Assessment of flexibility needs and options for a 100% renewable electricity system by 2030 in Austria

In June 2018, an ambitious target has been set in Austria for the domestic expansion of electricity generation from renewable energy sources (RES) by the Austrian Climate and Energy Strategy: The goal is to cover the total national electricity consumption, measured by yearly balance, with RES. With this goal, the country's power system is facing a significant transformation. Not only the necessary expansion rate of RES, but also safeguarding system stability, and preserving security of supply are major challenges that need to be tackled in the coming years. A high share of electricity generation from hydro, wind and PV is expected to lead to considerable, weather-related fluctuations in power supply. System flexibility is required to compensate short-to long-term (seasonal) differences between generation and consumption. This paper aims for assessing short-to long-term flexibility needs of the Austrian electricity system by 2030, which is intended to rely, almost exclusively, on RES and the use of flexibility options for meeting those needs. For this purpose, a high-resolution power and district heating model is used for the calculation of two distinct scenarios. Flexibility needs and coverage are quantified for these scenarios for different timescales, namely: daily, weekly, monthly and annually.