantity in the lungs than non-ionized particles. If these bind to mucous or phagocytic cells, it would enhance immune response. A rapid temperature drop and high ozone also seem to be drivers of thunderstorm asthma. This causal nexus provides strong support for the parallel situation of prolonged exposure to ionized particles near HVPL and an increased rate of childhood leukemia. Here, it is proposed that upwind carcinogens are ionized when passing HVPL and then residential and business areas. Published evidence for most steps are presented, but have not previously been published as a coherent whole, nor has it been suggested that the inhaled ionized micro-particle explanation for acute asthma may also explain development of childhood leukemia over time. The demonstrated series of events leading to increased deposition and retention of ionized particles in airways provides support for explaining both adverse health outcomes: acute thunderstorm asthma and increased risk of childhood leukemia near HVPL. Further support for this explanation of both outcomes is provided by effects of on-going proximity to highways. [ABSTRACT FROM AUTHOR]

The results of a 2 × 2 factorial online experiment are reported. The first factor refers to the information on precautionary measures and the second factor on the information regarding the share of EMF exposure from extra-high-voltage power lines compared to overall EMF exposure measured in-house. The study is based on a community sample of 440 subjects. Information on the share of EMF exposure from extra-high-voltage power lines at the in-house overall EMF exposure has no statistically significant effect of safety distances and acceptance distances. Further findings indicate that communications of precautionary measures produce a countervailing effect: on average, subjects require a higher distance from their homes compared to those who were not informed about precautionary measures. However, there is also a positive effect of precautionary information on the acceptance belief. Subjects who received this information are, in average, less negative about the claim that compliance with the value limit is sufficient in order to agree with the construction of a power line. Possible explanations of the findings such as cognitive dissonance, negativity bias, and style of information processing are discussed. [ABSTRACT FROM AUTHOR]

The aetiology of amyotrophic lateral sclerosis (ALS), a rare and extremely severe neurodegenerative disease, has been associated with magnetic fields exposure. However, evidence for such a relation in the general population is weak, although the previous null results might also be due to exposure misclassification, or a relationship might exist only for selected subgroups. To test such a hypothesis we carried out a population-based case-control study in two Northern and Southern Italy regions, including 703 ALS cases newly diagnosed from 1998 to 2011 and 2737 controls randomly selected from the residents in the study provinces. Overall, we found that a residence near high-voltage power lines, within the corridors yielding a magnetic fields of ≥0.1 μT, was not associated with an excess disease risk, nor did we identify a dose-response relationship after splitting the exposed corridor according to the 0.1, 0.2 and 0.4 μT cut-points of exposure. These results were confirmed taking into account age at onset, period of diagnosis, sex, geographical area, and length of exposure. Overall, despite the residual possibility of unmeasured confounding or small susceptible subgroups not identified in our study, these results appear to confirm that the exposure to magnetic fields from power lines occurring in the general population is not associated with increased ALS risk. [ABSTRACT FROM AUTHOR]

In this article, I reflect on relationship and movement building across power lines that I have experienced or witnessed in and outside of academia. I argue that the "anesthetic aesthetic" of whiteness, as illuminated by Mab Segrest, compels those like myself who are trained to be white to distance ourselves from the pain and suffering of others (as well as our own) in order to accept and assimilate into the hegemonic normative systems of power. I offer stories from my experience of feminist and queer organizing that demonstrate how this distancing looks and feels, and places of where it might be transformed. Then, I turn to healing justice as a praxis that creates communal spaces for naming, recognizing, and healing from violence, spaces to share our brokenheartedness, and to serve as a way of breaking up the gravitational pulls of white supremacist patriarchy. [ABSTRACT FROM AUTHOR]

Cables and overhead lines are key components in electric power systems, with conductors belonging to those components being electromagnetically coupled. Time-domain analysis of steady-state and transient regimes in cables and power lines usually requires the use of frequency-domain modal analysis techniques where mode decoupling is achieved by solving an eigenvalue–eigenvector matrix problem. In this article, an alternative method is developed for the modal analysis ofn-coupled multi-conductor transmission lines employing a simple intuitive approach. The method provides a speedy solution of the eigenvalue–eigenvector problem based on an initial guess for the modal transformation matrix; the accuracy of the method can be controlled and improved easily by iterating the proposed algorithm a few times. The method is exemplified with vertical and triangular single-circuit three-phase transmission lines choosing the Clarke matrix as the initial approximation for the modal transformation. [ABSTRACT FROM AUTHOR]

