TY - RPRT A1 - Fusar Bassini, Chiara A1 - Xu, Alice Lixuan A1 - Sánchez Canales, Jorge A1 - Hirth, Lion A1 - Kaack, Lynn H. T1 - Flexibility of German gas-fired generation: evidence from clustering empirical operation N2 - A key input to energy models are assumptions about the flexibility of power generation units, i.e., how quickly and often they can start up. These assumptions are usually calibrated on the technical characteristics of the units, such as installed capacity or technology type. However, even if power generation units technically can dispatch flexibly, service obligations and market incentives may constrain their operation. Here, we cluster over 60% of German national gas generation (generation units of 100 MWp or above) based on their empirical flexibility. We process the hourly dispatch of sample units between 2019 and 2023 using a novel deep learning approach, that transforms time series into easy-to-cluster representations. We identify two clusters of peaker units and two clusters of non-peaker units, whose different empirical flexibility is quantified by cluster-level ramp rates. Non-peaker units, around half of the sample, are empirically less flexible than peakers, and make up for more than 83% of sample must-run generation. Regulatory changes addressing the low market responsiveness of non-peakers are needed to unlock their flexibility. Y1 - 2025 U6 - https://doi.org/10.48550/arXiv.2504.16943 PB - arXiv ER - TY - RPRT A1 - Sánchez Canales, Jorge A1 - Xu, Alice Lixuan A1 - Fusar Bassini, Chiara A1 - Kaack, Lynn H. A1 - Hirth, Lion T1 - An empirical estimate of the electricity supply curve from market outcomes N2 - Researchers and electricity sector practitioners frequently require the supply curve of electricity markets and the price elasticity of supply for purposes such as price forecasting, policy analyses or market power assessment. It is common practice to construct supply curves from engineering data such as installed capacity and fuel prices. In this study, we propose a data-driven methodology to estimate the supply curve of electricity market empirically, i.e. from observed prices and quantities without further modeling assumptions. Due to the massive swings in fuel prices during the European energy crisis, a central task is detecting periods of stable supply curves. To this end, we implement two alternative clustering methods, one based on the fundamental drivers of electricity supply and the other directly on observed market outcomes. We apply our methods to the German electricity market between 2019 and 2024. We find that both approaches identify almost identical regimes shifts, supporting the idea of stable supply regimes stemming from stable drivers. Supply conditions are often stable for extended periods, but evolved rapidly during the energy crisis, triggering a rapid succession of regimes. Fuel prices were the dominant drivers of regime shifts, while conventional plant availability and the nuclear phase-out play a comparatively minor role. Our approach produces empirical supply curves suitable for causal inference and counterfactual analysis of market outcomes. Y1 - 2025 U6 - https://doi.org/10.48550/arXiv.2511.23068 PB - arXiv ER - TY - RPRT A1 - Stiewe, Clemens A1 - Xu, Alice Lixuan A1 - Eicke, Anselm A1 - Hirth, Lion T1 - Cross-border cannibalization: Spillover effects of wind and solar energy on interconnected European electricity markets N2 - The average revenue, or market value, of wind and solar energy tends to fall with increasing market shares, as is now evident across European electricity markets. At the same time, these markets have become more interconnected. In this paper, we empirically study the multiple cross-border effects on the value of renewable energy: on one hand, interconnection is a flexibility resource that allows to export energy when it is locally abundant, benefitting renewables. On the other hand, wind and solar radiation are correlated across space, so neighboring supply adds to the local one to depress domestic prices. We estimate both effects, using spatial panel regression on electricity market data from 2015 to 2023 from 30 European bidding zones. We find that domestic wind and solar value is not only depressed by domestic, but also by neighboring renewables expansion. The better interconnected a market is, the smaller the effect of domestic but the larger the effect of neighboring renewables. While wind value is stabilized by interconnection, solar value is not. If wind market share increases both at home and in neighboring markets by one percentage point, the value factor of wind energy is reduced by just above 1 percentage points. For solar, this number is almost 4 percentage points. Y1 - 2024 U6 - https://doi.org/10.48550/arXiv.2405.17166 PB - arXiv ER - TY - JOUR A1 - Stiewe, Clemens A1 - Xu, Alice Lixuan A1 - Eicke, Anselm A1 - Hirth, Lion T1 - Cross-border cannibalization: Spillover effects of wind and solar energy on interconnected European electricity markets JF - Energy Economics N2 - The average per-MWh revenue, or market value, of wind and solar energy tends to fall with increasing market share, as is now evident across European electricity markets. At the same time, these markets are becoming more interconnected. In this paper, we empirically study cross-border effects on the value of renewable energy: On one hand, interconnection is a flexibility resource that allows to export energy when it is locally abundant, benefitting renewables. On the other hand, wind and solar patterns are correlated between countries, so neighboring supply adds to the local one to depress domestic prices. We estimate both effects, using spatial panel regression on electricity market data from 2015 to 2023 from 30 European bidding zones. We find that domestic wind and solar value is not only depressed by domestic, but also by neighboring renewables expansion. The better interconnected a market is, the smaller the effect of domestic but the larger the effect of neighboring renewables. While wind value is stabilized by interconnection, the data suggest that solar value is not. These results can be used to estimate the impact of simultaneous domestic and neighboring capacity expansion: If wind market share increases both at home and in neighboring markets by one percentage point, the value factor of wind energy is reduced by just above 1 percentage point. For solar, this number is almost 4 percentage points. Y1 - 2025 U6 - https://doi.org/10.1016/j.eneco.2025.108251 SN - 0140-9883 N1 - Open Access publication is funded by the Hertie School Library VL - 143 PB - Elsevier BV ER -