This paper deals with the occurrence of hot spot phenomena in photovoltaic (PV) systems under partial shading caused by objects on some parts of the modules. An interesting case of diffuse shadows is determined by Overhead distribution Lines whose path crosses or are in the proximity of the PV Power plants. Investigating the impact of these shadows on reducing the Power production of PV or on damaging the PV modules as the modules’ temperature is increasing, is of high interest. At the Solar Tech laboratory of Politecnico di Milano, the conditions for hot spot phenomena occurrence due to the Overhead Lines shading the PV cells were reproduced. Two experimental campaigns were carried out to investigate the current– voltage and Power–voltage characteristics, and the energy production. In each experimental campaign, the built shading structure was considered fixed and different shading conditions were created based on the natural displacement of the sun. The hot spot phenomena was revealed on a field PV installation in Italy, caused my medium voltage Overhead Lines shading the PV cells, using infrared imagery.

Background: Living in the vicinity of high voltage Power Lines has brought about a range of health woes, but the effect of residential exposure to electromagnetic fields from the Power Lines on female fertility has not been explored yet. Objective: To test the hypothesis if residential proximity to high voltage Power Lines could be associated with the increased risk of female infertility. Methods: In a case-control study, 462 women with confirmed diagnosis of unexplained infertility or behavioral and environmental factors were assessed between February 2014 and December 2016. Control group comprised of 471 persons with no history of infertility selected using randomized-digit dialing from the numbers registered in a birth registry between 2014 and 2016. The nearest linear distance from high voltage Power Lines to the participants' residence of cases and controls was measured using a Geographical Information System (GIS) and Google Earth aerial evaluation for high voltage Power Lines (240– 400 kV). Results: 112 (14. 1%) houses were within 500 meters from a high voltage Power line. Women living within 500 meters of the Lines (OR 4. 14, 95% CI 2. 61 to 6. 57) and 500– 1000 meters of the line (OR 1. 61, 95% CI 1. 05 to 2. 47) carried a significantly higher risk of infertility than those women living more than 1000 meters away from the Power Lines. After adjusting for confounding factors, women living within 500 meters of the Lines carried a higher risk (aOR 4. 44, 95% CI 2. 77 to 7. 11) of infertility compared with women living more than 1000 meters of the Lines. Conclusion: The current safety guideLines for electromagnetic fields exposure seems to be not adequate for protecting people from the hazardous effects of the field.

A new type of closed-type lightning protection multi-chamber arrester named impulse quenching line lightning protection device (LLPD) used for protection of Overhead Power Lines is described. After the passing of lightning current, the multi-chamber system of the arrester prevents the occurrence of a network short-circuit current due to the total voltage drop across several thousand series-connected spark gaps that significantly exceeds the applied network voltage in magnitude. The total operating time of the LLPD is less than 1 ms which is not sensitive for microprocessor and relay protection of Overhead Lines. A computational estimation of the emergency outage rate of double-circuit Overhead Power Lines without an Overhead ground wire resulting from lightning overvoltage was carried out. Number of current impulses used when arresters are tested for quenching capacity as well as their parameters were determined by the mathematical modeling using the statistical Monte Carlo method. Results of calculation that make it possible to determine the efficiency of lightning protection of double-circuit Overhead Lines with various placement schemes of the line lightning protection device LLPD-110 of the company Streamer Electric AG are presented in the conclusion.

Routing of high-voltage electric transmission Lines for the connection of renewable energy-distributed generation plants is a critical issue from an environmental point of view. A standard methodology that accounts for multiple perspectives, influence factors and is able to mediate between weighted constraints can be a useful tool for the regulating bodies that are involved in approval processes. The methodology can be an effective support to increase reliability, save consumers’ money and mitigate the unavoidable impacts of the Lines on the population living nearby. In this paper we investigate the suitability of a procedure employed by Terna, the Italian high-voltage transmission system operator, to identify the corridors where to route new Overhead transmission Lines with the lowest environmental impact. The methodology is based on the subdivision of all the relevant constraints dictated by environmental issues and territory legislations in four main classes. A real case study concerning the design and connection of a wind farm placed near Collarmele, in the center of Italy, shows the effectiveness of the proposed methodology.