Cases of strong local opposition to the planned introduction of new high-voltage power lines (HVPLs) have been documented in the past. During and after the planning process for a new HVPL, local residents will be informed about the siting process and its outcomes. Although it has been suggested in the literature that this communication plays an important role in residents' responses to a new HVPL, it has been rarely empirically studied. In this qualitative study, we conducted in-depth interviews with 15 residents about their experiences with the planned introduction of a new HVPL near their homes. Thematic analysis revealed that residents' experiences were centred around negative expectations of living near the new HVPL and perceived injustice of the planning process and its outcomes. Residents' perception that communication was not tailored to their information needs played a significant role in these negative experiences. Suggestions for improving communication will be discussed. [ABSTRACT FROM AUTHOR]

Natural and semi-natural habitats are declining. However, little is known of the value of artificial and human-altered habitats for biodiversity maintenance in fragmented landscapes. We hypothesized that railway tracks can have great value for butterflies as an alternative habitat. Using 200-m-long transects, we investigated species richness and two main types of β-diversity, i.e. nestedness and community dispersion, for both butterflies and their nectar plants in eight sites under an expected gradient of habitat quality – meadows, railway tracks, forest clearings and degraded meadows. Railway tracks and meadows had higher butterfly species richness than forest clearings and degraded meadow. Butterfly species distribution among sites was strongly related to the gradient of habitat quality that was measured as nectar plant composition. Railway tracks contained the widest pool of butterflies with species of various biotopes as well as a wide pool of nectar plants at a nested subset pattern of β-diversity. However, the pattern of community dispersion was opposite to what had been expected. Meadows and railway tracks, being more heterogeneous sites in terms of composition of nectar plants, supported slightly more homogeneous butterfly communities. This suggests that habitats of low quality, i.e. forest clearings and degraded meadows, have less-stable butterfly communities. We concluded that railway tracks located on sun-warmed embankments containing a reach pool of nectar plants could enable multi-species communities to persist in an environment of good suitability. Conservation managers should therefore focus on enhancing the quality of railway tracks and their vicinity through the preservation of a high abundance of various flowering plants. [ABSTRACT FROM AUTHOR]

Bird collision mortality associated with power lines is a global conservation challenge, but periodic carcass counts along power lines underestimate actual mortality because of survey biases. We conducted a scavenger trial over 90 days and three observer detection trials after 1, 48 and 90 days using 44 wild goose carcasses to identify explanatory variables and estimate correction factors for these biases. Scavenging activity was high but mostly occurredin situ; only 16% (95% binomial CI 5–27%) of carcasses were removed by the end of the 90-day trial period (all within the first three weeks). Observer experience did not significantly affect detection rate, with experienced observers locating 75% (95% CI 68–83%) of carcasses compared with 67% (95% CI 58–75%) by naïve observers. Vegetation height, distance from the line and carcass spread were significant explanatory variables. The pattern in detection rate linked to carcass age was variable; there were fewer detections after 48 days, but rates at day 1 and day 90 were similar for experienced observers because bleached bones were highly visible. This suggests that long survey intervals are acceptable for the detection of large bird carcasses in arid environments such as the Karoo where collisions are infrequent but widespread events. [ABSTRACT FROM AUTHOR]

Guidelines of exposure to power line magnetic fields are usually designed on a deterministic basis, making their validity and adequacy somewhat questionable. Based on an overall probabilistic approach, a method for risk assessment of exposure to overhead power line magnetic fields is presented. There are advantages to the probabilistic approach over conventional methods of developing the risk of exposure to overhead power line magnetic fields. In this article, a model is constructed to predict the randomness in power line magnetic fields, taking into account—in addition to line loading—the random nature of the parameters contributing to the temperature of the power line conductors, which in turn, influences the resulting conductor sag. Those parameters include line loading, ambient temperature, solar irradiation, and wind speed. The correlative nature of those parameters is also considered. The model accounts for the likelihood of the effects of those various operational and weather parameters (or variables), thus avoiding inflated risk estimates produced by compounding single-point worst-case values of the input variables and, consequently, leads to an improved risk assessment. [ABSTRACT FROM AUTHOR]

Overhead power transmission lines cause external costs including aesthetic impacts on the landscape. We use the contingent valuation method to estimate the external costs from these aesthetic impacts, and find that the social benefits of avoiding these negative impacts on the landscape exceed the costs of burying the lines as underground cables. Our best-estimate of the aesthetic benefits from burying the power lines was three times as large as the cost. These conclusions were based only on an assessment of the aesthetic impacts. Impacts of overhead power lines on wildlife and human health would likely make burial of power lines even more attractive. These results were obtained in an urban setting. Additional studies are needed to assess the costs associated with aesthetic impacts in rural and pristine natural areas, where power line construction is increasing. [ABSTRACT FROM AUTHOR]