Recognizing climate change in electricity network design and construction

The report presents how climate will change according to climate models concerning the planning and building of electric power networks from the present state to the period from 2016 to 2045. The essential impacts of changes in weather conditions on planning and building of electric network are defined regionally based on the climate change scenarios. The importance of the effects is shown as costs and failure durations for different line structures. Moreover, the influence of the climate change on the loading capacity of the power system components is presented. On the basis of all these factors it will be judged how strong an effect the climate change has in the present electric power network and how one should be prepared for it. The stresses of the network will increase with climate change. This will increase the number of faults in current network and at the same time the total duration of faults, if improvements for reliability will not be increased. The effect is most significant for a bare overhead line network passing through a forest in rural areas. However, it is profitable to consider the final impacts in detail, because the weather causes faults in different ways depending on environmental conditions. Principally, the impact of climate change is remarkable especially in the regions that are even nowadays sensitive to weather. Poor access to the fault locations increases the repairing time. A forest sensitive to weather conditions increases number of faults and thus the total interruption time. Based on the calculations the influence of climate change is much lower at the roadside and even lower in the fields. Urban networks are already mostly underground cable networks having considerably lower climate effects. Increasing costs due to the climate change increases also the profitability of the investments planned for improving the reliability of the network. The profitability and sufficiency of the investment aiming at reliable distribution always need a case-specific consideration. In regions sensitive to the crown snow loads it is useful to concentrate on trimming and clearing as well as to ensure the withstand strength of line and pole structures against snow loads. The predictions always include some uncertainty. In this work the uncertainty is assessed by the different climate change scenarios as well as by estimating how significant the calculated results are compared to the total costs. The report estimates the risk caused by the climate change.