The transfer capabilities of High-Voltage Overhead Lines (HV OHLs) are often limited by the critical power line temperature that depends on the magnitude of the transferred current and the ambient conditions, i.e., ambient temperature, wind, etc. To utilize existing power lines more effectively (with a view to progressive decarbonization) and more safely with respect to the critical power line temperatures, this paper proposes a Dynamic Thermal Rating (DTR) approach using IoT sensors installed on some HV OHLs located in different Italian geographical locations. The goal is to estimate the OHL conductor temperature and ampacity, using a data-driven thermo-mechanical model with the Bayesian probability approach, in order to improve the confidence interval of the results. This work highlights that it could be possible to estimate a space-time distribution of temperature for each OHL and an increase in the actual current threshold values for optimizing OHL ampacity. The proposed model is validated using the Monte Carlo method.

This work deals with a technical and economical comparison between hydrogen and liquid natural gas (LNG) fueled buses with reference to the standard solution based on diesel fuel internal combustion engines. The level of service is evaluated considering the number of buses replaced and the average kilometers traveled each year for two levels. The economical comparison is made using the Total Cost of Ownership (TCO) method considering capital and operating costs. The costs of LNG and Diesel (at the pump in Italian market) are estimated with reference to the year 2020. Furthermore, an assessment of greenhouse gas emissions will be carried out starting from energy needs, adopting a “cradle to grave” approach, thus evaluating emissions from the well to the tank and from the tank to the wheel. The results show that the operating costs (0.778 €/km) of LNG solution are lower than the Diesel ones (1.072 €/km), while the hydrogen buses can become competitive in the next few .The production of hydrogen with water electrolysis considering the current electricity costs of the Italian market is expensive and involves a cost to the hydrogen pump 7,60 €/kg which makes the operating cost of the hydrogen solution is equal to about 1.420 €/km which makes this solution uncompetitive. It is also important to underline that the cost of green hydrogen production from water electrolysis strongly depends on the cost of electricity. The Life Cicle Analisis (LCA) analysis shows strong environmental benefits of the hydrogen solution in terms of CO_2eq if the hydrogen is produced by electrolysis using renewable energy sources. In the other cases, the advantage of using hydrogen is not very strong as it is associated with the use of fossil fuels that release climate-altering substances.