Regional and seasonal analysis of publicly available data for VoLL estimation when missing dedicated survey

For cost efficient and timely network expansion investments, development planning must transparently and impartially compare classic infrastructural network investment costs and customer flexibility service operating expenditures. Cost-benefit analysis (CBA) is a suitable tool, but results are strongly dependent on accuracy of input parameters. One of the most important parameters is the value of lost load (VoLL), usually determined by a regulatory defined methodology, reflecting often conflicting aspects of reliability of electricity supply, including customer willingness to pay, DSO's network planning criteria and regulatory tariff methodology. The proposed approach evaluates regional and seasonal variations using publicly available data, thereby addressing the absence of dedicated surveys and improving cost-efficiency in planning processes. The analysis was performed as part of the study initiated by the HEP Distribution System Operator Ltd. to improve network expansion planning and applied the results and best practice recommendations of studies and methodologies provided by the Agency for the Cooperation of Energy Regulators (ACER). Based on analyses performed, a transparent methodology for annual amendment of VoLL is proposed, which gives annual VoLL for Croatia over 1,6 times higher than according to currently used methodology.